submitted by j0j0r0 to ethereum [link] [comments]
Dragonchain Public Proposal TL;DR:Dragonchain has demonstrated twice Reddit’s entire total daily volume (votes, comments, and posts per Reddit 2019 Year in Review) in a 24-hour demo on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. At the time, in January 2020, the entire cost of the demo was approximately $25K on a single system (transaction fees locked at $0.0001/txn). With current fees (lowest fee $0.0000025/txn), this would cost as little as $625.
Watch Joe walk through the entire proposal and answer questions on YouTube.
This proposal is also available on the Dragonchain blog.
Hello Reddit and Ethereum community!I’m Joe Roets, Founder & CEO of Dragonchain. When the team and I first heard about The Great Reddit Scaling Bake-Off we were intrigued. We believe we have the solutions Reddit seeks for its community points system and we have them at scale.
For your consideration, we have submitted our proposal below. The team at Dragonchain and I welcome and look forward to your technical questions, philosophical feedback, and fair criticism, to build a scaling solution for Reddit that will empower its users. Because our architecture is unlike other blockchain platforms out there today, we expect to receive many questions while people try to grasp our project. I will answer all questions here in this thread on Reddit, and I've answered some questions in the stream on YouTube.
We have seen good discussions so far in the competition. We hope that Reddit’s scaling solution will emerge from The Great Reddit Scaling Bake-Off and that Reddit will have great success with the implementation.
Executive summaryDragonchain is a robust open source hybrid blockchain platform that has proven to withstand the passing of time since our inception in 2014. We have continued to evolve to harness the scalability of private nodes, yet take full advantage of the security of public decentralized networks, like Ethereum. We have a live, operational, and fully functional Interchain network integrating Bitcoin, Ethereum, Ethereum Classic, and ~700 independent Dragonchain nodes. Every transaction is secured to Ethereum, Bitcoin, and Ethereum Classic. Transactions are immediately usable on chain, and the first decentralization is seen within 20 seconds on Dragon Net. Security increases further to public networks ETH, BTC, and ETC within 10 minutes to 2 hours. Smart contracts can be written in any executable language, offering full freedom to existing developers. We invite any developer to watch the demo, play with our SDK’s, review open source code, and to help us move forward. Dragonchain specializes in scalable loyalty & rewards solutions and has built a decentralized social network on chain, with very affordable transaction costs. This experience can be combined with the insights Reddit and the Ethereum community have gained in the past couple of months to roll out the solution at a rapid pace.
Response and PoCIn The Great Reddit Scaling Bake-Off post, Reddit has asked for a series of demonstrations, requirements, and other considerations. In this section, we will attempt to answer all of these requests.
A live proof of concept showing hundreds of thousands of transactionsOn Jan 7, 2020, Dragonchain hosted a 24-hour live demonstration during which a quarter of a billion (250 million+) transactions executed fully on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. This means that every single transaction is secured by, and traceable to these networks. An attack on this system would require a simultaneous attack on all of the Interchained networks.
24 hours in 4 minutes (YouTube):
24 hours in 4 minutes
The demonstration was of a single business system, and any user is able to scale this further, by running multiple systems simultaneously. Our goals for the event were to demonstrate a consistent capacity greater than that of Visa over an extended time period.
Tooling to reproduce our demo is available here:
Source code (for on & off-chain components as well tooling used for the PoC). The source code does not have to be shared publicly, but if Reddit decides to use a particular solution it will need to be shared with Reddit at some point.
How it works & scales
Architectural ScalingDragonchain’s architecture attacks the scalability issue from multiple angles. Dragonchain is a hybrid blockchain platform, wherein every transaction is protected on a business node to the requirements of that business or purpose. A business node may be held completely private or may be exposed or replicated to any level of exposure desired.
Every node has its own blockchain and is independently scalable. Dragonchain established Context Based Verification as its consensus model. Every transaction is immediately usable on a trust basis, and in time is provable to an increasing level of decentralized consensus. A transaction will have a level of decentralization to independently owned and deployed Dragonchain nodes (~700 nodes) within seconds, and full decentralization to BTC and ETH within minutes or hours. Level 5 nodes (Interchain nodes) function to secure all transactions to public or otherwise external chains such as Bitcoin and Ethereum. These nodes scale the system by aggregating multiple blocks into a single Interchain transaction on a cadence. This timing is configurable based upon average fees for each respective chain. For detailed information about Dragonchain’s architecture, and Context Based Verification, please refer to the Dragonchain Architecture Document.
Economic ScalingAn interesting feature of Dragonchain’s network consensus is its economics and scarcity model. Since Dragon Net nodes (L2-L4) are independent staking nodes, deployment to cloud platforms would allow any of these nodes to scale to take on a large percentage of the verification work. This is great for scalability, but not good for the economy, because there is no scarcity, and pricing would develop a downward spiral and result in fewer verification nodes. For this reason, Dragonchain uses TIME as scarcity.
TIME is calculated as the number of Dragons held, multiplied by the number of days held. TIME influences the user’s access to features within the Dragonchain ecosystem. It takes into account both the Dragon balance and length of time each Dragon is held. TIME is staked by users against every verification node and dictates how much of the transaction fees are awarded to each participating node for every block.
TIME also dictates the transaction fee itself for the business node. TIME is staked against a business node to set a deterministic transaction fee level (see transaction fee table below in Cost section). This is very interesting in a discussion about scaling because it guarantees independence for business implementation. No matter how much traffic appears on the entire network, a business is guaranteed to not see an increased transaction fee rate.
Scaled DeploymentDragonchain uses Docker and Kubernetes to allow the use of best practices traditional system scaling. Dragonchain offers managed nodes with an easy to use web based console interface. The user may also deploy a Dragonchain node within their own datacenter or favorite cloud platform. Users have deployed Dragonchain nodes on-prem on Amazon AWS, Google Cloud, MS Azure, and other hosting platforms around the world. Any executable code, anything you can write, can be written into a smart contract. This flexibility is what allows us to say that developers with no blockchain experience can use any code language to access the benefits of blockchain. Customers have used NodeJS, Python, Java, and even BASH shell script to write smart contracts on Dragonchain.
With Docker containers, we achieve better separation of concerns, faster deployment, higher reliability, and lower response times.
We chose Kubernetes for its self-healing features, ability to run multiple services on one server, and its large and thriving development community. It is resilient, scalable, and automated. OpenFaaS allows us to package smart contracts as Docker images for easy deployment.
Contract deployment time is now bounded only by the size of the Docker image being deployed but remains fast even for reasonably large images. We also take advantage of Docker’s flexibility and its ability to support any language that can run on x86 architecture. Any image, public or private, can be run as a smart contract using Dragonchain.
Flexibility in ScalingDragonchain’s architecture considers interoperability and integration as key features. From inception, we had a goal to increase adoption via integration with real business use cases and traditional systems.
We envision the ability for Reddit, in the future, to be able to integrate alternate content storage platforms or other financial services along with the token.
Cost estimates (on-chain and off-chain) For the purpose of this proposal, we assume that all transactions are on chain (posts, replies, and votes).On the Dragonchain network, transaction costs are deterministic/predictable. By staking TIME on the business node (as described above) Reddit can reduce transaction costs to as low as $0.0000025 per transaction.
Dragonchain Fees Table
How to run itBuilding on Dragonchain is simple and requires no blockchain experience. Spin up a business node (L1) in our managed environment (AWS), run it in your own cloud environment, or on-prem in your own datacenter. Clear documentation will walk you through the steps of spinning up your first Dragonchain Level 1 Business node.
Getting started is easy...
ArchitectureDragonchain is an open source hybrid platform. Through Dragon Net, each chain combines the power of a public blockchain (like Ethereum) with the privacy of a private blockchain.
Dragonchain organizes its network into five separate levels. A Level 1, or business node, is a totally private blockchain only accessible through the use of public/private keypairs. All business logic, including smart contracts, can be executed on this node directly and added to the chain.
After creating a block, the Level 1 business node broadcasts a version stripped of sensitive private data to Dragon Net. Three Level 2 Validating nodes validate the transaction based on guidelines determined from the business. A Level 3 Diversity node checks that the level 2 nodes are from a diverse array of locations. A Level 4 Notary node, hosted by a KYC partner, then signs the validation record received from the Level 3 node. The transaction hash is ledgered to the Level 5 public chain to take advantage of the hash power of massive public networks.
Dragon Net can be thought of as a “blockchain of blockchains”, where every level is a complete private blockchain. Because an L1 can send to multiple nodes on a single level, proof of existence is distributed among many places in the network. Eventually, proof of existence reaches level 5 and is published on a public network.
APIs (on chain & off)
Known issues or tradeoffs
Costs and resources
Summary of cost & resource information for both on-chain & off-chain components used in the PoC, as well as cost & resource estimates for further scaling. If your PoC is not on mainnet, make note of any mainnet caveats (such as congestion issues).Every transaction on the PoC system had a transaction fee of $0.0001 (one-hundredth of a cent USD). At 256MM transactions, the demo cost $25,600. With current operational fees, the same demonstration would cost $640 USD.
For the demonstration, to achieve throughput to mimic a worldwide payments network, we modeled several clients in AWS and 4-5 business nodes to handle the traffic. The business nodes were tuned to handle higher throughput by adjusting memory and machine footprint on AWS. This flexibility is valuable to implementing a system such as envisioned by Reddit. Given that Reddit’s daily traffic (posts, replies, and votes) is less than half that of our demo, we would expect that the entire Reddit system could be handled on 2-5 business nodes using right-sized containers on AWS or similar environments.
Verification was accomplished on the operational Dragon Net network with over 700 independently owned verification nodes running around the world at no cost to the business other than paid transaction fees.
This PoC should scale to the numbers below with minimal costs (both on & off-chain). There should also be a clear path to supporting hundreds of millions of users.During Dragonchain’s 24 hour demo, the above required numbers were reached within the first few minutes.
Reddit’s total activity is 9000% more than Ethereum’s total transaction level. Even if you do not include votes, it is still 700% more than Ethereum’s current volume. Dragonchain has demonstrated that it can handle 250 million transactions a day, and it’s architecture allows for multiple systems to work at that level simultaneously. In our PoC, we demonstrate double the full capacity of Reddit, and every transaction was proven all the way to Bitcoin and Ethereum.
Reddit Scaling on Ethereum
Solutions should not depend on any single third-party provider. We prefer solutions that do not depend on specific entities such as Reddit or another provider, and solutions with no single point of control or failure in off-chain components but recognize there are numerous trade-offs to considerDragonchain’s architecture calls for a hybrid approach. Private business nodes hold the sensitive data while the validation and verification of transactions for the business are decentralized within seconds and secured to public blockchains within 10 minutes to 2 hours. Nodes could potentially be controlled by owners of individual subreddits for more organic decentralization.
Usability Scaling solutions should have a simple end user experience.
Users shouldn't have to maintain any extra state/proofs, regularly monitor activity, keep track of extra keys, or sign anything other than their normal transactionsDragonchain and its customers have demonstrated extraordinary usability as a feature in many applications, where users do not need to know that the system is backed by a live blockchain. Lyceum is one of these examples, where the progress of academy courses is being tracked, and successful completion of courses is rewarded with certificates on chain. Our @Save_The_Tweet bot is popular on Twitter. When used with one of the following hashtags - #please, #blockchain, #ThankYou, or #eternalize the tweet is saved through Eternal to multiple blockchains. A proof report is available for future reference. Other examples in use are DEN, our decentralized social media platform, and our console, where users can track their node rewards, view their TIME, and operate a business node.
Transactions complete in a reasonable amount of time (seconds or minutes, not hours or days)All transactions are immediately usable on chain by the system. A transaction begins the path to decentralization at the conclusion of a 5-second block when it gets distributed across 5 separate community run nodes. Full decentralization occurs within 10 minutes to 2 hours depending on which interchain (Bitcoin, Ethereum, or Ethereum Classic) the transaction hits first. Within approximately 2 hours, the combined hash power of all interchained blockchains secures the transaction.
Free to use for end users (no gas fees, or fixed/minimal fees that Reddit can pay on their behalf)With transaction pricing as low as $0.0000025 per transaction, it may be considered reasonable for Reddit to cover transaction fees for users.
All of Reddit's Transactions on Blockchain (month)
Community points can be earned by users and distributed directly to their Reddit account in batch (as per Reddit minting plan), and allow users to withdraw rewards to their Ethereum wallet whenever they wish. Withdrawal fees can be paid by either user or Reddit. This model has been operating inside the Dragonchain system since 2018, and many security and financial compliance features can be optionally added. We feel that this capability greatly enhances user experience because it is seamless to a regular user without cryptocurrency experience, yet flexible to a tech savvy user. With regard to currency or token transactions, these would occur on the Reddit network, verified to BTC and ETH. These transactions would incur the $0.0000025 transaction fee. To estimate this fee we use the monthly active Reddit users statista with a 60% adoption rate and an estimated 10 transactions per month average resulting in an approximate $720 cost across the system. Reddit could feasibly incur all associated internal network charges (mining/minting, transfer, burn) as these are very low and controllable fees.
Reddit Internal Token Transaction Fees
Reddit Ethereum Token Transaction Fees
When we consider further the Ethereum fees that might be incurred, we have a few choices for a solution.
Users should be able to view their balances & transactions via a blockchain explorer-style interfaceFrom interfaces for users who have no knowledge of blockchain technology to users who are well versed in blockchain terms such as those present in a typical block explorer, a system powered by Dragonchain has flexibility on how to provide balances and transaction data to users. Transactions can be made viewable in an Eternal Proof Report, which displays raw data along with TIME staking information and traceability all the way to Bitcoin, Ethereum, and every other Interchained network. The report shows fields such as transaction ID, timestamp, block ID, multiple verifications, and Interchain proof. See example here.
Node payouts within the Dragonchain console are listed in chronological order and can be further seen in either Dragons or USD. See example here.
In our social media platform, Dragon Den, users can see, in real-time, their NRG and MTR balances. See example here.
A new influencer app powered by Dragonchain, Raiinmaker, breaks down data into a user friendly interface that shows coin portfolio, redeemed rewards, and social scores per campaign. See example here.
Exiting is fast & simpleWithdrawing funds on Dragonchain’s console requires three clicks, however, withdrawal scenarios with more enhanced security features per Reddit’s discretion are obtainable.
Interoperability Compatibility with third party apps (wallets/contracts/etc) is necessary.Proven interoperability at scale that surpasses the required specifications. Our entire platform consists of interoperable blockchains connected to each other and traditional systems. APIs are well documented. Third party permissions are possible with a simple smart contract without the end user being aware. No need to learn any specialized proprietary language. Any code base (not subsets) is usable within a Docker container. Interoperable with any blockchain or traditional APIs. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js. Please see our source code and API documentation.
Scaling solutions should be extensible and allow third parties to build on top of it Open source and extensible
Documentation should be clear and completeFor full documentation, explore our docs, SDK’s, Github repo’s, architecture documents, original Disney documentation, and other links or resources provided in this proposal.
Third-party permissionless integrations should be possible & straightforward Smart contracts are Docker based, can be written in any language, use full language (not subsets), and can therefore be integrated with any system including traditional system APIs. Simple is better. Learning an uncommon or proprietary language should not be necessary.Advanced knowledge of mathematics, cryptography, or L2 scaling should not be required. Compatibility with common utilities & toolchains is expected.
Dragonchain business nodes and smart contracts leverage Docker to allow the use of literally any language or executable code. No proprietary language is necessary. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js.
Bonus Points: Show us how it works. Do you have an idea for a cool new use case for Community Points? Build it!
TIMECommunity points could be awarded to Reddit users based upon TIME too, whereas the longer someone is part of a subreddit, the more community points someone naturally gained, even if not actively commenting or sharing new posts. A daily login could be required for these community points to be credited. This grants awards to readers too and incentivizes readers to create an account on Reddit if they browse the website often. This concept could also be leveraged to provide some level of reputation based upon duration and consistency of contribution to a community subreddit.
Dragon DenDragonchain has already built a social media platform that harnesses community involvement. Dragon Den is a decentralized community built on the Dragonchain blockchain platform. Dragon Den is Dragonchain’s answer to fake news, trolling, and censorship. It incentivizes the creation and evaluation of quality content within communities. It could be described as being a shareholder of a subreddit or Reddit in its entirety. The more your subreddit is thriving, the more rewarding it will be. Den is currently in a public beta and in active development, though the real token economy is not live yet. There are different tokens for various purposes. Two tokens are Lair Ownership Rights (LOR) and Lair Ownership Tokens (LOT). LOT is a non-fungible token for ownership of a specific Lair. LOT will only be created and converted from LOR.
Energy (NRG) and Matter (MTR) work jointly. Your MTR determines how much NRG you receive in a 24-hour period. Providing quality content, or evaluating content will earn MTR.
Security. Users have full ownership & control of their points.All community points awarded based upon any type of activity or gift, are secured and provable to all Interchain networks (currently BTC, ETH, ETC). Users are free to spend and withdraw their points as they please, depending on the features Reddit wants to bring into production.
Balances and transactions cannot be forged, manipulated, or blocked by Reddit or anyone elseUsers can withdraw their balance to their ERC20 wallet, directly through Reddit. Reddit can cover the fees on their behalf, or the user covers this with a portion of their balance.
Users should own their points and be able to get on-chain ERC20 tokens without permission from anyone elseThrough our console users can withdraw their ERC20 rewards. This can be achieved on Reddit too. Here is a walkthrough of our console, though this does not show the quick withdrawal functionality, a user can withdraw at any time. https://www.youtube.com/watch?v=aNlTMxnfVHw
Points should be recoverable to on-chain ERC20 tokens even if all third-parties involved go offlineIf necessary, signed transactions from the Reddit system (e.g. Reddit + Subreddit) can be sent to the Ethereum smart contract for minting.
A public, third-party review attesting to the soundness of the design should be availableTo our knowledge, at least two large corporations, including a top 3 accounting firm, have conducted positive reviews. These reviews have never been made public, as Dragonchain did not pay or contract for these studies to be released.
Bonus pointsSee above
Compatibility with HSMs & hardware walletsFor the purpose of this proposal, all tokenization would be on the Ethereum network using standard token contracts and as such, would be able to leverage all hardware wallet and Ethereum ecosystem services.
Minting/distributing tokens is not performed by Reddit directlyThis operation can be automated by smart contract on Ethereum. Subreddits can if desired have a role to play.
One off point burning, as well as recurring, non-interactive point burning (for subreddit memberships) should be possible and scalableThis is possible and scalable with interaction between Dragonchain Reddit system and Ethereum token contract(s).
Fully open-source solutions are strongly preferredDragonchain is fully open source (see section on Disney release after conclusion).
ConclusionWhether it is today, or in the future, we would like to work together to bring secure flexibility to the highest standards. It is our hope to be considered by Ethereum, Reddit, and other integrative solutions so we may further discuss the possibilities of implementation. In our public demonstration, 256 million transactions were handled in our operational network on chain in 24 hours, for the low cost of $25K, which if run today would cost $625. Dragonchain’s interoperable foundation provides the atmosphere necessary to implement a frictionless community points system. Thank you for your consideration of our proposal. We look forward to working with the community to make something great!
Disney Releases Blockchain Platform as Open SourceThe team at Disney created the Disney Private Blockchain Platform. The system was a hybrid interoperable blockchain platform for ledgering and smart contract development geared toward solving problems with blockchain adoption and usability. All objective evaluation would consider the team’s output a success. We released a list of use cases that we explored in some capacity at Disney, and our input on blockchain standardization as part of our participation in the W3C Blockchain Community Group.
Open SourceIn 2016, Roets proposed to release the platform as open source to spread the technology outside of Disney, as others within the W3C group were interested in the solutions that had been created inside of Disney.
Following a long process, step by step, the team met requirements for release. Among the requirements, the team had to:
The Disney Open Source Committee approved the application known as OSSRELEASE-10, and the code was released on October 2, 2016. Disney decided to not issue a press release.
Original OSSRELASE-10 document
Dragonchain FoundationThe Dragonchain Foundation was created on January 17, 2017. https://den.social/l/Dragonchain/24130078352e485d96d2125082151cf0/dragonchain-and-disney/
submitted by sidhujag to ethereum [link] [comments]
We are excited to participate and present Syscoin Platform's ideal characteristics and capabilities towards a well-rounded Reddit Community Points solution!
Our scaling solution for Reddit Community Points involves 2-way peg interoperability with Ethereum. This will provide a scalable token layer built specifically for speed and high volumes of simple value transfers at a very low cost, while providing sovereign ownership and onchain finality.
Token transfers scale by taking advantage of a globally sorting mempool that provides for probabilistically secure assumptions of “as good as settled”. The opportunity here for token receivers is to have an app-layer interactivity on the speed/security tradeoff (99.9999% assurance within 10 seconds). We call this Z-DAG, and it achieves high-throughput across a mesh network topology presently composed of about 2,000 geographically dispersed full-nodes. Similar to Bitcoin, however, these nodes are incentivized to run full-nodes for the benefit of network security, through a bonded validator scheme. These nodes do not participate in the consensus of transactions or block validation any differently than other nodes and therefore do not degrade the security model of Bitcoin’s validate first then trust, across every node. Each token transfer settles on-chain. The protocol follows Bitcoin core policies so it has adequate code coverage and protocol hardening to be qualified as production quality software. It shares a significant portion of Bitcoin’s own hashpower through merged-mining.
This platform as a whole can serve token microtransactions, larger settlements, and store-of-value in an ideal fashion, providing probabilistic scalability whilst remaining decentralized according to Bitcoin design. It is accessible to ERC-20 via a permissionless and trust-minimized bridge that works in both directions. The bridge and token platform are currently available on the Syscoin mainnet. This has been gaining recent attention for use by loyalty point programs and stablecoins such as Binance USD.
SolutionsSyscoin Foundation identified a few paths for Reddit to leverage this infrastructure, each with trade-offs. The first provides the most cost-savings and scaling benefits at some sacrifice of token autonomy. The second offers more preservation of autonomy with a more narrow scope of cost savings than the first option, but savings even so. The third introduces more complexity than the previous two yet provides the most overall benefits. We consider the third as most viable as it enables Reddit to benefit even while retaining existing smart contract functionality. We will focus on the third option, and include the first two for good measure.
Syscoin + Matic IntegrationMatic and Blockchain Foundry Inc, the public company formed by the founders of Syscoin, recently entered a partnership for joint research and business development initiatives. This is ideal for all parties as Matic Network and Syscoin Platform provide complementary utility. Syscoin offers characteristics for sovereign ownership and security based on Bitcoin’s time-tested model, and shares a significant portion of Bitcoin’s own hashpower. Syscoin’s focus is on secure and scalable simple value transfers, trust-minimized interoperability, and opt-in regulatory compliance for tokenized assets rather than scalability for smart contract execution. On the other hand, Matic Network can provide scalable EVM for smart contract execution. Reddit Community Points can benefit from both.
Syscoin + Matic integration is actively being explored by both teams, as it is helpful to Reddit, Ethereum, and the industry as a whole.
Proving Performance & Cost SavingsOur POC focuses on 100,000 on-chain settlements of token transfers on the Syscoin Core blockchain. Transfers and burns perform equally with Syscoin. For POCs related to smart contracts (subscriptions, etc), refer to the Matic Network proposal.
On-chain settlement of 100k transactions was accomplished within roughly twelve minutes, well-exceeding Reddit’s expectation of five days. This was performed using six full-nodes operating on compute-optimized AWS c4.2xlarge instances which were geographically distributed (Virginia, London, Sao Paulo Brazil, Oregon, Singapore, Germany). A higher quantity of settlements could be reached within the same time-frame with more broadcasting nodes involved, or using hosts with more resources for faster execution of the process.
Addresses used: 100,014
The demonstration was executed using this tool. The results can be seen in the following blocks:
It is important to note that this POC is not focused on Z-DAG. The performance of Z-DAG has been benchmarked within realistic network conditions: Whiteblock’s audit is publicly available. Network latency tests showed an average TPS around 15k with burst capacity up to 61k. Zero-latency control group exhibited ~150k TPS. Mainnet testing of the Z-DAG network is achievable and will require further coordination and additional resources.
Even further optimizations are expected in the upcoming Syscoin Core release which will implement a UTXO model for our token layer bringing further efficiency as well as open the door to additional scaling technology currently under research by our team and academic partners. At present our token layer is account-based, similar to Ethereum. Opt-in compliance structures will also be introduced soon which will offer some positive performance characteristics as well. It makes the most sense to implement these optimizations before performing another benchmark for Z-DAG, especially on the mainnet considering the resources required to stress-test this network.
Cost SavingsTotal cost for these 100k transactions: $0.63 USD
See the live fee comparison for savings estimation between transactions on Ethereum and Syscoin. Below is a snapshot at time of writing:
ETH price: $318.55 ETH gas price: 55.00 Gwei ($0.37)
Syscoin price: $0.11
Snapshot of live fee comparison chart
Z-DAG provides a more efficient fee-market. A typical Z-DAG transaction costs 0.0000582 SYS. Tokens can be safely redeemed/re-spent within seconds or allowed to settle on-chain beforehand. The costs should remain about this low for microtransactions.
Syscoin will achieve further reduction of fees and even greater scalability with offchain payment channels for assets, with Z-DAG as a resilience fallback. New payment channel technology is one of the topics under research by the Syscoin development team with our academic partners at TU Delft. In line with the calculation in the Lightning Networks white paper, payment channels using assets with Syscoin Core will bring theoretical capacity for each person on Earth (7.8 billion) to have five on-chain transactions per year, per person, without requiring anyone to enter a fee market (aka “wait for a block”). This exceeds the minimum LN expectation of two transactions per person, per year; one to exist on-chain and one to settle aggregated value.
Tools, Infrastructure & Documentation
Syscoin BridgeMainnet Demonstration of Syscoin Bridge with the Basic Attention Token ERC-20
A two-way blockchain interoperability system that uses Simple Payment Verification to enable:
APITools to simplify using Syscoin Bridge as a service with dapps and wallets will be released some time after implementation of Syscoin Core 4.2. These will be based upon the same processes which are automated in the current live Sysethereum Dapp that is functioning with the Syscoin mainnet.
DocumentationSyscoin Bridge & How it Works (description and process flow)
Superblock Validation Battles
HOWTO: Provision the Bridge for your ERC-20
HOWTO: Setup an Agent
Developer & User Diligence
Trade-offThe Syscoin Ethereum Bridge is secured by Agent nodes participating in a decentralized and incentivized model that involves roles of Superblock challengers and submitters. This model is open to participation. The benefits here are trust-minimization, permissionless-ness, and potentially less legal/regulatory red-tape than interop mechanisms that involve liquidity providers and/or trading mechanisms.
The trade-off is that due to the decentralized nature there are cross-chain settlement times of one hour to cross from Ethereum to Syscoin, and three hours to cross from Syscoin to Ethereum. We are exploring ways to reduce this time while maintaining decentralization via zkp. Even so, an “instant bridge” experience could be provided by means of a third-party liquidity mechanism. That option exists but is not required for bridge functionality today. Typically bridges are used with batch value, not with high frequencies of smaller values, and generally it is advantageous to keep some value on both chains for maximum availability of utility. Even so, the cross-chain settlement time is good to mention here.
CostEthereum -> Syscoin: Matic or Ethereum transaction fee for bridge contract interaction, negligible Syscoin transaction fee for minting tokens
Syscoin -> Ethereum: Negligible Syscoin transaction fee for burning tokens, 0.01% transaction fee paid to Bridge Agent in the form of the ERC-20, Matic or Ethereum transaction fee for contract interaction.
Z-DAGZero-Confirmation Directed Acyclic Graph is an instant settlement protocol that is used as a complementary system to proof-of-work (PoW) in the confirmation of Syscoin service transactions. In essence, a Z-DAG is simply a directed acyclic graph (DAG) where validating nodes verify the sequential ordering of transactions that are received in their memory pools. Z-DAG is used by the validating nodes across the network to ensure that there is absolute consensus on the ordering of transactions and no balances are overflowed (no double-spends).
APISyscoin-js provides tooling for all Syscoin Core RPCs including interactivity with Z-DAG.
DocumentationZ-DAG White Paper
Useful read: An in-depth Z-DAG discussion between Syscoin Core developer Jag Sidhu and Brave Software Research Engineer Gonçalo Pestana
Trade-offZ-DAG enables the ideal speed/security tradeoff to be determined per use-case in the application layer. It minimizes the sacrifice required to accept and redeem fast transfers/payments while providing more-than-ample security for microtransactions. This is supported on the premise that a Reddit user receiving points does need security yet generally doesn’t want nor need to wait for the same level of security as a nation-state settling an international trade debt. In any case, each Z-DAG transaction settles onchain at a block target of 60 seconds.
Syscoin SpecsSyscoin 3.0 White Paper
(4.0 white paper is pending. For improved scalability and less blockchain bloat, some features of v3 no longer exist in current v4: Specifically Marketplace Offers, Aliases, Escrow, Certificates, Pruning, Encrypted Messaging)
WalletsWeb3 and mobile wallets are under active development by Blockchain Foundry Inc as WebAssembly applications and expected for release not long after mainnet deployment of Syscoin Core 4.2. Both of these will be multi-coin wallets that support Syscoin, SPTs, Ethereum, and ERC-20 tokens. The Web3 wallet will provide functionality similar to Metamask.
Syscoin Platform and tokens are already integrated with Blockbook. Custom hardware wallet support currently exists via ElectrumSys. First-class HW wallet integration through apps such as Ledger Live will exist after 4.2.
Current supported wallets
Syscoin Spark Desktop
ExplorersMainnet: https://sys1.bcfn.ca (Blockbook)
Thank you for close consideration of our proposal. We look forward to feedback, and to working with the Reddit community to implement an ideal solution using Syscoin Platform!
https://preview.redd.it/hml53mmh5er41.png?width=568&format=png&auto=webp&s=3f0cd662e1836bcb2ea37793cbbbfd6f8a5e9723submitted by Floris-Jan to aelfofficial [link] [comments]
It’s always great to hang out in this group. This group means a lot to the Aelf community. It is the first Aelf community and has been there through all the ups and downs in the world. I would like to start with wishing everyone is staying safe at home during the virus outbreak. It definitely has been a difficult time for all of us, but together we can pull through it.
We understand that the situation is quite striking to all of us. But I really believe that the solution to the virus outbreak is about more global coordination and collaboration.
All of you to be assured, our team in different places are all safe and working from home as normal.
The Aelf team in Beijing were among the early ones experiencing the virus outbreak. As everyone was on the way home for Lunar New Year holiday and then experienced a total city lock-down followed by a 40 days’ work from home policy. It was definitely not easy for them, but our team stayed strong, took necessary precautions and focused on work with the right morale. Mappo has recently published some tips on how to work from home effectively based on our experience. Do check it out. Despite not working in the office since February, we have achieved great progress, including launching Aelf 1.0 preview, which is an important milestone in technical delivery and also the roadmap to mainnet launch (which listed out the essential steps for the community to work together to launch a successful public network)
Let's first talk about Aelf v1.0 preview. It is the cornerstone of the mainnet launch. The product itself has all the features that the public network is needed. The codebase has been reviewed and tested rigorously by the team. And a few highlights of how the network would look like:
So how are we going to help the community launch the network:
First of all, we have launched the codes, documents about the economic system and governance model and technical features. With all the things available, you are able to understand what the system is about, as a token holder what's your benefit in the system, and being a node in the system plays a big role in the governance
Next, without yet electing the nodes, we will get all token holders to join the current Aelf network through a mapping event. That means as long as you have Aelf tokens, you will be able to get 1:1 test tokens on the public testnet. that gives you full access to all the features, and you will feel like you are already using the mainnet. You will get rewarded in making transactions, voting, etc.
Do try out the Aelf wallet and voting features, you will see how easy to transfer tokens cross-chain. and also how flexible the system allows people to make changes. For example, the community may want to adjust the block rewarding parameters or fees to use certain services on mainnet, they can initiate a discussion and then vote in the system and once voted through, it will be reflected on mainnet.
For people or organizations that want to play a bigger role in the system, we will do a dry run of node election. Take it as the real node election before mainnet launch. We will see who the active members of the community are and being trusted by the community. Among the nodes, we will form a network launch committee. The committee will be the crucial party to oversees and ensures the smooth launch of Aelf mainnet, instead of just relying on the Aelf team. This is our step towards decentralization.
The committee will agree on the actual launch process, final checking all the parameters in the system to be ready for launch and then decide when the criteria are met to launch the network. Once all that is decided. We will invite all interested nodes to apply for the election and let the community know what's their plan to grow the Aelf network. the network will initially be launched with a few nodes from the committee and gradually be replaced by the selected nodes (a bootstrap phase). Along the way, we will work with exchanges to conduct token swap (which we are also designing an innovative system to further enhance security and usability of Aelf tokens in exchanges)
Among this isolated and worrisome time, at least we all have something to look forward to: a successful launch of Aelf network! Once it is launched, we are excited to see a vibrant and technically superior network that is good for Dapps to run on top of it.
Doris Guo Q1: As a Blockchain start-up, what difficulties have you overcome when starting Aelf project? What motivates you to solve difficulties and achieve success today?
Zhuling Chen First, just like launching any start-up, its community and investors are usually regional. There is always some bias on if Asian projects are solid. It is really rare to have an Asian project to be supported by western funds and community from day 1. We were lucky to have overcome that obstacle. Having a global investor line-up from day 1. Having a global team from day 1 and also working with a global community from day 1. This benefited us to have an international perspective which is crucial in the blockchain industry.
Secondly, as a hardcore technology company, it is really hard to put in plain words what is our ambition. Our ambition is huge, achieving key innovations in multiple fronts of blockchain technology and organically combined them to serve real users for the future. Our marketing team has been working really hard to elaborate on what Aelf is. Now we have come to a point that the product is ready. Therefore, it is much easier for all of us to understand how solid Aelf is by trying out the network ourselves! That's exactly what the following events will be about - Try out all the exciting features of Aelf network before mainnet launch.
Doris Guo Q2: What critical problems do you see occurring in the blockchain industry nowadays? How does Aelf solve these problems?
Haobo Ma First, we need to distinguish the difference between BTC and ETH. One is Digital Cash and the other is the Smart Contract Platform. Aelf addresses most of the latter's problems. In short, it can be summarized as performance, end-user friendly, developer-friendly, network economy, and self-governance and upgrading. Each of these areas will probably take up a lot of space, and as a whole are the issues described in our two white papers. In short, Aelf is faster, end-users do not need to know the rules of the blockchain, developers can set up the development environment in 10 minutes, have a good economic model and can carry out proposal governance on the chain.
Doris Guo Q3: What is your long-term vision about the industry which Aelf is working at? Are you afraid someday there will be another project with more innovative technology can replace Aelf?
Haobo Ma Let's talk about where Aelf stands in the traditional Internet. It is essentially a cloud service provider, Aelf provides resources and infrastructure for developers to deploy their services, known as smart contracts. We eventually want Aelf to grow like AAA (Amazon, Azure, AliCloud). Because Aelf is a network that can be dynamically scaled, we can accept any new technology, some of the more advanced technologies we can put on a side chain.
Doris Guo Q4: Why did Aelf choose for cross-chain interaction?
Haobo Ma As I mentioned earlier, Aelf solves the Smart Contract Platform problem. However, there are other digital cash problems as well which we would need to use existing infrastructure such as Bitcoin's chain in order to interact with Bitcoin. There are a lot of infrastructures on Ethereum that we want to interact with. Multi-chain on Aelf network mainly is to isolate resources to improve network performance and network stability.
Doris Guo Q5: What difficulties do the Aelf team have now (I talk about COVID-19)? How does the Aelf team solve it? Have you changed the roadmap?
Haobo Ma There is no great impact. The teams in Singapore and Beijing are communicating with each other remotely on a regular basis. The only change is that most of us are now working from home which has no impact and in fact, it seems conducive to the acceptance of more community developers in the future to come. From the internal working schedule and development timeline, there is no great impact. We do not publish specific timeline as we do not want short term holders (traders) to create too much negative pressure on product development.
Doris Guo Q6: Aelf is an open-source blockchain, and there's the common problem of taking a substantial amount of time for the different participants to agree on strategic decisions. What types of governance models do you use in Aelf to address this issue???
Haobo Ma The issue is about public blockchain network, and who can decide the direction of the network. Our answer is long-term holders. For the short-term holders (traders), we refuse to allow them to participate in any discussion of the direction of Aelf because the short-term holders are likely to make a profit and sell quickly, which is essentially the same example of a person who cheats the President and then runs away for his personal gain. We defined a number of proposal processes, including the logic of the two-party system in the United States, and the participation in the referendum to ensure that the final proposal represents the majority. At the same time, we are looking for some legal solutions to avoid bifurcation, such as prohibiting exchanges from intervening in bifurcated new tokens. While we cannot limit a community, we should be able to find ways to limit a centralized organization. This restriction is akin to a ban on national secession.
Doris Guo Q7: How will Aelf empower Investors, Companies, Developers, Platform Users to deliver impactful solutions and bring value to people all over the world?
Haobo Ma We will learn from the operational experience of successful foundations such as the LINUX foundation and license some commercial companies to use Aelf solutions to solve business problems. At the same time, Aelf is an open-source product under the MIT License, and we accept any use that does not violate this open-source principle.
Zhuling Chen Let me add on to Haobo’s statement: to incentivize and empower the community, we are also exploring ways to let the community decide how to use the funds for Aelf (allocate to where it matters to our community) once mainnet is launched. This means you guys can decide what are the projects to be funded on Aelf, etc
Doris Guo Q8：When will the node campaign start? How will Aelf attract users to participate in nodes election?
Haobo Ma According to our published roadmap, the timeline can be dynamic, but I don't think it will be too long. The main idea is to let everyone understand what we envision Aelf to be like, and what are the rights and benefits of being a node in the future. We hope to find nodes that fully recognize the efforts of Aelf at the present stage and are willing to participate in the future development of Aelf. We will run a simulation of the node campaign on the testnet and set up a temporary mainnet launch committee. Please follow our official Twitter for more upcoming details!
Doris Guo Q9: Token swap form 2 is some kind of cross-chain transfer? It will be handled by a smart contract?
Haobo Ma It is handled by the smart contract, we define an asset cross-chain transfer protocol, but it may be opened after a snapshot.
Doris Guo Q10: Which Exchanges will support token swap? Do you have any plan to list Aelf in some big exchange like Binance, Houbi, Kucoin, .......?
Haobo Ma We are already in talks with some exchanges, there is still competition between exchanges, and many are still hoping to attract more users by getting access to mainnet token swap early.
Doris Guo Q11: Aside conversion of the current tokens to mainnet tokens, what other main features will be accomplished with the mainnet launch?
Haobo Ma We have a documentation file that has been published, which has listed some features: https://Aelf.io/gridcn/Aelf_public_testnet_and_supporting_features_introduction_en_v1.0.pdf
Doris Guo Q12: Do you have any plan to burn or buyback your coin?
Haobo Ma We have plans for the community to govern through DAO, we have no interest in short-term price incentive adjustment as we would prefer to drive the project to higher adoption. After mainnet starts operation, there will be a part of network revenue get destroyed automatically.
Doris Guo Q13: Often, as a newbie developer, I face difficulties on most blockchains. How easy and convenient is it for me on Aelf, and what programming language and tools are needed??
Haobo Ma We set up staging for DAPP developers on GitHub and configured CI. Develop a smart contract using C# with React Native on the front end. So, in fact, developers can fork the source code without setting up the environment locally, and you can conduct unit testing with the help of CI. You can also release the smart contract and generate the installation package of iOS and android online. https://github.com/AElfProject/Aelf-boilerplate
Doris Guo Q14: What is the progress of business development and what are some of your commercial partnerships? How will Aelf rapidly develop the number & performance of DAPP?
Haobo Ma First of all, the blockchain industry is still fairly small and users with ETH and EOS wallets are considered a very small group and its not effective to even promote within these groups. What we need to consider is how to enable users who have never been exposed to blockchain to use DAPP. The competitiveness of Aelf is to make it easier for Aelf developers to promote their DAPP to ordinary users, rather than to teach ordinary users a lot on blockchain knowledge. The average user doesn't like to hear about private keys, mnemonic, Gas Price, RAM, CPU, etc. Only until we solve such problems, companies that need to solve problems through blockchain will be more inclined to use Aelf in technology selection. Therefore, our main work is to explain the competitive advantages of Aelf, ETH and EOS to everyone. We have some business cooperation’s, but we also believe that simply through case-by-case business cooperation will not be able to gain adoption so quickly, therefore we still need to put our products to stay ahead of the next generation.
Doris Guo Q15: What other activities can encourage more people to be confident about Aelf?
Haobo Ma We are only going to state the truth by having those that have faith in us to stay and those that don't to leave. The development of Aelf is not driven by a single foundation, but by a steady stream of contributions from the community. In the future, we will also place the activities in the DAO for on-chain governance, and let the community make decisions by itself.
Kun Aguero As you know that in the present market situation many new coins or either dying or thriving for liquidity? How will you manage this liquidity problem?
Zhuling Chen Aelf started in 2017. we have gone through a few cycles in the market, still, remember the big down period in 2018-2019. Aelf is financially solid and the team has always been working hard. if you are referring to liquidity in exchanges, we are among the lucky ones that are listed in all major exchanges
Xinshu Dong Hello, great discussions! I would like to ask what are the criteria to join the committee for launching the mainnet? Would love to participate
Zhuling Chen Hi xinshu, great to see you here. The committee will be chosen among the nodes elected during the testnet dry run. Which means, it is really important to participate in the testnet dry run and also start to establish your reputation in the community so that people will elect you as a node. The detailed criteria will include what is your plan to help Aelf to grow, tech competency and reputation.
An Da What are Aelf’s achievements in 2019? Who had supported you to get those things?
Zhuling Chen To name a few, in 2019, Aelf is one of the most active projects on GitHub. This means Aelf is evolving and improving fast in this space and our team has the tech strength. In addition, we have also successfully listed on all major cloud service providers, such as AWS, Azure, Google. So large companies can easily launch Aelf side chains in their organization with minimum hassle.
John How does the voting for master nodes candidates occur? And why is the development of this system important for your project?
Zhuling Chen Voting is going to be pretty simple. All token holders can vote for the nodes they support on our block explorer.
Miha After mainnet lunch, how will you assure that transactional fees will stay low? We know what sometimes happens to fees on ETH blockchain.
Zhuling Chen First of all, due to the fact that is Aelf is scalability, this will reduce transaction fee. Secondly, all transaction fees will be voted by the nodes (which will be elected by you). So they will represent your interest
Bobbyfernandito Currently, as we see All projects are concerned with the speed and security. So, tell us here - what are the facilities Aelf provide to their user and investors?
Haobo Ma Security: we have an automated smart contract code audit. During contract deployment, production nodes and the community audit participation are required. On the other hand, we are also planning to provide a standardized model of centralized exchange access for 100% asset certification and emergency measures to deal with exchange attacks, which we will be released later. Speed: Aelf has been working on improving performance, which is transparent to users which they can also experience by themselves.
An Da What effect does Aelf token have on the Aelf ecosystem? Holding Aelf, what benefits will users receive?
Zhuling Chen Holding ELF enables you to use all the services on the Aelf network. ELF has a deflating system where the total amount will reduce as the network grows. token holders can also vote for the nodes to run the network and also vote for big decisions in the network. part of the fees in the system will also be distributed to token holders via a smart contract
ahihi132 Which companies do you view them as potential partners and that they are somewhat also beneficial for both the user base and Aelf itself?
Zhuling Chen Great question, if I could write a wish list, that will be: let medium-sized financial institutions to use Aelf to challenge the big boys. Let telecommunication companies use Aelf for micro-payment and other innovative business models. We also would like to try out a few public sector projects, which blockchain will is still more transparency and trust
Misun Q1: Which programming languages are you using in your project? And why? Q2-What are another big MILESTONES you have planned for 2020 roadmap and how are they supposed to benefit your costumers? Will it be an exciting year?
Haobo Ma For Q1: We mainly use C# for development, I personally like it. Performance is good, development environment IDEs are strong, and C# creators are influential in the industry. We believe in the right thing, though it may take a while to develop. The smart contract will then add support for multiple languages, such as WebAssembly, depending on the needs of the community. Now it seems that C# is enough.
Hambi crypto Which platforms are your competitors? How will you soar above them, and what better things do you offer than them? So, What’s your outlook on the future of cryptocurrencies in this year and next few years?
Haobo Ma As I have already mentioned this before, Eth and Eos. We provide better performance, cross-chain support (already implemented), end-users do not need to know the details of the blockchain, developer’s payment models and so on.
Floris-Jan What plans is Aelf making to prevent centralized exchange to take over the DPoS algorithm like what happened to Steem? Are we talking about blacklisting exchange wallets, or having the foundation say "No", or putting all trust in the community?
Zhuling Chen Great question, Floris. I’m not going to give away all the details of what Haobo has proposed to work on this, but in a nutshell, in Aelf system, exchange wallets will not be allowed to vote, but only the sub-wallets for each individual can vote. This will also help exchanges to prevent hacking and theft in the future
Alex What your plans in place for global expansion, are Aelf wallet focusing on the only market at this time? Or focus on building and developing or getting customers and users, or partnerships? Can you explain this?
Haobo Ma Our core focus will be through the developers to promote, developers will help Aelf to attract more users. So our product has to be attractive to developers. Just like AWS, they only focus on getting their service right, their developers will think about how to promote it. We don't want to burden them in their promotion process.
Ellkay What do you think are the major threats and barriers that could face the development and adoption of Aelf?
Haobo Ma If I'm a DAPP developer and I need to promote my APP to people who don't recognize blockchain, then I'd like to choose a platform that doesn't have to explain a lot of blockchain details to the end-user, so they can use it easily. We've provided some options in the Boilerplate that allow you to log-in simply via QR code + Password, and our recommended Dapp is an independent wallet and a separate iOS/Android application.
ahihi132 Give me some important reasons why we need to hold Aelf token where in fact hundreds of projects failed and it went to bankruptcy or even developers run when they collect millions/billions of funds?
Haobo Ma First of all, we will not give any suggestions as we only describe the fact that the long-term token holder will be able to govern the Aelf network, get Aelf mining reward and Aelf network profit. At the same time, Aelf network is a deflation model, Aelf network received transaction fees, profit dividends will immediately destroy 10% etc. All investments are risky, and we don't judge the behaviour of other developers. There are so many things in this world that cannot be understood and unfair. It is important to do our job well. I cannot explain these things.
胖 见愁 I remember that boss Ma mentioned to only find those truly innovative applications and enterprises with blockchain, how to find and win partners in these aspects?
Haobo Ma When Linus was developing Linux, I did not think he would find a lot of collaboration when the code was not good. The response we can give is that we already have a lot of interest in cooperation, including what we have announced, what we have not announced, etc.
胖 见愁 How interested are cloud computing providers in participating nodes?
Haobo Ma The vast majority of our nodes should be using cloud services, and as long as a large number of our 17 nodes and other candidate nodes are based on cloud services, our network robustness is determined by these cloud computing providers. Of course, in the expansion, we can also use cloud computing services.
[index]          
Hello and welcome to the '24 Hours of Bitcoin', presented by Introtocryptos.ca, this bitcoin trading live stream is like a long, slow bitcoin trading lesson dripped out over time! my name is Doug ... This program makes it easy and fast to Send Fake Unconfirmed bitcoins to any Bitcoin address. For tool contact at:: [email protected] The Bitcoin Fake Transaction by RBF method is a ... ** Edureka AWS Certification ... This Edureka video on "AWS Full Course" is a complete AWS Tutorial for beginners w... CC; 11:56:22. Python Full Course - Learn Python in 12 Hours Python Tutorial ... We are not certified financial planners/advisors nor certified financial analysts. The contents on this video and our sites are for informational and entertainment purposes only and do not ... Udemy Free Certification Course for Limited time Chandan Patel Telegram https://t.me/chandanpatel19 Courses Link ----- Python for beginn... Welcome to Crypto Download, a weekly show featuring cryptocurrency news and commentary. In today’s video, we’re going to cover and share our thoughts on: 0:45 France says no to crypto-to ... 🛑 VECHAIN SPOTLIGHTS SINGAPORE FOR A BUSY NOVEMBER. Subscribe: Subscribe & 🔔 to Fool with Money for more cryptocurrency News & Insights: https://www.youtub... Will Bitcoin Crash? We are not sure if Bitcoin will crash, in this video we are sharing the potential reasons, why Bitcoin can crash? 1-Finacial reasons 2-Technical reasons 3- Regulatory reasons ... Cloud Certification Training 59,387 views. 14:28. How to create your own parity node on AWS in 5 minutes - Duration: 5:51. etherisc 2,336 views. 5:51. Deploying Hyperledger Fabric Blockchain ... A sample AWS Certified Solutions Architect video from the BackSpace Academy AWS Certified Solutions Architect course. More at backspace.academy