Solution to Sybil attacks and 51% attacks in Decentralized

Why i’m bullish on Zilliqa (long read)

Edit: TL;DR added in the comments
 
Hey all, I've been researching coins since 2017 and have gone through 100s of them in the last 3 years. I got introduced to blockchain via Bitcoin of course, analyzed Ethereum thereafter and from that moment I have a keen interest in smart contact platforms. I’m passionate about Ethereum but I find Zilliqa to have a better risk-reward ratio. Especially because Zilliqa has found an elegant balance between being secure, decentralized and scalable in my opinion.
 
Below I post my analysis of why from all the coins I went through I’m most bullish on Zilliqa (yes I went through Tezos, EOS, NEO, VeChain, Harmony, Algorand, Cardano etc.). Note that this is not investment advice and although it's a thorough analysis there is obviously some bias involved. Looking forward to what you all think!
 
Fun fact: the name Zilliqa is a play on ‘silica’ silicon dioxide which means “Silicon for the high-throughput consensus computer.”
 
This post is divided into (i) Technology, (ii) Business & Partnerships, and (iii) Marketing & Community. I’ve tried to make the technology part readable for a broad audience. If you’ve ever tried understanding the inner workings of Bitcoin and Ethereum you should be able to grasp most parts. Otherwise, just skim through and once you are zoning out head to the next part.
 
Technology and some more:
 
Introduction
 
The technology is one of the main reasons why I’m so bullish on Zilliqa. First thing you see on their website is: “Zilliqa is a high-performance, high-security blockchain platform for enterprises and next-generation applications.” These are some bold statements.
 
Before we deep dive into the technology let’s take a step back in time first as they have quite the history. The initial research paper from which Zilliqa originated dates back to August 2016: Elastico: A Secure Sharding Protocol For Open Blockchains where Loi Luu (Kyber Network) is one of the co-authors. Other ideas that led to the development of what Zilliqa has become today are: Bitcoin-NG, collective signing CoSi, ByzCoin and Omniledger.
 
The technical white paper was made public in August 2017 and since then they have achieved everything stated in the white paper and also created their own open source intermediate level smart contract language called Scilla (functional programming language similar to OCaml) too.
 
Mainnet is live since the end of January 2019 with daily transaction rates growing continuously. About a week ago mainnet reached 5 million transactions, 500.000+ addresses in total along with 2400 nodes keeping the network decentralized and secure. Circulating supply is nearing 11 billion and currently only mining rewards are left. The maximum supply is 21 billion with annual inflation being 7.13% currently and will only decrease with time.
 
Zilliqa realized early on that the usage of public cryptocurrencies and smart contracts were increasing but decentralized, secure, and scalable alternatives were lacking in the crypto space. They proposed to apply sharding onto a public smart contract blockchain where the transaction rate increases almost linear with the increase in the amount of nodes. More nodes = higher transaction throughput and increased decentralization. Sharding comes in many forms and Zilliqa uses network-, transaction- and computational sharding. Network sharding opens up the possibility of using transaction- and computational sharding on top. Zilliqa does not use state sharding for now. We’ll come back to this later.
 
Before we continue dissecting how Zilliqa achieves such from a technological standpoint it’s good to keep in mind that a blockchain being decentralised and secure and scalable is still one of the main hurdles in allowing widespread usage of decentralised networks. In my opinion this needs to be solved first before blockchains can get to the point where they can create and add large scale value. So I invite you to read the next section to grasp the underlying fundamentals. Because after all these premises need to be true otherwise there isn’t a fundamental case to be bullish on Zilliqa, right?
 
Down the rabbit hole
 
How have they achieved this? Let’s define the basics first: key players on Zilliqa are the users and the miners. A user is anybody who uses the blockchain to transfer funds or run smart contracts. Miners are the (shard) nodes in the network who run the consensus protocol and get rewarded for their service in Zillings (ZIL). The mining network is divided into several smaller networks called shards, which is also referred to as ‘network sharding’. Miners subsequently are randomly assigned to a shard by another set of miners called DS (Directory Service) nodes. The regular shards process transactions and the outputs of these shards are eventually combined by the DS shard as they reach consensus on the final state. More on how these DS shards reach consensus (via pBFT) will be explained later on.
 
The Zilliqa network produces two types of blocks: DS blocks and Tx blocks. One DS Block consists of 100 Tx Blocks. And as previously mentioned there are two types of nodes concerned with reaching consensus: shard nodes and DS nodes. Becoming a shard node or DS node is being defined by the result of a PoW cycle (Ethash) at the beginning of the DS Block. All candidate mining nodes compete with each other and run the PoW (Proof-of-Work) cycle for 60 seconds and the submissions achieving the highest difficulty will be allowed on the network. And to put it in perspective: the average difficulty for one DS node is ~ 2 Th/s equaling 2.000.000 Mh/s or 55 thousand+ GeForce GTX 1070 / 8 GB GPUs at 35.4 Mh/s. Each DS Block 10 new DS nodes are allowed. And a shard node needs to provide around 8.53 GH/s currently (around 240 GTX 1070s). Dual mining ETH/ETC and ZIL is possible and can be done via mining software such as Phoenix and Claymore. There are pools and if you have large amounts of hashing power (Ethash) available you could mine solo.
 
The PoW cycle of 60 seconds is a peak performance and acts as an entry ticket to the network. The entry ticket is called a sybil resistance mechanism and makes it incredibly hard for adversaries to spawn lots of identities and manipulate the network with these identities. And after every 100 Tx Blocks which corresponds to roughly 1,5 hour this PoW process repeats. In between these 1,5 hour, no PoW needs to be done meaning Zilliqa’s energy consumption to keep the network secure is low. For more detailed information on how mining works click here.
Okay, hats off to you. You have made it this far. Before we go any deeper down the rabbit hole we first must understand why Zilliqa goes through all of the above technicalities and understand a bit more what a blockchain on a more fundamental level is. Because the core of Zilliqa’s consensus protocol relies on the usage of pBFT (practical Byzantine Fault Tolerance) we need to know more about state machines and their function. Navigate to Viewblock, a Zilliqa block explorer, and just come back to this article. We will use this site to navigate through a few concepts.
 
We have established that Zilliqa is a public and distributed blockchain. Meaning that everyone with an internet connection can send ZILs, trigger smart contracts, etc. and there is no central authority who fully controls the network. Zilliqa and other public and distributed blockchains (like Bitcoin and Ethereum) can also be defined as state machines.
 
Taking the liberty of paraphrasing examples and definitions given by Samuel Brooks’ medium article, he describes the definition of a blockchain (like Zilliqa) as: “A peer-to-peer, append-only datastore that uses consensus to synchronize cryptographically-secure data”.
 
Next, he states that: "blockchains are fundamentally systems for managing valid state transitions”. For some more context, I recommend reading the whole medium article to get a better grasp of the definitions and understanding of state machines. Nevertheless, let’s try to simplify and compile it into a single paragraph. Take traffic lights as an example: all its states (red, amber, and green) are predefined, all possible outcomes are known and it doesn’t matter if you encounter the traffic light today or tomorrow. It will still behave the same. Managing the states of a traffic light can be done by triggering a sensor on the road or pushing a button resulting in one traffic lights’ state going from green to red (via amber) and another light from red to green.
 
With public blockchains like Zilliqa, this isn’t so straightforward and simple. It started with block #1 almost 1,5 years ago and every 45 seconds or so a new block linked to the previous block is being added. Resulting in a chain of blocks with transactions in it that everyone can verify from block #1 to the current #647.000+ block. The state is ever changing and the states it can find itself in are infinite. And while the traffic light might work together in tandem with various other traffic lights, it’s rather insignificant comparing it to a public blockchain. Because Zilliqa consists of 2400 nodes who need to work together to achieve consensus on what the latest valid state is while some of these nodes may have latency or broadcast issues, drop offline or are deliberately trying to attack the network, etc.
 
Now go back to the Viewblock page take a look at the amount of transaction, addresses, block and DS height and then hit refresh. Obviously as expected you see new incremented values on one or all parameters. And how did the Zilliqa blockchain manage to transition from a previous valid state to the latest valid state? By using pBFT to reach consensus on the latest valid state.
 
After having obtained the entry ticket, miners execute pBFT to reach consensus on the ever-changing state of the blockchain. pBFT requires a series of network communication between nodes, and as such there is no GPU involved (but CPU). Resulting in the total energy consumed to keep the blockchain secure, decentralized and scalable being low.
 
pBFT stands for practical Byzantine Fault Tolerance and is an optimization on the Byzantine Fault Tolerant algorithm. To quote Blockonomi: “In the context of distributed systems, Byzantine Fault Tolerance is the ability of a distributed computer network to function as desired and correctly reach a sufficient consensus despite malicious components (nodes) of the system failing or propagating incorrect information to other peers.” Zilliqa is such a distributed computer network and depends on the honesty of the nodes (shard and DS) to reach consensus and to continuously update the state with the latest block. If pBFT is a new term for you I can highly recommend the Blockonomi article.
 
The idea of pBFT was introduced in 1999 - one of the authors even won a Turing award for it - and it is well researched and applied in various blockchains and distributed systems nowadays. If you want more advanced information than the Blockonomi link provides click here. And if you’re in between Blockonomi and the University of Singapore read the Zilliqa Design Story Part 2 dating from October 2017.
Quoting from the Zilliqa tech whitepaper: “pBFT relies upon a correct leader (which is randomly selected) to begin each phase and proceed when the sufficient majority exists. In case the leader is byzantine it can stall the entire consensus protocol. To address this challenge, pBFT offers a view change protocol to replace the byzantine leader with another one.”
 
pBFT can tolerate ⅓ of the nodes being dishonest (offline counts as Byzantine = dishonest) and the consensus protocol will function without stalling or hiccups. Once there are more than ⅓ of dishonest nodes but no more than ⅔ the network will be stalled and a view change will be triggered to elect a new DS leader. Only when more than ⅔ of the nodes are dishonest (66%) double-spend attacks become possible.
 
If the network stalls no transactions can be processed and one has to wait until a new honest leader has been elected. When the mainnet was just launched and in its early phases, view changes happened regularly. As of today the last stalling of the network - and view change being triggered - was at the end of October 2019.
 
Another benefit of using pBFT for consensus besides low energy is the immediate finality it provides. Once your transaction is included in a block and the block is added to the chain it’s done. Lastly, take a look at this article where three types of finality are being defined: probabilistic, absolute and economic finality. Zilliqa falls under the absolute finality (just like Tendermint for example). Although lengthy already we skipped through some of the inner workings from Zilliqa’s consensus: read the Zilliqa Design Story Part 3 and you will be close to having a complete picture on it. Enough about PoW, sybil resistance mechanism, pBFT, etc. Another thing we haven’t looked at yet is the amount of decentralization.
 
Decentralisation
 
Currently, there are four shards, each one of them consisting of 600 nodes. 1 shard with 600 so-called DS nodes (Directory Service - they need to achieve a higher difficulty than shard nodes) and 1800 shard nodes of which 250 are shard guards (centralized nodes controlled by the team). The amount of shard guards has been steadily declining from 1200 in January 2019 to 250 as of May 2020. On the Viewblock statistics, you can see that many of the nodes are being located in the US but those are only the (CPU parts of the) shard nodes who perform pBFT. There is no data from where the PoW sources are coming. And when the Zilliqa blockchain starts reaching its transaction capacity limit, a network upgrade needs to be executed to lift the current cap of maximum 2400 nodes to allow more nodes and formation of more shards which will allow to network to keep on scaling according to demand.
Besides shard nodes there are also seed nodes. The main role of seed nodes is to serve as direct access points (for end-users and clients) to the core Zilliqa network that validates transactions. Seed nodes consolidate transaction requests and forward these to the lookup nodes (another type of nodes) for distribution to the shards in the network. Seed nodes also maintain the entire transaction history and the global state of the blockchain which is needed to provide services such as block explorers. Seed nodes in the Zilliqa network are comparable to Infura on Ethereum.
 
The seed nodes were first only operated by Zilliqa themselves, exchanges and Viewblock. Operators of seed nodes like exchanges had no incentive to open them for the greater public. They were centralised at first. Decentralisation at the seed nodes level has been steadily rolled out since March 2020 ( Zilliqa Improvement Proposal 3 ). Currently the amount of seed nodes is being increased, they are public-facing and at the same time PoS is applied to incentivize seed node operators and make it possible for ZIL holders to stake and earn passive yields. Important distinction: seed nodes are not involved with consensus! That is still PoW as entry ticket and pBFT for the actual consensus.
 
5% of the block rewards are being assigned to seed nodes (from the beginning in 2019) and those are being used to pay out ZIL stakers. The 5% block rewards with an annual yield of 10.03% translate to roughly 610 MM ZILs in total that can be staked. Exchanges use the custodial variant of staking and wallets like Moonlet will use the non-custodial version (starting in Q3 2020). Staking is being done by sending ZILs to a smart contract created by Zilliqa and audited by Quantstamp.
 
With a high amount of DS; shard nodes and seed nodes becoming more decentralized too, Zilliqa qualifies for the label of decentralized in my opinion.
 
Smart contracts
 
Let me start by saying I’m not a developer and my programming skills are quite limited. So I‘m taking the ELI5 route (maybe 12) but if you are familiar with Javascript, Solidity or specifically OCaml please head straight to Scilla - read the docs to get a good initial grasp of how Zilliqa’s smart contract language Scilla works and if you ask yourself “why another programming language?” check this article. And if you want to play around with some sample contracts in an IDE click here. The faucet can be found here. And more information on architecture, dapp development and API can be found on the Developer Portal.
If you are more into listening and watching: check this recent webinar explaining Zilliqa and Scilla. Link is time-stamped so you’ll start right away with a platform introduction, roadmap 2020 and afterwards a proper Scilla introduction.
 
Generalized: programming languages can be divided into being ‘object-oriented’ or ‘functional’. Here is an ELI5 given by software development academy: * “all programs have two basic components, data – what the program knows – and behavior – what the program can do with that data. So object-oriented programming states that combining data and related behaviors in one place, is called “object”, which makes it easier to understand how a particular program works. On the other hand, functional programming argues that data and behavior are different things and should be separated to ensure their clarity.” *
 
Scilla is on the functional side and shares similarities with OCaml: OCaml is a general-purpose programming language with an emphasis on expressiveness and safety. It has an advanced type system that helps catch your mistakes without getting in your way. It's used in environments where a single mistake can cost millions and speed matters, is supported by an active community, and has a rich set of libraries and development tools. For all its power, OCaml is also pretty simple, which is one reason it's often used as a teaching language.
 
Scilla is blockchain agnostic, can be implemented onto other blockchains as well, is recognized by academics and won a so-called Distinguished Artifact Award award at the end of last year.
 
One of the reasons why the Zilliqa team decided to create their own programming language focused on preventing smart contract vulnerabilities is that adding logic on a blockchain, programming, means that you cannot afford to make mistakes. Otherwise, it could cost you. It’s all great and fun blockchains being immutable but updating your code because you found a bug isn’t the same as with a regular web application for example. And with smart contracts, it inherently involves cryptocurrencies in some form thus value.
 
Another difference with programming languages on a blockchain is gas. Every transaction you do on a smart contract platform like Zilliqa or Ethereum costs gas. With gas you basically pay for computational costs. Sending a ZIL from address A to address B costs 0.001 ZIL currently. Smart contracts are more complex, often involve various functions and require more gas (if gas is a new concept click here ).
 
So with Scilla, similar to Solidity, you need to make sure that “every function in your smart contract will run as expected without hitting gas limits. An improper resource analysis may lead to situations where funds may get stuck simply because a part of the smart contract code cannot be executed due to gas limits. Such constraints are not present in traditional software systems”. Scilla design story part 1
 
Some examples of smart contract issues you’d want to avoid are: leaking funds, ‘unexpected changes to critical state variables’ (example: someone other than you setting his or her address as the owner of the smart contract after creation) or simply killing a contract.
 
Scilla also allows for formal verification. Wikipedia to the rescue: In the context of hardware and software systems, formal verification is the act of proving or disproving the correctness of intended algorithms underlying a system with respect to a certain formal specification or property, using formal methods of mathematics.
 
Formal verification can be helpful in proving the correctness of systems such as: cryptographic protocols, combinational circuits, digital circuits with internal memory, and software expressed as source code.
 
Scilla is being developed hand-in-hand with formalization of its semantics and its embedding into the Coq proof assistant — a state-of-the art tool for mechanized proofs about properties of programs.”
 
Simply put, with Scilla and accompanying tooling developers can be mathematically sure and proof that the smart contract they’ve written does what he or she intends it to do.
 
Smart contract on a sharded environment and state sharding
 
There is one more topic I’d like to touch on: smart contract execution in a sharded environment (and what is the effect of state sharding). This is a complex topic. I’m not able to explain it any easier than what is posted here. But I will try to compress the post into something easy to digest.
 
Earlier on we have established that Zilliqa can process transactions in parallel due to network sharding. This is where the linear scalability comes from. We can define simple transactions: a transaction from address A to B (Category 1), a transaction where a user interacts with one smart contract (Category 2) and the most complex ones where triggering a transaction results in multiple smart contracts being involved (Category 3). The shards are able to process transactions on their own without interference of the other shards. With Category 1 transactions that is doable, with Category 2 transactions sometimes if that address is in the same shard as the smart contract but with Category 3 you definitely need communication between the shards. Solving that requires to make a set of communication rules the protocol needs to follow in order to process all transactions in a generalised fashion.
 
And this is where the downsides of state sharding comes in currently. All shards in Zilliqa have access to the complete state. Yes the state size (0.1 GB at the moment) grows and all of the nodes need to store it but it also means that they don’t need to shop around for information available on other shards. Requiring more communication and adding more complexity. Computer science knowledge and/or developer knowledge required links if you want to dig further: Scilla - language grammar Scilla - Foundations for Verifiable Decentralised Computations on a Blockchain Gas Accounting NUS x Zilliqa: Smart contract language workshop
 
Easier to follow links on programming Scilla https://learnscilla.com/home Ivan on Tech
 
Roadmap / Zilliqa 2.0
 
There is no strict defined roadmap but here are topics being worked on. And via the Zilliqa website there is also more information on the projects they are working on.
 
Business & Partnerships
 
It’s not only technology in which Zilliqa seems to be excelling as their ecosystem has been expanding and starting to grow rapidly. The project is on a mission to provide OpenFinance (OpFi) to the world and Singapore is the right place to be due to its progressive regulations and futuristic thinking. Singapore has taken a proactive approach towards cryptocurrencies by introducing the Payment Services Act 2019 (PS Act). Among other things, the PS Act will regulate intermediaries dealing with certain cryptocurrencies, with a particular focus on consumer protection and anti-money laundering. It will also provide a stable regulatory licensing and operating framework for cryptocurrency entities, effectively covering all crypto businesses and exchanges based in Singapore. According to PWC 82% of the surveyed executives in Singapore reported blockchain initiatives underway and 13% of them have already brought the initiatives live to the market. There is also an increasing list of organizations that are starting to provide digital payment services. Moreover, Singaporean blockchain developers Building Cities Beyond has recently created an innovation $15 million grant to encourage development on its ecosystem. This all suggests that Singapore tries to position itself as (one of) the leading blockchain hubs in the world.
 
Zilliqa seems to already take advantage of this and recently helped launch Hg Exchange on their platform, together with financial institutions PhillipCapital, PrimePartners and Fundnel. Hg Exchange, which is now approved by the Monetary Authority of Singapore (MAS), uses smart contracts to represent digital assets. Through Hg Exchange financial institutions worldwide can use Zilliqa's safe-by-design smart contracts to enable the trading of private equities. For example, think of companies such as Grab, Airbnb, SpaceX that are not available for public trading right now. Hg Exchange will allow investors to buy shares of private companies & unicorns and capture their value before an IPO. Anquan, the main company behind Zilliqa, has also recently announced that they became a partner and shareholder in TEN31 Bank, which is a fully regulated bank allowing for tokenization of assets and is aiming to bridge the gap between conventional banking and the blockchain world. If STOs, the tokenization of assets, and equity trading will continue to increase, then Zilliqa’s public blockchain would be the ideal candidate due to its strategic positioning, partnerships, regulatory compliance and the technology that is being built on top of it.
 
What is also very encouraging is their focus on banking the un(der)banked. They are launching a stablecoin basket starting with XSGD. As many of you know, stablecoins are currently mostly used for trading. However, Zilliqa is actively trying to broaden the use case of stablecoins. I recommend everybody to read this text that Amrit Kumar wrote (one of the co-founders). These stablecoins will be integrated in the traditional markets and bridge the gap between the crypto world and the traditional world. This could potentially revolutionize and legitimise the crypto space if retailers and companies will for example start to use stablecoins for payments or remittances, instead of it solely being used for trading.
 
Zilliqa also released their DeFi strategic roadmap (dating November 2019) which seems to be aligning well with their OpFi strategy. A non-custodial DEX is coming to Zilliqa made by Switcheo which allows cross-chain trading (atomic swaps) between ETH, EOS and ZIL based tokens. They also signed a Memorandum of Understanding for a (soon to be announced) USD stablecoin. And as Zilliqa is all about regulations and being compliant, I’m speculating on it to be a regulated USD stablecoin. Furthermore, XSGD is already created and visible on block explorer and XIDR (Indonesian Stablecoin) is also coming soon via StraitsX. Here also an overview of the Tech Stack for Financial Applications from September 2019. Further quoting Amrit Kumar on this:
 
There are two basic building blocks in DeFi/OpFi though: 1) stablecoins as you need a non-volatile currency to get access to this market and 2) a dex to be able to trade all these financial assets. The rest are built on top of these blocks.
 
So far, together with our partners and community, we have worked on developing these building blocks with XSGD as a stablecoin. We are working on bringing a USD-backed stablecoin as well. We will soon have a decentralised exchange developed by Switcheo. And with HGX going live, we are also venturing into the tokenization space. More to come in the future.”
 
Additionally, they also have this ZILHive initiative that injects capital into projects. There have been already 6 waves of various teams working on infrastructure, innovation and research, and they are not from ASEAN or Singapore only but global: see Grantees breakdown by country. Over 60 project teams from over 20 countries have contributed to Zilliqa's ecosystem. This includes individuals and teams developing wallets, explorers, developer toolkits, smart contract testing frameworks, dapps, etc. As some of you may know, Unstoppable Domains (UD) blew up when they launched on Zilliqa. UD aims to replace cryptocurrency addresses with a human-readable name and allows for uncensorable websites. Zilliqa will probably be the only one able to handle all these transactions onchain due to ability to scale and its resulting low fees which is why the UD team launched this on Zilliqa in the first place. Furthermore, Zilliqa also has a strong emphasis on security, compliance, and privacy, which is why they partnered with companies like Elliptic, ChainSecurity (part of PwC Switzerland), and Incognito. Their sister company Aqilliz (Zilliqa spelled backwards) focuses on revolutionizing the digital advertising space and is doing interesting things like using Zilliqa to track outdoor digital ads with companies like Foodpanda.
 
Zilliqa is listed on nearly all major exchanges, having several different fiat-gateways and recently have been added to Binance’s margin trading and futures trading with really good volume. They also have a very impressive team with good credentials and experience. They don't just have “tech people”. They have a mix of tech people, business people, marketeers, scientists, and more. Naturally, it's good to have a mix of people with different skill sets if you work in the crypto space.
 
Marketing & Community
 
Zilliqa has a very strong community. If you just follow their Twitter their engagement is much higher for a coin that has approximately 80k followers. They also have been ‘coin of the day’ by LunarCrush many times. LunarCrush tracks real-time cryptocurrency value and social data. According to their data, it seems Zilliqa has a more fundamental and deeper understanding of marketing and community engagement than almost all other coins. While almost all coins have been a bit frozen in the last months, Zilliqa seems to be on its own bull run. It was somewhere in the 100s a few months ago and is currently ranked #46 on CoinGecko. Their official Telegram also has over 20k people and is very active, and their community channel which is over 7k now is more active and larger than many other official channels. Their local communities also seem to be growing.
 
Moreover, their community started ‘Zillacracy’ together with the Zilliqa core team ( see www.zillacracy.com ). It’s a community-run initiative where people from all over the world are now helping with marketing and development on Zilliqa. Since its launch in February 2020 they have been doing a lot and will also run their own non-custodial seed node for staking. This seed node will also allow them to start generating revenue for them to become a self sustaining entity that could potentially scale up to become a decentralized company working in parallel with the Zilliqa core team. Comparing it to all the other smart contract platforms (e.g. Cardano, EOS, Tezos etc.) they don't seem to have started a similar initiative (correct me if I’m wrong though). This suggests in my opinion that these other smart contract platforms do not fully understand how to utilize the ‘power of the community’. This is something you cannot ‘buy with money’ and gives many projects in the space a disadvantage.
 
Zilliqa also released two social products called SocialPay and Zeeves. SocialPay allows users to earn ZILs while tweeting with a specific hashtag. They have recently used it in partnership with the Singapore Red Cross for a marketing campaign after their initial pilot program. It seems like a very valuable social product with a good use case. I can see a lot of traditional companies entering the space through this product, which they seem to suggest will happen. Tokenizing hashtags with smart contracts to get network effect is a very smart and innovative idea.
 
Regarding Zeeves, this is a tipping bot for Telegram. They already have 1000s of signups and they plan to keep upgrading it for more and more people to use it (e.g. they recently have added a quiz features). They also use it during AMAs to reward people in real-time. It’s a very smart approach to grow their communities and get familiar with ZIL. I can see this becoming very big on Telegram. This tool suggests, again, that the Zilliqa team has a deeper understanding of what the crypto space and community needs and is good at finding the right innovative tools to grow and scale.
 
To be honest, I haven’t covered everything (i’m also reaching the character limited haha). So many updates happening lately that it's hard to keep up, such as the International Monetary Fund mentioning Zilliqa in their report, custodial and non-custodial Staking, Binance Margin, Futures, Widget, entering the Indian market, and more. The Head of Marketing Colin Miles has also released this as an overview of what is coming next. And last but not least, Vitalik Buterin has been mentioning Zilliqa lately acknowledging Zilliqa and mentioning that both projects have a lot of room to grow. There is much more info of course and a good part of it has been served to you on a silver platter. I invite you to continue researching by yourself :-) And if you have any comments or questions please post here!
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Namecoin and the future of self-sovereign digital identity.

Namecoin's motto is "Bitcoin frees money – Namecoin frees DNS, identities, and other technologies."
biolizard89 has done fantastic work on the DNS part, but let's focus on the identity use case here. Recent events have convinced me that digital identity on the internet is broken. Consider:
What was true in 1993 when cartoonist Peter Steiner wrote "On the internet, nobody knows you are a dog" is still true today. The only difference is that identity is increasingly being weaponized using AI/ML so "On the internet, nobody knows you are a bot" would perhaps be more apt.
I read the following comment from a user on slashdot yesterday:
For the time being, you can assume that this comment was written by a human being. You can click on my username, look back at my history of posts, and go, "OK, here's a bunch of posts, by a person, going back more than a decade, to the TIME BEFORE BOTS." That is, before the first year of 2020.
Since humans are likely to adopt the majority opinion, bad actors find real value in being able to control the narrative online by surrounding the reader with manufactured opinions by bots that due to advances in ML/AI are quickly becoming indistinguishable from real users. This amounts to a Sybil attack on the minds of digital content consumers and poses major threat to the integrity of our social fabric.
Apart from the recent twitter incident used for scamming, nation states have been known to create massive bot armies of fake and hijacked user accounts to try and shift the narratives regarding the Hong Kong independence protests as well as national elections. This will only increase.
Currently, our digital identity is fragmented into silo's largely controlled by government institutions and mega corporations (FAANG) based on a "Trust us" model. As recent events have proven, this is a bad model and in dire need of improvement/replacement. IMHO we need to move from "Trust us" to a "Trust but verify" model where the user is in full control of their digital identity.
Namecoin can and should play an important role in building this 'web of trust composed of self-sovereign identities" as it is neutral (no owner), permissionless and secure (merge-mined). Daniel already developed a proof of concept with NameID but what can we do to take this further?
Personally I'd like to see users create Namecoin identities and link them to their social identities (e.g. Google, Facebook, Twitter, Reddit, etc). Then whenever they create content, they sign it with their private keys. This would allow a reader to verify the content was created by the user. Content verification would have stopped the recent twitter hack, because even if the hackers would have access to internal admin tools they would not have the private keys that the users produce valid content with. "Not your keys, not your content"
Content verification is only one part. Ideally a user would like to verify the integrity of the content creator as well. E.g. has this user passed human verification in any of the linked platforms? Does a trusted linked entity vouch for the reputation or integrity of this user (e.g. a government entity, financial entity or non-governmental organization?). This would require those platforms to allow linking of Namecoin ID with their Platform ID and allow lookup and signing of metadata provided by these platforms. (e.g. UserID Y is linked to PlatformID X and completed human verification on date Z, signed Twitter).
I image users could install an extension similar to uBlock or Privacy Badger that contains human curated blacklists and heuristics that operate on Namecoin entities to perform these checks and flag or filter content and users that fail integrity checks. This would allow a users to automatically weed out potential bots and trolls but keep full control of this process themselves, avoiding potential censorship if this task would fall on the platform owners themselves (something governments are pushing for).
We could take this even further and integrate Namecoin ID's in software and hardware devices as well. This could create chains of trust to verify the entire chain of content creation and manipulation to the final content posted on a social platform. Where every entity signs the resulting content. (E.g. camera -> photoshop -> twitter post)
Apart from signing content/messages (PGP style). Namecoin could perhaps also be used for managing identity tokens in a users 'Identity wallet'. Looking into my physical wallet this could include things like credit cards, insurance cards, government issued IDs, membership cards, transportation cards, key cards, etc. This could be done similar to 'colored coins' on Bitcoin. But would have to support some type of smart contract functionality to be useful (e.g. expiring tokens, etc).
I'm not a developer nor a technical writer, but I do think we need to think long and hard about how we can solve digital identity in a way that empowers users to trust and verify the content and identities of the peers we interact with online while also respecting privacy and preventing censorship by external parties. Namecoin could be the better path to building this web of trust, but given the current pace of AI/ML and the willingness by bad actors to weaponize it at scale against users interests we might not have much time. (Apologies for the rant!)
submitted by rmvaandr to Namecoin [link] [comments]

Why i’m bullish on Zilliqa (long read)

Hey all, I've been researching coins since 2017 and have gone through 100s of them in the last 3 years. I got introduced to blockchain via Bitcoin of course, analysed Ethereum thereafter and from that moment I have a keen interest in smart contact platforms. I’m passionate about Ethereum but I find Zilliqa to have a better risk reward ratio. Especially because Zilliqa has found an elegant balance between being secure, decentralised and scalable in my opinion.
 
Below I post my analysis why from all the coins I went through I’m most bullish on Zilliqa (yes I went through Tezos, EOS, NEO, VeChain, Harmony, Algorand, Cardano etc.). Note that this is not investment advice and although it's a thorough analysis there is obviously some bias involved. Looking forward to what you all think!
 
Fun fact: the name Zilliqa is a play on ‘silica’ silicon dioxide which means “Silicon for the high-throughput consensus computer.”
 
This post is divided into (i) Technology, (ii) Business & Partnerships, and (iii) Marketing & Community. I’ve tried to make the technology part readable for a broad audience. If you’ve ever tried understanding the inner workings of Bitcoin and Ethereum you should be able to grasp most parts. Otherwise just skim through and once you are zoning out head to the next part.
 
Technology and some more:
 
Introduction The technology is one of the main reasons why I’m so bullish on Zilliqa. First thing you see on their website is: “Zilliqa is a high-performance, high-security blockchain platform for enterprises and next-generation applications.” These are some bold statements.
 
Before we deep dive into the technology let’s take a step back in time first as they have quite the history. The initial research paper from which Zilliqa originated dates back to August 2016: Elastico: A Secure Sharding Protocol For Open Blockchains where Loi Luu (Kyber Network) is one of the co-authors. Other ideas that led to the development of what Zilliqa has become today are: Bitcoin-NG, collective signing CoSi, ByzCoin and Omniledger.
 
The technical white paper was made public in August 2017 and since then they have achieved everything stated in the white paper and also created their own open source intermediate level smart contract language called Scilla (functional programming language similar to OCaml) too.
 
Mainnet is live since end of January 2019 with daily transaction rate growing continuously. About a week ago mainnet reached 5 million transactions, 500.000+ addresses in total along with 2400 nodes keeping the network decentralised and secure. Circulating supply is nearing 11 billion and currently only mining rewards are left. Maximum supply is 21 billion with annual inflation being 7.13% currently and will only decrease with time.
 
Zilliqa realised early on that the usage of public cryptocurrencies and smart contracts were increasing but decentralised, secure and scalable alternatives were lacking in the crypto space. They proposed to apply sharding onto a public smart contract blockchain where the transaction rate increases almost linear with the increase in amount of nodes. More nodes = higher transaction throughput and increased decentralisation. Sharding comes in many forms and Zilliqa uses network-, transaction- and computational sharding. Network sharding opens up the possibility of using transaction- and computational sharding on top. Zilliqa does not use state sharding for now. We’ll come back to this later.
 
Before we continue disecting how Zilliqa achieves such from a technological standpoint it’s good to keep in mind that a blockchain being decentralised and secure and scalable is still one of the main hurdles in allowing widespread usage of decentralised networks. In my opinion this needs to be solved first before blockchains can get to the point where they can create and add large scale value. So I invite you to read the next section to grasp the underlying fundamentals. Because after all these premises need to be true otherwise there isn’t a fundamental case to be bullish on Zilliqa, right?
 
Down the rabbit hole
 
How have they achieved this? Let’s define the basics first: key players on Zilliqa are the users and the miners. A user is anybody who uses the blockchain to transfer funds or run smart contracts. Miners are the (shard) nodes in the network who run the consensus protocol and get rewarded for their service in Zillings (ZIL). The mining network is divided into several smaller networks called shards, which is also referred to as ‘network sharding’. Miners subsequently are randomly assigned to a shard by another set of miners called DS (Directory Service) nodes. The regular shards process transactions and the outputs of these shards are eventually combined by the DS shard as they reach consensus on the final state. More on how these DS shards reach consensus (via pBFT) will be explained later on.
 
The Zilliqa network produces two types of blocks: DS blocks and Tx blocks. One DS Block consists of 100 Tx Blocks. And as previously mentioned there are two types of nodes concerned with reaching consensus: shard nodes and DS nodes. Becoming a shard node or DS node is being defined by the result of a PoW cycle (Ethash) at the beginning of the DS Block. All candidate mining nodes compete with each other and run the PoW (Proof-of-Work) cycle for 60 seconds and the submissions achieving the highest difficulty will be allowed on the network. And to put it in perspective: the average difficulty for one DS node is ~ 2 Th/s equaling 2.000.000 Mh/s or 55 thousand+ GeForce GTX 1070 / 8 GB GPUs at 35.4 Mh/s. Each DS Block 10 new DS nodes are allowed. And a shard node needs to provide around 8.53 GH/s currently (around 240 GTX 1070s). Dual mining ETH/ETC and ZIL is possible and can be done via mining software such as Phoenix and Claymore. There are pools and if you have large amounts of hashing power (Ethash) available you could mine solo.
 
The PoW cycle of 60 seconds is a peak performance and acts as an entry ticket to the network. The entry ticket is called a sybil resistance mechanism and makes it incredibly hard for adversaries to spawn lots of identities and manipulate the network with these identities. And after every 100 Tx Blocks which corresponds to roughly 1,5 hour this PoW process repeats. In between these 1,5 hour no PoW needs to be done meaning Zilliqa’s energy consumption to keep the network secure is low. For more detailed information on how mining works click here.
Okay, hats off to you. You have made it this far. Before we go any deeper down the rabbit hole we first must understand why Zilliqa goes through all of the above technicalities and understand a bit more what a blockchain on a more fundamental level is. Because the core of Zilliqa’s consensus protocol relies on the usage of pBFT (practical Byzantine Fault Tolerance) we need to know more about state machines and their function. Navigate to Viewblock, a Zilliqa block explorer, and just come back to this article. We will use this site to navigate through a few concepts.
 
We have established that Zilliqa is a public and distributed blockchain. Meaning that everyone with an internet connection can send ZILs, trigger smart contracts etc. and there is no central authority who fully controls the network. Zilliqa and other public and distributed blockchains (like Bitcoin and Ethereum) can also be defined as state machines.
 
Taking the liberty of paraphrasing examples and definitions given by Samuel Brooks’ medium article, he describes the definition of a blockchain (like Zilliqa) as:
“A peer-to-peer, append-only datastore that uses consensus to synchronise cryptographically-secure data”.
 
Next he states that: >“blockchains are fundamentally systems for managing valid state transitions”.* For some more context, I recommend reading the whole medium article to get a better grasp of the definitions and understanding of state machines. Nevertheless, let’s try to simplify and compile it into a single paragraph. Take traffic lights as an example: all its states (red, amber and green) are predefined, all possible outcomes are known and it doesn’t matter if you encounter the traffic light today or tomorrow. It will still behave the same. Managing the states of a traffic light can be done by triggering a sensor on the road or pushing a button resulting in one traffic lights’ state going from green to red (via amber) and another light from red to green.
 
With public blockchains like Zilliqa this isn’t so straightforward and simple. It started with block #1 almost 1,5 years ago and every 45 seconds or so a new block linked to the previous block is being added. Resulting in a chain of blocks with transactions in it that everyone can verify from block #1 to the current #647.000+ block. The state is ever changing and the states it can find itself in are infinite. And while the traffic light might work together in tandem with various other traffic lights, it’s rather insignificant comparing it to a public blockchain. Because Zilliqa consists of 2400 nodes who need to work together to achieve consensus on what the latest valid state is while some of these nodes may have latency or broadcast issues, drop offline or are deliberately trying to attack the network etc.
 
Now go back to the Viewblock page take a look at the amount of transaction, addresses, block and DS height and then hit refresh. Obviously as expected you see new incremented values on one or all parameters. And how did the Zilliqa blockchain manage to transition from a previous valid state to the latest valid state? By using pBFT to reach consensus on the latest valid state.
 
After having obtained the entry ticket, miners execute pBFT to reach consensus on the ever changing state of the blockchain. pBFT requires a series of network communication between nodes, and as such there is no GPU involved (but CPU). Resulting in the total energy consumed to keep the blockchain secure, decentralised and scalable being low.
 
pBFT stands for practical Byzantine Fault Tolerance and is an optimisation on the Byzantine Fault Tolerant algorithm. To quote Blockonomi: “In the context of distributed systems, Byzantine Fault Tolerance is the ability of a distributed computer network to function as desired and correctly reach a sufficient consensus despite malicious components (nodes) of the system failing or propagating incorrect information to other peers.” Zilliqa is such a distributed computer network and depends on the honesty of the nodes (shard and DS) to reach consensus and to continuously update the state with the latest block. If pBFT is a new term for you I can highly recommend the Blockonomi article.
 
The idea of pBFT was introduced in 1999 - one of the authors even won a Turing award for it - and it is well researched and applied in various blockchains and distributed systems nowadays. If you want more advanced information than the Blockonomi link provides click here. And if you’re in between Blockonomi and University of Singapore read the Zilliqa Design Story Part 2 dating from October 2017.
Quoting from the Zilliqa tech whitepaper: “pBFT relies upon a correct leader (which is randomly selected) to begin each phase and proceed when the sufficient majority exists. In case the leader is byzantine it can stall the entire consensus protocol. To address this challenge, pBFT offers a view change protocol to replace the byzantine leader with another one.”
 
pBFT can tolerate ⅓ of the nodes being dishonest (offline counts as Byzantine = dishonest) and the consensus protocol will function without stalling or hiccups. Once there are more than ⅓ of dishonest nodes but no more than ⅔ the network will be stalled and a view change will be triggered to elect a new DS leader. Only when more than ⅔ of the nodes are dishonest (>66%) double spend attacks become possible.
 
If the network stalls no transactions can be processed and one has to wait until a new honest leader has been elected. When the mainnet was just launched and in its early phases, view changes happened regularly. As of today the last stalling of the network - and view change being triggered - was at the end of October 2019.
 
Another benefit of using pBFT for consensus besides low energy is the immediate finality it provides. Once your transaction is included in a block and the block is added to the chain it’s done. Lastly, take a look at this article where three types of finality are being defined: probabilistic, absolute and economic finality. Zilliqa falls under the absolute finality (just like Tendermint for example). Although lengthy already we skipped through some of the inner workings from Zilliqa’s consensus: read the Zilliqa Design Story Part 3 and you will be close to having a complete picture on it. Enough about PoW, sybil resistance mechanism, pBFT etc. Another thing we haven’t looked at yet is the amount of decentralisation.
 
Decentralisation
 
Currently there are four shards, each one of them consisting of 600 nodes. 1 shard with 600 so called DS nodes (Directory Service - they need to achieve a higher difficulty than shard nodes) and 1800 shard nodes of which 250 are shard guards (centralised nodes controlled by the team). The amount of shard guards has been steadily declining from 1200 in January 2019 to 250 as of May 2020. On the Viewblock statistics you can see that many of the nodes are being located in the US but those are only the (CPU parts of the) shard nodes who perform pBFT. There is no data from where the PoW sources are coming. And when the Zilliqa blockchain starts reaching their transaction capacity limit, a network upgrade needs to be executed to lift the current cap of maximum 2400 nodes to allow more nodes and formation of more shards which will allow to network to keep on scaling according to demand.
Besides shard nodes there are also seed nodes. The main role of seed nodes is to serve as direct access points (for end users and clients) to the core Zilliqa network that validates transactions. Seed nodes consolidate transaction requests and forward these to the lookup nodes (another type of nodes) for distribution to the shards in the network. Seed nodes also maintain the entire transaction history and the global state of the blockchain which is needed to provide services such as block explorers. Seed nodes in the Zilliqa network are comparable to Infura on Ethereum.
 
The seed nodes were first only operated by Zilliqa themselves, exchanges and Viewblock. Operators of seed nodes like exchanges had no incentive to open them for the greater public.They were centralised at first. Decentralisation at the seed nodes level has been steadily rolled out since March 2020 ( Zilliqa Improvement Proposal 3 ). Currently the amount of seed nodes is being increased, they are public facing and at the same time PoS is applied to incentivize seed node operators and make it possible for ZIL holders to stake and earn passive yields. Important distinction: seed nodes are not involved with consensus! That is still PoW as entry ticket and pBFT for the actual consensus.
 
5% of the block rewards are being assigned to seed nodes (from the beginning in 2019) and those are being used to pay out ZIL stakers.The 5% block rewards with an annual yield of 10.03% translates to roughly 610 MM ZILs in total that can be staked. Exchanges use the custodial variant of staking and wallets like Moonlet will use the non custodial version (starting in Q3 2020). Staking is being done by sending ZILs to a smart contract created by Zilliqa and audited by Quantstamp.
 
With a high amount of DS & shard nodes and seed nodes becoming more decentralised too, Zilliqa qualifies for the label of decentralised in my opinion.
 
Smart contracts
 
Let me start by saying I’m not a developer and my programming skills are quite limited. So I‘m taking the ELI5 route (maybe 12) but if you are familiar with Javascript, Solidity or specifically OCaml please head straight to Scilla - read the docs to get a good initial grasp of how Zilliqa’s smart contract language Scilla works and if you ask yourself “why another programming language?” check this article. And if you want to play around with some sample contracts in an IDE click here. Faucet can be found here. And more information on architecture, dapp development and API can be found on the Developer Portal.
If you are more into listening and watching: check this recent webinar explaining Zilliqa and Scilla. Link is time stamped so you’ll start right away with a platform introduction, R&D roadmap 2020 and afterwards a proper Scilla introduction.
 
Generalised: programming languages can be divided into being ‘object oriented’ or ‘functional’. Here is an ELI5 given by software development academy: > “all programmes have two basic components, data – what the programme knows – and behaviour – what the programme can do with that data. So object-oriented programming states that combining data and related behaviours in one place, is called “object”, which makes it easier to understand how a particular program works. On the other hand, functional programming argues that data and behaviour are different things and should be separated to ensure their clarity.”
 
Scilla is on the functional side and shares similarities with OCaml: > OCaml is a general purpose programming language with an emphasis on expressiveness and safety. It has an advanced type system that helps catch your mistakes without getting in your way. It's used in environments where a single mistake can cost millions and speed matters, is supported by an active community, and has a rich set of libraries and development tools. For all its power, OCaml is also pretty simple, which is one reason it's often used as a teaching language.
 
Scilla is blockchain agnostic, can be implemented onto other blockchains as well, is recognised by academics and won a so called Distinguished Artifact Award award at the end of last year.
 
One of the reasons why the Zilliqa team decided to create their own programming language focused on preventing smart contract vulnerabilities safety is that adding logic on a blockchain, programming, means that you cannot afford to make mistakes. Otherwise it could cost you. It’s all great and fun blockchains being immutable but updating your code because you found a bug isn’t the same as with a regular web application for example. And with smart contracts it inherently involves cryptocurrencies in some form thus value.
 
Another difference with programming languages on a blockchain is gas. Every transaction you do on a smart contract platform like Zilliqa for Ethereum costs gas. With gas you basically pay for computational costs. Sending a ZIL from address A to address B costs 0.001 ZIL currently. Smart contracts are more complex, often involve various functions and require more gas (if gas is a new concept click here ).
 
So with Scilla, similar to Solidity, you need to make sure that “every function in your smart contract will run as expected without hitting gas limits. An improper resource analysis may lead to situations where funds may get stuck simply because a part of the smart contract code cannot be executed due to gas limits. Such constraints are not present in traditional software systems”. Scilla design story part 1
 
Some examples of smart contract issues you’d want to avoid are: leaking funds, ‘unexpected changes to critical state variables’ (example: someone other than you setting his or her address as the owner of the smart contract after creation) or simply killing a contract.
 
Scilla also allows for formal verification. Wikipedia to the rescue:
In the context of hardware and software systems, formal verification is the act of proving or disproving the correctness of intended algorithms underlying a system with respect to a certain formal specification or property, using formal methods of mathematics.
 
Formal verification can be helpful in proving the correctness of systems such as: cryptographic protocols, combinational circuits, digital circuits with internal memory, and software expressed as source code.
 
Scilla is being developed hand-in-hand with formalization of its semantics and its embedding into the Coq proof assistant — a state-of-the art tool for mechanized proofs about properties of programs.”
 
Simply put, with Scilla and accompanying tooling developers can be mathematically sure and proof that the smart contract they’ve written does what he or she intends it to do.
 
Smart contract on a sharded environment and state sharding
 
There is one more topic I’d like to touch on: smart contract execution in a sharded environment (and what is the effect of state sharding). This is a complex topic. I’m not able to explain it any easier than what is posted here. But I will try to compress the post into something easy to digest.
 
Earlier on we have established that Zilliqa can process transactions in parallel due to network sharding. This is where the linear scalability comes from. We can define simple transactions: a transaction from address A to B (Category 1), a transaction where a user interacts with one smart contract (Category 2) and the most complex ones where triggering a transaction results in multiple smart contracts being involved (Category 3). The shards are able to process transactions on their own without interference of the other shards. With Category 1 transactions that is doable, with Category 2 transactions sometimes if that address is in the same shard as the smart contract but with Category 3 you definitely need communication between the shards. Solving that requires to make a set of communication rules the protocol needs to follow in order to process all transactions in a generalised fashion.
 
And this is where the downsides of state sharding comes in currently. All shards in Zilliqa have access to the complete state. Yes the state size (0.1 GB at the moment) grows and all of the nodes need to store it but it also means that they don’t need to shop around for information available on other shards. Requiring more communication and adding more complexity. Computer science knowledge and/or developer knowledge required links if you want to dig further: Scilla - language grammar Scilla - Foundations for Verifiable Decentralised Computations on a Blockchain Gas Accounting NUS x Zilliqa: Smart contract language workshop
 
Easier to follow links on programming Scilla https://learnscilla.com/home Ivan on Tech
 
Roadmap / Zilliqa 2.0
 
There is no strict defined roadmap but here are topics being worked on. And via the Zilliqa website there is also more information on the projects they are working on.
 
Business & Partnerships  
It’s not only technology in which Zilliqa seems to be excelling as their ecosystem has been expanding and starting to grow rapidly. The project is on a mission to provide OpenFinance (OpFi) to the world and Singapore is the right place to be due to its progressive regulations and futuristic thinking. Singapore has taken a proactive approach towards cryptocurrencies by introducing the Payment Services Act 2019 (PS Act). Among other things, the PS Act will regulate intermediaries dealing with certain cryptocurrencies, with a particular focus on consumer protection and anti-money laundering. It will also provide a stable regulatory licensing and operating framework for cryptocurrency entities, effectively covering all crypto businesses and exchanges based in Singapore. According to PWC 82% of the surveyed executives in Singapore reported blockchain initiatives underway and 13% of them have already brought the initiatives live to the market. There is also an increasing list of organisations that are starting to provide digital payment services. Moreover, Singaporean blockchain developers Building Cities Beyond has recently created an innovation $15 million grant to encourage development on its ecosystem. This all suggest that Singapore tries to position itself as (one of) the leading blockchain hubs in the world.
 
Zilliqa seems to already taking advantage of this and recently helped launch Hg Exchange on their platform, together with financial institutions PhillipCapital, PrimePartners and Fundnel. Hg Exchange, which is now approved by the Monetary Authority of Singapore (MAS), uses smart contracts to represent digital assets. Through Hg Exchange financial institutions worldwide can use Zilliqa's safe-by-design smart contracts to enable the trading of private equities. For example, think of companies such as Grab, AirBnB, SpaceX that are not available for public trading right now. Hg Exchange will allow investors to buy shares of private companies & unicorns and capture their value before an IPO. Anquan, the main company behind Zilliqa, has also recently announced that they became a partner and shareholder in TEN31 Bank, which is a fully regulated bank allowing for tokenization of assets and is aiming to bridge the gap between conventional banking and the blockchain world. If STOs, the tokenization of assets, and equity trading will continue to increase, then Zilliqa’s public blockchain would be the ideal candidate due to its strategic positioning, partnerships, regulatory compliance and the technology that is being built on top of it.
 
What is also very encouraging is their focus on banking the un(der)banked. They are launching a stablecoin basket starting with XSGD. As many of you know, stablecoins are currently mostly used for trading. However, Zilliqa is actively trying to broaden the use case of stablecoins. I recommend everybody to read this text that Amrit Kumar wrote (one of the co-founders). These stablecoins will be integrated in the traditional markets and bridge the gap between the crypto world and the traditional world. This could potentially revolutionize and legitimise the crypto space if retailers and companies will for example start to use stablecoins for payments or remittances, instead of it solely being used for trading.
 
Zilliqa also released their DeFi strategic roadmap (dating November 2019) which seems to be aligning well with their OpFi strategy. A non-custodial DEX is coming to Zilliqa made by Switcheo which allows cross-chain trading (atomic swaps) between ETH, EOS and ZIL based tokens. They also signed a Memorandum of Understanding for a (soon to be announced) USD stablecoin. And as Zilliqa is all about regulations and being compliant, I’m speculating on it to be a regulated USD stablecoin. Furthermore, XSGD is already created and visible on block explorer and XIDR (Indonesian Stablecoin) is also coming soon via StraitsX. Here also an overview of the Tech Stack for Financial Applications from September 2019. Further quoting Amrit Kumar on this:
 
There are two basic building blocks in DeFi/OpFi though: 1) stablecoins as you need a non-volatile currency to get access to this market and 2) a dex to be able to trade all these financial assets. The rest are build on top of these blocks.
 
So far, together with our partners and community, we have worked on developing these building blocks with XSGD as a stablecoin. We are working on bringing a USD-backed stablecoin as well. We will soon have a decentralised exchange developed by Switcheo. And with HGX going live, we are also venturing into the tokenization space. More to come in the future.”*
 
Additionally, they also have this ZILHive initiative that injects capital into projects. There have been already 6 waves of various teams working on infrastructure, innovation and research, and they are not from ASEAN or Singapore only but global: see Grantees breakdown by country. Over 60 project teams from over 20 countries have contributed to Zilliqa's ecosystem. This includes individuals and teams developing wallets, explorers, developer toolkits, smart contract testing frameworks, dapps, etc. As some of you may know, Unstoppable Domains (UD) blew up when they launched on Zilliqa. UD aims to replace cryptocurrency addresses with a human readable name and allows for uncensorable websites. Zilliqa will probably be the only one able to handle all these transactions onchain due to ability to scale and its resulting low fees which is why the UD team launched this on Zilliqa in the first place. Furthermore, Zilliqa also has a strong emphasis on security, compliance, and privacy, which is why they partnered with companies like Elliptic, ChainSecurity (part of PwC Switzerland), and Incognito. Their sister company Aqilliz (Zilliqa spelled backwards) focuses on revolutionizing the digital advertising space and is doing interesting things like using Zilliqa to track outdoor digital ads with companies like Foodpanda.
 
Zilliqa is listed on nearly all major exchanges, having several different fiat-gateways and recently have been added to Binance’s margin trading and futures trading with really good volume. They also have a very impressive team with good credentials and experience. They dont just have “tech people”. They have a mix of tech people, business people, marketeers, scientists, and more. Naturally, it's good to have a mix of people with different skill sets if you work in the crypto space.
 
Marketing & Community
 
Zilliqa has a very strong community. If you just follow their Twitter their engagement is much higher for a coin that has approximately 80k followers. They also have been ‘coin of the day’ by LunarCrush many times. LunarCrush tracks real-time cryptocurrency value and social data. According to their data it seems Zilliqa has a more fundamental and deeper understanding of marketing and community engagement than almost all other coins. While almost all coins have been a bit frozen in the last months, Zilliqa seems to be on its own bull run. It was somewhere in the 100s a few months ago and is currently ranked #46 on CoinGecko. Their official Telegram also has over 20k people and is very active, and their community channel which is over 7k now is more active and larger than many other official channels. Their local communities) also seem to be growing.
 
Moreover, their community started ‘Zillacracy’ together with the Zilliqa core team ( see www.zillacracy.com ). It’s a community run initiative where people from all over the world are now helping with marketing and development on Zilliqa. Since its launch in February 2020 they have been doing a lot and will also run their own non custodial seed node for staking. This seed node will also allow them to start generating revenue for them to become a self sustaining entity that could potentially scale up to become a decentralized company working in parallel with the Zilliqa core team. Comparing it to all the other smart contract platforms (e.g. Cardano, EOS, Tezos etc.) they don't seem to have started a similar initiatives (correct me if I’m wrong though). This suggest in my opinion that these other smart contract platforms do not fully understand how to utilize the ‘power of the community’. This is something you cannot ‘buy with money’ and gives many projects in the space a disadvantage.
 
Zilliqa also released two social products called SocialPay and Zeeves. SocialPay allows users to earn ZILs while tweeting with a specific hashtag. They have recently used it in partnership with the Singapore Red Cross for a marketing campaign after their initial pilot program. It seems like a very valuable social product with a good use case. I can see a lot of traditional companies entering the space through this product, which they seem to suggest will happen. Tokenizing hashtags with smart contracts to get network effect is a very smart and innovative idea.
 
Regarding Zeeves, this is a tipping bot for Telegram. They already have 1000s of signups and they plan to keep upgrading it for more and more people to use it (e.g. they recently have added a quiz features). They also use it during AMAs to reward people in real time. It’s a very smart approach to grow their communities and get familiar with ZIL. I can see this becoming very big on Telegram. This tool suggests, again, that the Zilliqa team has a deeper understanding what the crypto space and community needs and is good at finding the right innovative tools to grow and scale.
 
To be honest, I haven’t covered everything (i’m also reaching the character limited haha). So many updates happening lately that it's hard to keep up, such as the International Monetary Fund mentioning Zilliqa in their report, custodial and non-custodial Staking, Binance Margin, Futures & Widget, entering the Indian market, and more. The Head of Marketing Colin Miles has also released this as an overview of what is coming next. And last but not least, Vitalik Buterin has been mentioning Zilliqa lately acknowledging Zilliqa and mentioning that both projects have a lot of room to grow. There is much more info of course and a good part of it has been served to you on a silver platter. I invite you to continue researching by yourself :-) And if you have any comments or questions please post here!
submitted by haveyouheardaboutit to CryptoCurrency [link] [comments]

Why don't bitcoin nodes use hole punching to get around NAT?

While Bitcoin only has about 10,000 public full nodes, this is only 10% of the nodes in the network. There are about 100,000 full nodes in the network. However, public full nodes are a bit of a bottleneck. All traffic received or sent by the 90% of the network that isn't public goes through a public node, which means the public nodes are transmitting about 10 times the traffic that private nodes do. The smaller number makes the network vulnerable to sybil attacks by well-funded attackers.
My question is: why doesn't Bitcoin more aggressively use hole punching) to increase the number of public nodes? There is a UPnP option in the settings for a bitcoin node, but its off by default, presumably because of a vulnerability found in 2015. However, that vulnerability has since been fixed, but the option remains off by default.
Is there a reason that this option is kept off by default? And is there a reason other hole punching techniques aren't being used?
submitted by fresheneesz to BitcoinDiscussion [link] [comments]

You know all those, low quality, aggressive, badly spelled "bcash lol" type comments... they really could be created by software.

Someone posted this Gizmodo article (archive) over on monero . It's about using a Weak-AI to automatically generate sentences that appear to be from humans. The claim is that the OpenAI organisation created and trained such a Weak-AI system. They then fed the Weak-AI the following made up news story as input:
In a shocking finding, scientist discovered a herd of unicorns living in a remote, previously unexplored valley, in the Andes Mountains. Even more surprising to the researchers was the fact that the unicorns spoke perfect English.
The Weak-AI then reportedly, wrote the following all by itself:
The scientist named the population, after their distinctive horn, Ovid’s Unicorn. These four-horned, silver-white unicorns were previously unknown to science.
Now, after almost two centuries, the mystery of what sparked this odd phenomenon is finally solved.
Dr. Jorge Pérez, an evolutionary biologist from the University of La Paz, and several companions, were exploring the Andes Mountains when they found a small valley, with no other animals or humans. Pérez noticed that the valley had what appeared to be a natural fountain, surrounded by two peaks of rock and silver snow.
This story seems plausible to me considering that NVIDIA have recently managed to create a Weak-AI that can create photo realistic human faces. Overview video here. This is something I consider to be even more difficult to pull off than a machine that can create human-like text sentences.
Now consider the quality of the typical "bcash lol" or "BSV is teh reel bitcoin" comment that this sub is showered with. It's far lower quality than the quoted paragraph above.
Imagine you are tasked with manipulating a large community which can't be easily penetrated from the upper levels (as seems to have happened to bitcoin , Bitcoin Core, bitcointalk bitcoin.org etc etc). A Sybil Attack is probably one of your best options now. Create division, create in-fighting, create the illusion of popular hatred for your community and project, using lots of cheaply created, fake accounts. Hiring tons of people to do this manually is expensive and makes you vulnerable to having your operation exposed. It would likely be far cheaper and safer to have a small, expert team develop some software that:
I know in my gut that the high level financial powers of the world know exactly what crypto currency is and they know the potential threat it is to their extremely lucrative scams (fiat currency, government enforced, crony banks). I know that if these people are willing to rob and scam almost every man, woman and child on the planet, in all cases resulting in reduced prosperity, in many cases resulting in poverty and in some cases even resulting in death, then these groups will almost certainly be comfortable funding operations to damage, delay and co-opt the cryptos that threaten their empires.
In this time of great technological advancement and mass social manipulation, I think it has become more important than ever to learn to think for yourself. There are pearls of wisdom and useful data out there, but to find them you have to learn to sift through a ton of shit. To do this effectively you need to develop discernment skills.
If you have personally concluded that a particular crypto is awesome (whether that be BCH, ETH or even BTC) and you notice large numbers of people telling you you're wrong, consider for a moment that those people might not be wise, might not be truthful and might not even be human. If they make good arguments, offer useful insights or provide verifiable data, then that may be something worth carefully considering. However, if they are just numerous, noisy and nasty, then I think it's quite reasonable to walk on by and confidently continue striding in the direction that you personally feel is best.
submitted by hapticpilot to btc [link] [comments]

Understanding Dxchain Network (Whitepaper Simplified SR -3)

Understanding Dxchain Network (Whitepaper Simplified SR -3)

https://preview.redd.it/8op68fnvcrr31.jpg?width=2485&format=pjpg&auto=webp&s=17636bbb43920630859717161ce3c743a3c596c0
For quick recap on what I covered in the past series:
  • What is Dxchain?
  • DxChain Architecture/Network Design Principle
  • Dxchain's Chains-on-chain structure
  • The General Communication Protocol
Previous articles are available here and here.
Today, I'll be covering basically "Dxchain's Storage And Data Model".

EFFICIENT STORAGE AND DATA MODEL (cloud computing).

Recently, Cloud computing has become a new trend of information technology and computing system. In the traditional computing infrastructure, operating system software, applications and data are typically stored and managed on an individual user’s computer. Cloud-computing has a different form from traditional way. All kinds of service and software are stored, accessed, and used via third party servers connected to the internet. If cloud computing was used, data and information can be easily shared and managed by user and service provider. Furthermore the user can do their works without application or software. When the user wants work using the software or application, the user just access cloud computing system via the internet. On the other hand, cloud computing has large data and information. Therefore the efficient method for large data/information management for cloud computing is necessary. In this paper, we proposed a cloud storage model for cloud computing environment. The model is to consider the relation between the cloud structures; service provider, application, and user.
Digging a bit deeper, let us take a glance at what storage model entails.
Storage model is a kind of miniature or a design that captures key physical aspects of data structure in a data store. It also captures key logical aspects of data structure in a database. The physical storage can be a local disk, a removable media, or storage accessible via the network.
With the help of decentralized storage network, the Dxchain Network is able to store files for computation results including all kinds of intermediate computation states.
The storage miners are intended to obtain incentives based on their continuous contributions to the storage chain. Apparently, the consensus-based protocols by Nakamoto, including PoW and PoS, do not fit this requirement. Proof of Spacetime (PoSt) is a good choice to validate the provision of storage. It has been discussed in Chapter Four that the DSC is designed to manage storage tasks and that DSC will also be connected to the master chain to obtain incentives for the storage miner as well as the CSC for storing computation states. Dxchain Network also for easy retrieval (flexibility) of files at a more granular(i,e small pieces) scale.
This brings us to the consensus protocol employed by Dxchain network proposed to achieve efficient storage system.

Consensus protocol

This is one of the most integral and vital aspect of a blockchain technology -one which is revolutionary in nature. This is a system of achieving an irrefutably an agreement between various devices across a distributed network, whilst in the process, preventing exploitation and bad actors from invading the system. To simply put: “A consensus protocol in a distributed system is a decision-making process by a predefined group in which members of the group develop, and agree to support a decision to the best interest of the whole members in the state of the network. It may also be defined professionally as an acceptable resolution, one that can be supported, even if not the “favorite” of each individual. Consensus is defined by Merriam-Webster as, first, general agreement, and second, group solidarity of belief or sentiment.”
Alternatively, it is a fault-tolerant mechanism that is used in computer and blockchain systems to achieve the necessary agreement on a single data value or a single state of the network among distributed processes or multi-agent systems, such as with cryptocurrencies. Some examples of consensus protocols includes:
  • Proof of work (POW) is a common consensus algorithm used by the most popular cryptocurrency networks like bitcoin and litecoin. POW as proved to be effective in installing security but for the few set back like high energy consumption and few others.
  • Proof of stake (POS) is another common consensus algorithm that evolved as a low-cost, low-energy consuming alternative to POW algorithm.
  • Proof of Capacity consensus mechanism uses a mining node’s hard drive space to decide the mining rights on the blockchain network, etc.
As an improvement over existing consensus algorithm -Provable Data Possession (PDP) which is described as being perfect fit for cloud computing storage, Dxchain Network designed an algorithm called Proof of Spacetime (PoSt) scheme , having an embedded zero-knowledge proof, to fit for a decentralized environment as such that it verifies whether or not a service provider actually store the data or not. The concept around this algorithm is proven to be resistible to Sybil, outsourcing and generation attacks.

Resources:
submitted by Bobelr to DxChainNetwork [link] [comments]

SegWit would make it HARDER FOR YOU TO PROVE YOU OWN YOUR BITCOINS. SegWit deletes the "chain of (cryptographic) signatures" - like MERS (Mortgage Electronic Registration Systems) deleted the "chain of (legal) title" for Mortgage-Backed Securities (MBS) in the foreclosure fraud / robo-signing fiasco

Summary (TL;DR)

Many people who study the financial crisis which started in 2008 know about "MERS", or "Mortgage Electronic Registration Systems" - a company / database containing over 62 million mortgages.
(The word "mortgages" may be unfamiliar to some non-English speakers - since it is not a cognate with most other languages. In French, they say "hypothèques", or "hipotecas" in Spanish, "Hypotheken" in German, etc).
The goal of MERS was to "optimize" the process of transferring "title" (legal ownership) of real-estate mortgages, from one owner to another.
But instead, in the 2010 "foreclosure crisis", MERS caused tens of billions of dollars in losses and damages - due to the "ususual" way it handled the crucial "ownership data" for real-estate mortgages - the data at the very heart of the database.
https://duckduckgo.com/?q=%22foreclosure+fraud%22+%22robo+signing%22+MERS&t=h_&ia=web
How did MERS handle this crucial "ownership data" for real-estate mortgages?
The "brilliant" idea behind MERS to "optimize" the process of conveying (transferring) mortgages was to separate - and eventually delete - all the data proving who transferred what to whom!
Hmm... that sounds vaguely familiar. What does that remind me of?
SegWit separating and then deleting the "chain of (cryptographic) signatures" for bitcoins sounds a lot like MERS separating and then deleting the "chain of (legal) title" for mortgages.
So, SegWit and MERS have a lot in common:
Of course, the "experts" (on Wall Street, and at AXA-owned Blockstream) present MERS and SegWit as "innovations" - as a way to "optimize" and "streamline" vast chains of transactions reflecting ownership and transfer of valuable items (ie, real-estate mortgages, and bitcoins).
But, unfortunately, the "brilliant bat-shit insane approach" devised by the "geniuses" behind MERS and SegWit to do this is to simply delete the data which proved ownership and transfer of these items - information which is essential for legal purposes (in the case of mortgages), or security purposes (in the case of bitcoins).
So, the most pernicious aspect of SegWit may be that it encourages deleting all of Bitcoin's cryptographic security data - destroying the "chain of signatures" which (according to the white paper) are what define what a "bitcoin" actually is.
Wow, deleting signatures with SegWit sounds bad. Can I avoid SegWit?
Yes you can.
To guarantee the long-term cryptographic, legal and financial security of your bitcoins:

Details

MERS = "The dog ate your mortgage's chain of title".
SegWit = "The dog ate your bitcoin's chain of signatures."
Wall Street-backed MERS = AXA-backed SegWit
It is probably no coincidence that:
How is AXA related to Blockstream?
Insurance multinational AXA, while not a household name, is actually the second-most-connected "fiat finance" firm in the world.
AXA's former CEO Pierre Castries was head of the secretive Bilderberg Group of the world's ultra-rich. (Recently, he moved on to HSBC.)
Due to AXA's massive exposure to derivatives (bigger than any other insurance company), it is reasonable to assume that AXA would be destroyed if Bitcoin reaches trillions of dollars in market cap as a major "counterparty-free" asset class - which would actually be quite easy using simple & safe on-chain scaling - ie, just using bigger blocks, and no SegWit.
So, the above facts provide one plausible explanation of why AXA-owned Blockstream seems to be quietly trying to undermine Bitcoin...
Do any Core / Blockstream devs and supporters know about MERS - and recognize its dangerous parallels with SegWit?
It would be interesting to hear from some of the "prominent" Core / Blockstream devs and supporters listed below to find out if they are aware of the dangerous similarities between SegWit and MERS:
Finally, it could also be interesting to hear from:
Core / Blockstream devs might not know about MERS - but AXA definitely does
While it is likely that most or all Core / Blockstream devs do not know about the MERS fiasco...
...it is 100% certain that people at AXA (the main owners of Blockstream) do know about MERS.
This is because the global financial crisis which started in 2008 was caused by:
The major financial media and blogs (Naked Capitalism, Zero Hedge, Credit Slips, Washington's Blog, etc.) covered MERS extensively:
https://duckduckgo.com/?q=site%3Anakedcapitalism.com+mers&t=h_&ia=web
https://duckduckgo.com/?q=site%3Azerohedge.com+mers&t=h_&ia=web
https://duckduckgo.com/?q=site%3Acreditslips.org+mers&t=h_&ia=web
https://duckduckgo.com/?q=site%3Awashingtonsblog.com+mers&t=h_&ia=web
So people at all the major "fiat finance firms" such as AXA would of course be aware of CDOs, MBSs and MERS - since these have been "hot topics" in their industry since the start of the global financial crisis in 2008.
Eerie parallels between MERS and SegWit
Read the analysis below of MERS by legal scholar Christopher Peterson - and see if you notice the eerie parallels with SegWit (with added emphasis in bold, and commentary in square brackets):
http://scholarship.law.wm.edu/cgi/viewcontent.cgi?article=3399&context=wmlr
Loans originated with MERS as the original mortgagee purport to separate the borrower’s promissory note, which is made payable to the originating lender, from the borrower’s conveyance of a mortgage, which purportedly is granted to MERS. If this separation is legally incorrect - as every state supreme court looking at the issue has agreed - then the security agreements do not name an actual mortgagee or beneficiary.
The mortgage industry, however, has premised its proxy recording strategy on this separation, despite the U.S. Supreme Court’s holding that “the note and mortgage are inseparable.” [Compare with the language from Satoshi's whitepaper: "We define an electronic coin as a chain of digital signatures."]
If today’s courts take the Carpenter decision at its word, then what do we make of a document purporting to create a mortgage entirely independent of an obligation to pay? If the Supreme Court is right that a “mortgage can have no separate existence” from a promissory note, then a security agreement that purports to grant a mortgage independent of the promissory note attempts to convey something that cannot exist.
[...]
Many courts have held that a document attempting to convey an interest in realty fails to convey that interest if the document does not name an eligible grantee. Courts around the country have long held that “there must be, in every grant, a grantor, a grantee and a thing granted, and a deed wanting in either essential is absolutely void.”
The parallels between MERS and SegWit are obvious and inescapable.
Note that I am not arguing here that SegWit could be vulnerable to attacks from a strictly legal perspective. (Although that may be possible to.)
I am simply arguing that SegWit, because it encourages deleting the (cryptographic) signature data which defines "bitcoins", could eventually be vulnerable to attacks from a cryptographic perspective.
But I heard that SegWit is safe and tested!
Yeah, we've heard a lot of lies from Blockstream, for years - and meanwhile, they've only succeeded in destroying Bitcoin's market cap, due to unnecessarily high fees and unnecessarily slow transactions.
Now, in response to those legal-based criticisms of SegWit in the article from nChain, several so-called "Bitcoin legal experts" have tried to rebut that those arguments from nChain were somehow "flawed".
But if you read the rebuttals of these "Bitcoin legal experts", they sound a lot like the clueless "experts" who were cheerleading MERS for its "efficiency" - and who ended up costing tens billions of dollars in losses when the "chain of title" for mortgages held in the MERS database became "clouded" after all the crucial "ownership data" got deleted in the name of "efficiency" and "optimization".
In their attempt to rebut the article by nChain, these so-called "Bitcoin legal experts" use soothing language like "optimization" and "pragmatic" to try to lull you into believing that deleting the "chain of (cryptographic) signatures" for your bitcoins will be just as safe as deleting the "chain of (legal) notes" for mortgages:
http://www.coindesk.com/bitcoin-legal-experts-nchain-segwit-criticisms-flawed/
The (unsigned!) article on CoinDesk attempting to rebut Nguyen's article on nChain starts by stating:
Nguyen's criticisms fly in the face of what has emerged as broad support for the network optimization, which has been largely embraced by the network's developers, miners and startups as a pragmatic step forward.
Then it goes on to quote "Bitcoin legal experts" who claim that using SegWit to delete Bitcoin's cryptographic signatures will be just fine:
Marco Santori, a fintech lawyer who leads the blockchain tech team at Cooley LLP, for example, took issue with what he argued was the confused framing of the allegation.
Santori told CoinDesk:
"It took the concept of what is a legal contract, and took the position that if you have a blockchain signature it has something to do with a legal contract."
And:
Stephen Palley, counsel at Washington, DC, law firm Anderson Kill, remarked similarly that the argument perhaps put too much weight on the idea that the "signatures" involved in executing transactions on the bitcoin blockchain were or should be equivalent to signatures used in digital documents.
"It elides the distinction between signature and witness data and a digital signature, and they're two different things," Palley said.
And:
"There are other ways to cryptographically prove a transaction is correctly signed other than having a full node," said BitGo engineer Jameson Lopp. "The assumption that if a transaction is in the blockchain, it's probably valid, is a fairly good guarantee."
Legal experts asserted that, because of this design, it's possible to prove that the transaction occurred between parties, even if those involved did not store signatures.
For this reason, Coin Center director Jerry Brito argued that nChain is overstating the issues that would arise from the absence of this data.
"If you have one-time proof that you have the bitcoin, if you don't have it and I have it, logically it was signed over to me. As long as somebody in the world keeps the signature data and it's accessible, it's fine," he said.
There are several things you can notice here:
  • These so-called "Bitcoin legal experts" are downplaying the importance of signatures in Bitcoin - just like the "experts" behind MERS downplayed the importance of "notes" for mortgages.
  • Satoshi said that a bitcoin is a "chain of digital signatures" - but these "Bitcoin legal experts" are now blithely asserting that we can simply throw the "chain of digital signatures" in the trash - and we can be "fairly" certain that everything will "probably" be ok.
  • The "MERS = SegWit" argument which I'm making is not based on interpreting Bitcoin signatures in any legal sense (although some arguments could be made along those lines).
  • Instead, I'm just arguing that any "ownership database" which deletes its "ownership data" (whether it's MERS or SegWit) is doomed to end in disaster - whether that segregated-and-eventually-deleted "ownership data" is based on law (with MERS), or cryptography (with SegWit).
Who's right - Satoshi or the new "Bitcoin experts"?
You can make up your own mind.
Personally, I will never send / receive / store large sums of money using any "SegWit" bitcoin addresses.
This, is not because of any legal considerations - but simply because I want the full security of "the chain of (cryptographic) signatures" - which, according to the whitepaper, is the very definition of what a bitcoin "is".
Here are the words of Satoshi, from the whitepaper, regarding the "chain of digital signatures":
https://www.bitcoin.com/bitcoin.pdf
We define an electronic coin as a chain of digital signatures. Each owner transfers the coin to the next by digitally signing a hash of the previous transaction and the public key of the next owner and adding these to the end of the coin. A payee can verify the signatures to verify the chain of ownership.
Does that "chain of digital signatures" sound like something you'd want to throw in the trash??
  • The "clever devs" from AXA-owned Blockstream (and a handful of so-called "Bitcoin legal experts) say "Trust us, it is safe to delete the chain of signatures proving ownership and transfer of bitcoins". They're pushing "SegWit" - the most radical change in the history of Bitcoin. As I have repeatedly discussed, SegWit weakens Bitcoin's security model.
  • The people who support Satoshi's original Bitcoin (and clients which continue to implement it: Bitcoin ABC, Bitcoin Unlimited, Bitcoin, Bitcoin Classic - all supporting "Bitcoin Cash" - ie "Bitcoin" without SegWit) say "Trust no one. You should never delete the chain of signatures proving ownership and transfer of your bitcoins."
  • Satoshi said:

We define an electronic coin as a chain of digital signatures.

  • So, according to Satoshi, a "chain of digital signatures" is the very definition of what a bitcoin is.
  • Meanwhile according to some ignorant / corrupt devs from AXA-owned Blockstream (and a handful of "Bitcoin legal experts") now suddenly it's "probably" "fairly" safe to just throw Satoshi's "chain of digital signatures" in the trash - all in the name of "innovation" and "efficiency" and "optimization" - because they're so very clever.
Who do you think is right?
Finally, here's another blatant lie from SegWit supporters (and small-block supporters)
Let's consider this other important quote from Satoshi's whitepaper above:
A payee can verify the signatures to verify the chain of ownership.
Remember, this is what "small blockers" have always been insisting for years.
They've constantly been saying that "blocks need to be 1 MB!!1 Waah!1!" - even though several years ago the Cornell study showed that blocks could already be 4 MB, with existing hardware and bandwidth.
But small-blockers have always insisted that everyone should store the entire blockchain - so they can verify their own transactions.
But hey, wait a minute!
Now they turn around and try to get you to use SegWit - which allows deleting the very data which insisted that you should download and save locally to verify your own transactions!
So, once again, this exposes the so-called "arguments" of small-blocks supporters as being fake arguments and lies:
  • On the one hand, they (falsely) claim that small blocks are necessary in order for everyone to be run "full nodes" because (they claim) that's the only way people can personally verify all their own transactions. By the way, there are already several errors here with what they're saying:
    • Actually "full nodes" is a misnomer (Blockstream propaganda). The correct terminology is "full wallets", because only miners are actually "nodes".
    • Actually 1 MB "max blocksize" is not necessary for this. The Cornell study showed that we could easily be using 4 MB or 8 MB blocks by now - since, as everyone knows, the average size of most web pages is already over 2 MB, and everyone routinely downloads 2 MB web pages in a matter of seconds, so in 10 minutes you could download - and upload - a lot more than just 2 MB. But whatever.
  • On the other hand, they support SegWit - and the purpose of SegWit is to allow people to delete the "signature data".
    • This conflicts with their argument the everyone should personally verify all their own transactions. For example, above, Coin Center director Jerry Brito was saying: "As long as somebody in the world keeps the signature data and it's accessible, it's fine."
    • So which is it? For years, the "small blockers" told us we needed to all be able to personally verify everything on our own node. And now SegWit supporters are telling us: "Naah - you can just rely on someone else's node."
    • Plus, while the transactions are still being sent around on the wire, the "signature data" is still there - it's just "segregated" - so you're not getting any savings on bandwidth anyways - you'd only get the savings if you delete the "signature data" from storage.
    • Storage is cheap and plentiful, it's never been the "bottleneck" in the system. Bandwidth is the main bottleneck - and SegWit doesn't help that at all, because it still transmits all the data.
Conclusion
So if you're confused by all the arguments from small-blockers and SegWitters, there's a good reason: their "arguments" are total bullshit and lies. They're attempting to contradict and destroy:
  • Satoshi's original design of Bitcoin as a "chain of digital signatures":
"We define an electronic coin as a chain of digital signatures. Each owner transfers the coin to the next by digitally signing a hash of the previous transaction and the public key of the next owner and adding these to the end of the coin. A payee can verify the signatures to verify the chain of ownership."
  • Satoshi's plan for scaling Bitcoin by simply increasing the goddamn blocksize:
Satoshi Nakamoto, October 04, 2010, 07:48:40 PM "It can be phased in, like: if (blocknumber > 115000) maxblocksize = largerlimit / It can start being in versions way ahead, so by the time it reaches that block number and goes into effect, the older versions that don't have it are already obsolete."
https://np.reddit.com/btc/comments/3wo9pb/satoshi_nakamoto_october_04_2010_074840_pm_it_can/
  • The the notorious mortgage database MERS, pushed by clueless and corrupt Wall Street bankers, deleted the "chain of (legal) title" which had been essential to show who conveyed what mortgages to whom - leading to "clouded titles", foreclosure fraud, and robo-signing.
  • The notorious SegWit soft fork / kludge, pushed by clueless and corrupt AXA-owned Blockstream devs, allows deleting the "chain of (cryptographic) signatures" which is essential to show who sent how many bitcoins to whom - which could lead to a catastrophe for people who foolishly use SegWit addresses (which can be avoided: unsafe "SegWit" bitcoin addresses start with a "3" - while safe, "normal" Bitcoin addresses start with a "1").
  • Stay safe and protect your bitcoin investment: Avoid SegWit transactions.
[See the comments from me directly below for links to several articles on MERS, foreclosure fraud, robo-signing, "clouded title", etc.]
submitted by ydtm to btc [link] [comments]

PSA: User-activated soft fork proposal does not involve counting nodes or any other sybil-able metric

I've seen a misunderstanding floating around that I wanted to correct.
Many people think the User-Activated Soft Fork (UASF) proposal involves counting nodes out there on the p2p network. They rightly say this would be open to sybil attacks and therefore is unsafe.
That is incorrect. UASF does not rely on counting nodes or any other sybil-able metric. Take the example of the full node belonging to BitGo. They provide wallet services to big exchanges like Kraken and Bitstamp. Their full node wallet is far more important to the economic majority than some node doing nothing running on rented hardware. BitGo's full node probably isn't even visible on the network for security reasons. So it would be really dumb to rely on p2p node counting, which is why nobody has even suggested it.
The real way we can figure out what the economic majority wants is simply by asking them. There is already this page (https://bitcoincore.org/en/segwit_adoption/) which lists more than 100 projects and businesses that are ready and willing for the BIP9 segwit soft fork. They include names like localbitcoins, coinbase.com and the already-mentioned BitGo, they form a huge part of the economic majority. After the technical details of UASF are discussed more, probably what will happen these busnesses will simply be asked whether they are willing to enforce the UASF for segwit, and if so, a new version of the full node software can be released.
Note that businesses are being hit by the recent rise in miner fees. Projects generally receive lots of small payments which requires large and expensive transactions to combine together, so they pay more in miner fees proportionally than individual users. So businesses have a strong incentive to increase efficiency somehow, hard forking is too unsafe so the only thing available right now is segwit.
submitted by belcher_ to Bitcoin [link] [comments]

Core is proposing a sybil attack? or not? How is this defended by the implementation devs?

Someone linked me to some /bitcoin conversations where devs are suggesting using node count to activate segwit (node-activated soft fork) because the 95% hash rate activation will never happen. I have some questions about that:
  1. How is this not a sybil attack? It would use node count to kick all nodes and miners off the network that doesn't follow the attacking node-cluster's rules.
  2. Has node count ever been used for anything? From the bitcoin wiki (which i believe is core-maintained?): "Bitcoin never uses a count of nodes for anything"
  3. How does correspond with the Core position that "all changes must have unanimous consensus" or "all changes must have 95% consensus", or else they are "dangerous", and dangerous forks are unacceptable? They seem to be mutually exclusive positions.
  4. How does this correspond with the Core position that node count doesn't matter? When BU first started spinning up and nodes were on the network and before it took on hashrate, core devs said, "nodes mean nothing as anyone can easily spool up as many nodes as they want to inflate the BU numbers, they're not real." Obviously that argument went away once miners started mining BU, but the point on spinning up nodes remains. How can they say both node count is meaningless and should be used to activate a fork?
  5. Similar to 4, why is they calling it a "user-activated soft-fork"? Isn't it nodes, not users?
submitted by jeanduluoz to btc [link] [comments]

An Analysis of Attacks on Blockchain Consensus

arXiv:1610.07985
Date: 2016-11-20
Author(s): George Bissias, Brian Neil Levine, A. Pinar Ozisik, Gavin Andresen

Link to Paper


Abstract
We present and validate a novel mathematical model of the blockchain mining process and use it to conduct an economic evaluation of the double-spend attack, which is fundamental to all blockchain systems. Our analysis focuses on the value of transactions that can be secured under a conventional double-spend attack, both with and without a concurrent eclipse attack. Our model quantifies the importance of several factors that determine the attack's success, including confirmation depth, attacker mining power, and any confirmation deadline set by the merchant. In general, the security of a transaction against a double-spend attack increases roughly logarithmically with the depth of the block, made easier by the increasing sum of coin turned-over (between individuals) in the blocks, but more difficult by the increasing proof of work required. In recent blockchain data, we observed a median block turnover value of 6 BTC. Based on this value, a merchant requiring a single confirmation is protected against only attackers that can increase the current mining power by 1% or less. However, similar analysis shows that a merchant that requires a much longer 72 confirmations (~12 hours) will eliminate all potential profit for any double-spend attacker adding mining power less than 40% of the current mining power.

References
  1. Back, A., Corallo, M., Dashjr, L., Mark, F., Maxwell, G., Miller, A., Poelstra, A., Timón, J., Wuille, P.: Enabling Blockchain Innovations with Pegged Sidechains. http://www.opensciencereview.com/papers/123/enablingblockchain-innovations-with-pegged-sidechains (October 2014)
  2. Bissias, G., Ozisik, A.P., Levine, B.N., Liberatore, M.: Sybil-Resistant Mixing for Bitcoin. In: Proc. ACM Workshop on Privacy in the Electronic Society (November 2014), http://forensics.umass.edu/pubs/bissias.wpes.2014.pdf
  3. Confirmation. https://en.bitcoin.it/wiki/Confirmation (February 2015)
  4. Bonneau, J., Miller, A., Clark, J., Narayanan, A., Kroll, J., Felten, E.: Sok: Research perspectives and challenges for bitcoin and cryptocurrencies. In: IEEE S&P. pp. 104–121 (May 2015), http://doi.org/10.1109/SP.2015.14
  5. Bonneau, J.: How long does it take for a bitcoin transaction to be confirmed? https://coincenter.org/2015/11/what-does-it-mean-for-a-bitcoin-transactionto-be-confirmed/ (November 2015)
  6. Croman, K., et al.: On Scaling Decentralized Blockchains . In: Workshop on Bitcoin and Blockchain Research (Feb 2016)
  7. Douceur, J.: The Sybil Attack. In: Proc. Intl Wkshp on Peer-to-Peer Systems (IPTPS) (Mar 2002)
  8. Ethereum Homestead Documentation. http://ethdocs.org/en/latest/
  9. Eyal, I., Sirer, E.G.: Majority Is Not Enough: Bitcoin Mining Is Vulnerable. Financial Cryptography pp. 436–454 (2014), http://doi.org/10.1007/978-3-662-45472-5_28
  10. Fischer, M., Lynch, N., Paterson, M.: Impossibility of distributed consensus with one faulty process. JACM 32(2), 374–382 (1985)
  11. Gervais, A., O. Karame, G., Wust, K., Glykantzis, V., Ritzdorf, H., Capkun, S.: On the Security and Performance of Proof of Work Blockchains. https://eprint.iacr.org/2016/555 (2016)
  12. Heilman, E., Alshenibr, L., Baldimtsi, F., Scafuro, A., Goldberg, S.: Tumblebit: An untrusted bitcoin-compatible anonymous payment hub. Cryptology ePrint Archive, Report 2016/575 (2016), http://eprint.iacr.org/2016/575
  13. Heilman, E., Kendler, A., Zohar, A., Goldberg, S.: Eclipse Attacks on Bitcoin’s Peer-to-peer Network. In: USENIX Security (2015)
  14. Litecoin. http://litecoin.org/
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  16. Nakamoto, S.: Bitcoin: A Peer-to-Peer Electronic Cash System. https://bitcoin.org/bitcoin.pdf (May 2009)
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  18. Poon, J., Dryja, T.: The Bitcoin Lightning Network: Scalable Off-Chain Instant Payments. http://www.lightning.network/lightning-network-paper.pdf (November 2015)
  19. Ron, D., Shamir, A.: Quantitative analysis of the full bitcoin transaction graph. In: Proc. Financial Crypto. pp. 6–24 (Apr 2013), http://doi.org/10.1007/978-3-642-39884-1_2
  20. Rosenfeld, M.: Analysis of hashrate-based double-spending. https://bitcoil.co.il/Doublespend.pdf (December 2012)
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What Is Bytom (BTM)?

What Is Bytom (BTM)?
The world today has been massively influenced by the information revolution of the last few years. More and more elements of the physical world are getting transmitted into the digital world. With the rising relevance of big data, computing power plays a more central role in technological advancement.
First came the tools that allowed us to work via digital platforms, such as email and software. Then came currencies that allowed peer-to-peer transfer of value over the digital world, such as Bitcoin. The next phase in consideration is a system where every valuable thing (that can be exchanged) is migrated to the digital world. Examples of things like that include equities, securitized assets, dividends, bonds, and so on.
Bytom is a protocol and a blockchain for the exchange and interaction of real-world assets. Bytom is different from Ethereum, as it focuses on putting real-world assets on its blockchain.
Specifically, Bytom focuses on avoiding the replication of real-world assets on the blockchain, resolving compliance issues as digital assets are linked to physical assets, and bridging the gap between the physical world and the digital world.

What Does Bytom Do?

Bytom is basically a digital asset layer protocol. It enables individuals and institutions to build financial and digital asset applications. Stocks, bonds, and any kind of secure data can also be exchanged on the blockchain.
Bytom aims to map assets in the physical world to the digital world and create an ecosystem where there is interoperability between these 2 forms.
There are 3 types of assets on the Bytom blockchain that can be exchanged:
  • Income assets, which include non-performing assets, fixed local government investments, home-stay properties, etc.
  • Equity assets, which include equity of non-listed companies, equity of private funds, etc. Transferring equity assets requires qualified investor verification.
  • Securitized assets, which includes debts, automobile loans, etc. Generally, these are assets that can generate predictable cash flows.
These assets are tradable on-chain with the Bytom protocol. Bytom cuts out the middlemen in asset transfers and recordkeeping, which leads to faster transactions and lower costs. Also, the assets are more secure on a blockchain than with a third-party organization.
Users can create their asset-backed security on the Bytom blockchain by registering and tokenizing their assets via smart contract. Bytom can also function as a platform for fundraising or ICOs.

Bytom’s Consensus Model

Bytom uses a Proof-of-Work consensus model, the mechanism currently used by Bitcoin and Ethereum. It is important that the blockchain is not vulnerable to the Sybil attack and the 51% attack. This is because Bytom deals with assets. To be realistic with the demands of the blockchain system, it prioritizes decentralization and security over performance.
Bytom’s consensus mechanism is designed to be “friendly to AI ASIC chips,” as described in the whitepaper. This means that the miners can be used for AI hardware acceleration services. Bytom implements cross-chain asset transactions and dividend distribution via side-chain. It also has a quasi SegWit design.

History of Bytom

Started in January 2017, Bytom was founded by Chang Jia (former sci-fi writer and creator of 8btc) and Duan Xinxing (former Vice President of OKCoin).
The Bytom token sale took place from June 20 to July 20, 2017, and raised 8,400 Bitcoins. 30% of the total supply was distributed during ICO. 20% was reserved for the Bytom Foundation, 7% for private equity investors, 10% for business development, and 33% for mining.

The Bytom Team

The Bytom team is headed by its founders, Chang Jia, and Duan Xinxing. Duan functions as the CEO of Bytom. The CTO is Lang Yu (former senior systems engineer for Alipay). The COO is Qu Zhaoxiang and the CFO, Li Zongcheng.
The team further consists of developers and managers committed to the mission of Bytom.
The Bytom Foundation is based in Singapore, where the government favors blockchain developments and the environment enables growth in the ecosystem.

Bytom Roadmap and Achievements

The Bytom mainnet was officially launched on April 24, 2018. The token swap of the ERC-20 Bytom tokens for the native Bytom coins took place in June 2018 across several exchanges.
As indicated on their roadmap, Bytom then released smart contract functionality on their platform on July 26, 2018. Their roadmap can be seen below.
roadmap
Bytom is taking steps to bring its vision to life through partnerships.
A notable partnership so far is with East Lake Big Data Asset Exchange, an organization committed to providing big data solutions for Chinese government agencies. The organization collaborates with Bytom in the area of blockchain innovation and data assets trading.

The Bytom Token (BTM)

The Bytom blockchain has a native token known as BTM. The main uses of BTM are as a transaction fee for asset trading, dividends for income assets, and deposits for asset issuance.
The maximum number of Bytom tokens is 2.1 billion. Currently, over 1 billion BTM coins are already in circulation. The current price of Bytom is close to US$0.20.
Bytom coins can be bought with other cryptocurrencies on several exchanges, such as RightBTC, Huobi, OKEx, KuCoin, and Bibox.
BTM coins can be stored in Bytom’s official wallet. This wallet is available for download on Windows, Linux, and macOS.

Conclusion

Bytom creates the opportunity to move real-world assets into the digital world. This interoperability will open both blockchain and the tech world as a whole to more innovative ideas that will move civilization forward.
One standout feature of Bytom is that the team has hit the milestones set out on their roadmap.
The problem Bytom seeks to solve will be a necessity in a few years, if the world continues with this heavy trend of decentralization. However, it is still too early to determine how successful Bytom is going to be.
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Bobtail: A Proof-of-Work Target that Minimizes Blockchain Mining Variance

arXiv:1709.08750
Date: 2017-10-19
Author(s): George Bissias, Brian Neil Levine

Link to Paper


Abstract
Blockchain systems are designed to produce blocks at a constant average rate. The most popular systems currently employ a Proof of Work (PoW) algorithm as a means of creating these blocks. Bitcoin produces, on average, one block every 10 minutes. An unfortunate limitation of all deployed PoW blockchain systems is that the time between blocks has high variance. For example, 5% of the time, Bitcoin's inter-block time is at least 40 minutes. This variance impedes the consistent flow of validated transactions through the system. We propose an alternative process for PoW-based block discovery that results in an inter-block time with significantly lower variance. Our algorithm, called Bobtail, generalizes the current algorithm by comparing the mean of the k lowest order statistics to a target. We show that the variance of inter-block times decreases as k increases. If our approach were applied to Bitcoin, about 80% of blocks would be found within 7 to 12 minutes, and nearly every block would be found within 5 to 18 minutes; the average inter-block time would remain at 10 minutes. Further, we show that low-variance mining significantly thwarts doublespend and selfish mining attacks. For Bitcoin and Ethereum currently (k=1), an attacker with 40% of the mining power will succeed with 30% probability when the merchant sets up an embargo of 8 blocks; however, when k>=20, the probability of success falls to less than 1%. Similarly, for Bitcoin and Ethereum currently, a selfish miner with 40% of the mining power will claim about 66% of blocks; however, when k>=5, the same miner will find that selfish mining is less successful than honest mining. The cost of our approach is a larger block header.

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Estimation of Miner Hash Rates and Consensus on Blockchains

arXiv:1707.00082
Date: 2017-07-01
Author(s): A. Pinar Ozisik, George Bissias, Brian Levine

Link to Paper


Abstract
We make several contributions that quantify the real-time hash rate and therefore the consensus of a blockchain. We show that by using only the hash value of blocks, we can estimate and measure the hash rate of all miners or individual miners, with quanti able accuracy. We apply our techniques to the Ethereum and Bitcoin blockchains; our solution applies to any proof-of-work-based blockchain that relies on a numeric target for the validation of blocks. We also show that if miners regularly broadcast status reports of their partial proof-of- work, the hash rate estimates are signi cantly more accurate at a cost of slightly higher bandwidth. Whether using only the blockchain, or the additional information in status reports, merchants can use our techniques to quantify in real-time the threat of double-spend attacks.

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Why Dash is the Most Sybil Attack-Resistant Cryptocurrency -- By Far EB70 – Chainalysis, Surveillance And The Path To Mass Panic What is a 51% Attack - Bitcoin Tutorial Sybil Attacks - Blockchain Security Cerys Bradley asks

A Sybil attack is an attack where a single adversary is controlling multiple nodes on a network. It is unknown to the network that the nodes are controlled by the same adversarial entity. For example, an adversary can spawn up multiple computers, virtual machines, and IP addresses. In this paper, we describe the weaknesses of extant mixing protocols, and analyze their vulnerability to Sybil-based denial-of-service and inference attacks. As a solution, we propose Xim, a two-party mixing protocol that is compatible with Bitcoin and related virtual currencies. Bitcoin has some security issues as it is potentially vulnerable to certain types of attacks: Sybil attack, 51% attack, DoS and others. In the article there is a review of the main disadvantages of Bitcoin cryptocurrency. Like other proof-of-work blockchains, Bitcoin can technically suffer a 51% attack. However, strength of the bitcoin network comes from its substantial mining hash power, which is currently 42.8 EHash per second [6], or 428,000,000,000,000,000,000 H/s. In Bitcoin Wiki Weaknesses: Sybil attack they mention that: "Bitcoin makes these attacks more difficult by only making an outbound connection to one IP address per /16 (x.y.0.0)". Why would this network connection sybil-attack

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Why Dash is the Most Sybil Attack-Resistant Cryptocurrency -- By Far

Do you REALLY understand Bitcoin 51% Attack? Programmer explains. - Duration: 11:28. Ivan on Tech 80,336 views. 11:28. How Bitcoin Works Under the Hood - Duration: 22:25. In this video I make some calculations about the costs of making a sybil attack on the Bitcoin network. If this video helped you and you'd like to give back you can send bitcoin to this address ... Sybil Attack in Online Social Networks. Sybil Attack in Online Social Networks. ... The costs of HACKING BITCOIN - Sybil Attacks Explained - Duration: 20:09. CryptoClarity 2,207 views. Cerys is a PhD student in the department of Crime and Security Science, UCL. She's also a member of the Showoff Talent Factory, an emerging group of science performers supported by Steve Cross ... - What damage a large scale sybil attack could really do to Bitcoin - The role transaction monitoring will play to achieve Bitcoin integration in existing systems

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