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Ethereum Wire Protocol

A Beginners Guide To0x

A Beginners Guide To0x

As an advisor to the Ethereum project 0x (zero-ex), Ive spent a lot of time thinking about and answering questions about how the technology works and its potential impact. Hopefully, this beginners guide will provide a clear introduction to the project and how it will allow anyone in the world to operate an exchange for Ethereum tokens. Before learning about 0x, it is important to first understand the basics of Ethereum tokens. Please see my beginners guide for those new to this concept entirely. According to the 0x whitepaper , 0x is an open protocol for decentralized exchange on the Ethereum blockchain. 0x is creating a protocol using Ethereum smart contracts for anyone in the world to operate a decentralized exchange. The team believes that there will be thousands of Ethereum tokens in the future and there will be a need to trustlessly and efficiently exchange them. This post should help those who are new to 0x to understand how it is different than a centralized or decentralized exchange. If you have ever purchased digital currencies with traditional payment methods like a bank account or wire, then you used a centralized exchange. Centralized exchanges are necessary for providing a fiat on-ramp to the cryptocurrency markets. They typically are easy to use, offer high performance trading, and advanced tools. However, the downsides to centralized exchanges include the downsides to any centralized service that requires trust: the central party could get shut down, hacked, or run away with customer funds. These risks led to the development of decentralized exchanges like EtherDelta and OasisDEX which allow people to trustlessly exchange through the Ethereum blockchain without needing to deposit their funds into the custody of a central party. Another key difference be Continue reading >>

Ethereum On A Iphone Decentralize Today

Ethereum On A Iphone Decentralize Today

Getting started with Ethereum apps on iOS There is no installation package, build by the Ethereum community, ready for the iOS. But in a way it is possible to build something. Let us start with the Ethereum client architecture to see what we have. Ethereum is an example of a very fast growing blockchain implementation. Actually, Ethereum has surpassed Bitcoin in amount of nodes in the public network, at this writing moment, see the current number of nodes . Ethereum is a cryptocurrency. Ether is the currency. Ethereum was created as a clone of the Bitcoin core, having its own blockchain network - a public, distributed ledger. The Ethereum network is called P2P Wire Protocol Network. The most exceptional: Ethereum has a whole programing platform on top of its cryptocurrency, implemented in every client. The programs are called DApps, Decentralized Applications. People are doing things in Ethereum that are not possible right now in Bitcoin. It has created a new generation of developers which never worked with Bitcoin but are interested in Ethereum. See story from Coinbase . What is very real, though, is the possibility that Ethereum blows past Bitcoin entirely. See r3cev.com/blog/2016/5/29 Every node in the network is called a Ethereum Client and it has nothing to do with a client-server architecture. There are only clients nodes in the Ethereum network. Where the Bitcoin blockchain distinguish between a full-node, having a full copy of all transactions, and a lightweight node, having only what is needed for a wallet, the Ethereum has only full-nodes. But there is being working on a lightweight node, see what-should-i-install-on-a-mobile-tablet . Meaning, we must wait on the official Light Client for the mobile devices. While we are waiting on a lightweight solution for Continue reading >>

Signal Protocol - Wikipedia

Signal Protocol - Wikipedia

This article is incomplete. This is because the article is currently missing information about how the Signal Protocol functions. A detailed description can be found in Cohn-Gordon et al. 2016 . Please help to improve it, or discuss the issue on the talk page . The Signal Protocol (formerly known as the TextSecure Protocol) is a non- federated cryptographic protocol that can be used to provide end-to-end encryption for voice calls, video calls, [3] and instant messaging conversations. [2] The protocol was developed by Open Whisper Systems in 2013 [2] and was first introduced in the open source TextSecure app, which later became Signal . It has since been implemented into closed source applications, such as WhatsApp , which is said to encrypt the conversations of "more than a billion people worldwide". [4] Facebook Messenger also say they offer the protocol for optional "secret conversations", as does Google Allo for its "incognito mode". The protocol combines the Double Ratchet Algorithm , prekeys, and a triple DiffieHellman (3-DH) handshake, [5] and uses Curve25519 , AES-256 and HMAC-SHA256 as primitives . [6] The Signal Protocol's development was started by Trevor Perrin and Moxie Marlinspike (Open Whisper Systems) in 2013. The first version of the protocol, TextSecure v1, was based on Off-the-Record Messaging (OTR). [7] [8] On 24 February 2014, Open Whisper Systems introduced TextSecure v2, [9] which migrated to the Axolotl Ratchet. [7] [10] The design of the Axolotl Ratchet is based on the ephemeral key exchange that was introduced by OTR and combines it with a symmetric-key ratchet modeled after the Silent Circle Instant Messaging Protocol (SCIMP). [1] It brought about support for asynchronous communication ("offline messages") as its major new feature, as well as Continue reading >>

Ethereum/devp2p

Ethereum/devp2p

i heard rumour at Devcon3 that libp2p might be used in major eth implementations but haven't got confirmation on that, is it true and if so what's the implications for devp2p @jarradh Have you seen the blog article from Felix on this: ? Also this from Felix Lange. It's clear from that discovery v5 is the priority, and he mentions being able to delete RLPx maybe 2020. So...udp.go line 588 What we have here is that a FindNode to a bootnode with your own id as the parameter will not work What do I need to do to get my own id into the list of known ids? Some kind of ping/pong handshake? Can @fjl update the wiki or something at least? Or point me to where this protocol is documented? How are things coordinated at this level between geth/parity/etc? It seems there are pretty fundamental things just going undocumented. Can you please help me join the dots across the p2p technologies? Where/how is the Ethereum sub-protocol plugged in Vp2p protocol? Do APIs of an SDK (say, Javascript) map to Ethereum sub-protocol message IDs? Or, only geth maps to message IDs? I asked here - but, didn't receive response. What do you mean with 'plugged in'? The devp2p protocol is to establish a handshake with a peer and after that you can communicate in any of the advertised capabilities with your peer. @nicksavers Well, the document seems to give an impression that, Vp2p supports a number of sub-protocols e.g. Ethereum Wire Protocol. Suppose, I want to introduce a new sub-protocol. How do I use Vp2p? @chainhead I can see where you are coming from. The documentation is unclear at best, and unfortunately, not maintained. However: A key paragraph is this "Message IDs are assumed to be compact from ID 0x10 onwards (0x00-0x10 is reserved for Vp2p messages) and given to each shared (equal-version, eq Continue reading >>

Ethereumjs-devp2p - Npm

Ethereumjs-devp2p - Npm

Distributed Peer Table (DPT) / Node Discovery Maintain/manage a list of peers, see ./src/dpt/ , alsoincludes node discovery ( ./src/dpt/server.js ) const dpt = new DPT(Buffer.from(PRIVATE_KEY, 'hex'), { endpoint: { address: '0.0.0.0', udpPort: null, tcpPort: null }}) Add some bootstrap nodes (or some custom nodes with dpt.addPeer()): dpt.bootstrap(bootnode).catch((err) => console.error('Something went wrong!')) Distributed Peer Table. Manages a Kademlia DHT K-bucket (Kbucket) for storing peer informationand a BanList for keeping a list of bad peers. Server implements the node discovery (ping,pong, findNeighbours). privateKey - Key for message encoding/signing. options.refreshInterval - Interval in ms for refreshing (calling findNeighbours) the peer list (default: 60s). options.createSocket - A datagram (dgram) createSocket function, passed to Server (default: dgram.createSocket.bind(null, 'udp4')). options.timeout - Timeout in ms for server ping, passed to Server (default: 10s). options.endpoint - Endpoint information to send with the server ping, passed to Server (default: { address: '0.0.0.0', udpPort: null, tcpPort: null }). Uses a peer as new bootstrap peer and calls findNeighbouts. peer - Peer to be added, format { address: [ADDRESS], udpPort: [UDPPORT], tcpPort: [TCPPORT] }. object - Peer to be added, format { address: [ADDRESS], udpPort: [UDPPORT], tcpPort: [TCPPORT] }. For other utility functions like getPeer, getPeers see ./src/dpt/index.js . Connect to a peer, organize the communication, see ./src/rlpx/ const rlpx = new devp2p.RLPx(PRIVATE_KEY, { dpt: dpt, maxPeers: 25, capabilities: [ devp2p.ETH.eth63, devp2p.ETH.eth62 ], listenPort: null}) Manages the handshake (ECIES) and the handling of the peer communication (Peer). privateKey - Key for message encoding/ Continue reading >>

Ethereum Gossip Protocol

Ethereum Gossip Protocol

It is a communication protocol. Sawtooth currently relies on a gossip protocol to ensure that all messages about transactions and blocks are delivered to all nodes on the network. Why are they creating Ethereum Classic, which can be called the most popular variation of Ethereum, has had an update with the ECIP 1017 solution. 10. 2. Here comes the first Frontier patch, and this is a big one! Pryze, the automated sweepstakes protocol built on the Ethereum blockchain, plans to unveil its highly anticipated platform for companies to hold faster, cheaper, and At a fundamental level 0x is an open protocol for decentralized exchange on the Ethereum Blockchain and is intended to act as a basic building block that may be The Melon protocol is a blockchain protocol for digital asset management on the Ethereum platform. This is a theoretical question about how gossip protocols work; I am not asking about any specific implementation or piece of software. This quickstart guide will help you get started implementing an Ethereum blockchain network on Azure. Jeff Desjardins. While Bitcoin nodes make only eight outgoing TCP connections to form the gossip network that network based on a protocol called Ethereum versions (prior to In a new research paper titled Low-Resource Eclipse Attacks on Ethereums Peer-to-Peer the protocol based on the to form the gossip network that I'm reading about Casper protocol and the hybrid solution that Ethereum is going to adopt in the first place. You can read the following links to get a deeper view: 3. Anything to do with development on the Ethereum blockchain protocol and the Ethereum clients Read our complete Beginner's Guide to Ethereum Casper Hardfork: What You Need to Know about the move to Proof of Stake and How you Can Benefit The non-profit dedi Continue reading >>

Ocalog: The Original Content Catalog

Ocalog: The Original Content Catalog

Ethereum is a cryptocurrency where code can be executed on theblockchain. This capability allows "smart contracts" to be writtenwhich execute themselves automatically. About a year ago, a smartcontract called the DAO blew up spectacularly when someone figured outhow to manipulate it into giving them what was then $41 million worthof Eth. This caused a fracturing of the network when people decided to"fork" the blockchain to one where the DAO attack never happened.When I first heard about this, I thought "that sounds like so muchfun" but I haven't had time to gain a deep understanding of how itworks, until now. This is the first post in a series on the fullimplementation of the Ethereum protocol from a beginner's perspective.After this first post, I plan to write these posts in digestiblechunks so that you don't have to spend too much time reading themevery day, but over time you will gain a deeper understanding ofEthereum.I'm going to assume the reader has a basic understanding of Python,git, knowledge (not expertise) of network concepts like TCP and UDP,and no fear of working with raw bytes. Other than that I will try toassume nothing. Today I will start with a conceptual introduction tocryptocurrency, then set up a Python development environment, andfinally implement `ping` on the Ethereum network. Let's get started.### The concept of cryptocurrencyA cryptocurrency is a means of storing and transferring valueelectronically without a central settlement mechanism. A centralsettlement mechanism keeps track of all accounts, updates them foreach transaction, and acts as a trusted third party for alltransactions. In the United States, the Federal Reserve System is thecentral settlement mechanism. All banks have accounts at the Fed anduse its authority to settle transactions Continue reading >>

Where Can I Find Details On Ethereum Network Protocols, Block Formats And So On? : Ethereum

Where Can I Find Details On Ethereum Network Protocols, Block Formats And So On? : Ethereum

Where can i find details on Ethereum network protocols, block formats and so on? I want to understand how Ethereum works, and for me to understand equals to implement. So, i want to write a rudimentary Ethereum node, capable of connecting directly to the live testnet, interacting with it, parsing the data structures and so on. In case of Bitcoin-class coins, there are resources like which describe between-nodes protocol, and many block explorers have a raw hex output modes for everything. In Ethereum, however, i can't find anything more than the list of bootnodes in the code. I'm yet to see a raw hex version of a single block, and the way nodes communicate is not even referenced or mentioned anywhere - only APIs for various web sites are discussed. I'm trying to find something to hook onto and start building from, but find myself just sliding along the skin of this slippery cthulhu without a single orifice in sight. TL;DR: Where can i find details on low-level ethereum stuff, or at least where in the code (preferably cpp-ethereum one) can i find the network stuff and block structure? Continue reading >>

State Tree Pruning - Ethereum Blog

State Tree Pruning - Ethereum Blog

One of the important issues that has been brought up over the course of the Olympic stress-net release is the large amount of data that clients are required to store; over little more than three months of operation, and particularly during the last month, the amount of data in each Ethereum clients blockchain folder has ballooned to an impressive 10-40 gigabytes, depending on which client you are using and whether or not compression is enabled. Although it is important to note that this is indeed a stress test scenario where users are incentivized to dump transactions on the blockchain paying only the free test-ether as a transaction fee, and transaction throughput levels are thus several times higher than Bitcoin, it is nevertheless a legitimate concern for users, who in many cases do not have hundreds of gigabytes to spare on storing other peoples transaction histories. First of all, let us begin by exploring why the current Ethereum client database is so large. Ethereum, unlike Bitcoin, has the property that every block contains something called the state root: the root hash of a specialized kind of Merkle tree which stores the entire state of the system: all account balances, contract storage, contract code and account nonces are inside. The purpose of this is simple: it allows a node given only the last block, together with some assurance that the last block actually is the most recent block, to synchronize with the blockchain extremely quickly without processing any historical transactions, by simply downloading the rest of the tree from nodes in the network (the proposed HashLookup wire protocol message will faciliate this), verifying that the tree is correct by checking that all of the hashes match up, and then proceeding from there. In a fully decentralized co Continue reading >>

Light Ethereum Subprotocol - Wiki Parity Tech Documentation

Light Ethereum Subprotocol - Wiki Parity Tech Documentation

The Light Ethereum Subprotocol (LES) is the protocol used by light clients, which only download block headers as they appear and fetch other parts of the blockchain on-demand. They provide full functionality in terms of safely accessing the blockchain, but do not mine and therefore do not take part in the consensus process. Full and archive nodes can also support the LES protocol besides ETH in order to be able to serve light nodes.It has been decided to create a separate sub-protocol in order to avoid interference with the consensus-critical ETH network and make it easier to update during the development phase. Some of the LES protocol messages are similar to the new sync model (ETH62/63) of the Ethereum Wire Protocol , with the addition of a few new fields (see below). This version of the spec may differ from the one at Zsolt Felfldis fork of geth , which is the original source of this page. This version will house useful adjustments to the protocol which are eventually intended to be merged upstream so there arent competing versions of the protocol. Every on-demand request message contains a reqID field, which is simply returned by the server in the corresponding reply message. This helps matching replies for requests on the client side so that each reply doesnt need to be matched against each pending request. Every reply message contains a BV (Buffer Value) flow control feedback field, see Client Side Flow Control Messages of the LES/1 protocol version (LPV1) Status+0x00[[key_0, value_0], [key_1, value_1], ] Inform a peer of the senders current LES state. This message should be sent after the initial handshake and prior to any LES related messages. The following keys should be present in order to be accepted by a LES/1 node: (value types are noted after the key str Continue reading >>

Protocols - Godoc

Protocols - Godoc

import "github.com/ethereum/go-ethereum/p2p/protocols" Package protocols is an extension to p2p. It offers a user friendly simple way to definedevp2p subprotocols by abstracting away code standardly shared by protocols. * automate assigments of code indexes to messages* automate RLP decoding/encoding based on reflecting* provide the forever loop to read incoming messages* standardise error handling related to communication* standardised handshake negotiation* TODO: automatic generation of wire protocol specification for peers const ( ErrMsgTooLong = iota ErrDecode ErrWrite ErrInvalidMsgCode ErrInvalidMsgType ErrHandshake ErrNoHandler ErrHandler) error codes used by this protocol scheme type Error struct { Code int // contains filtered or unexported fields} Error implements the standard go error interface.Use: errorf(code, format, params ...interface{}) where description is given by code in errorToStringand details is fmt.Sprintf(format, params...) type Peer struct { * p2p . Peer // the p2p.Peer object representing the remote // contains filtered or unexported fields} Peer represents a remote peer or protocol instance that is running on a peer connection witha remote peer Drop disconnects a peer.TODO: may need to implement protocol drop only? don't want to kick off the peerif they are useful for other protocols func (p * Peer ) Handshake(ctx context . Context , hs interface{}, verify func(interface{}) error ) (rhs interface{}, err error ) Handshake negotiates a handshake on the peer connection* arguments * context* the local handshake to be sent to the remote peer* funcion to be called on the remote handshake (can be nil) * expects a remote handshake back of the same type* the dialing peer needs to send the handshake first and then waits for remote* the listening peer w Continue reading >>

Vp2p Wire Protocol

Vp2p Wire Protocol

Peer-to-peer communications between nodes running Ethereum/Whisper/&c. clients are designed to be governed by a simple wire-protocol making use of existing V technologies and standards such as RLP wherever practical. This document is intended to specify this protocol comprehensively. Vp2p nodes communicate by sending messages using RLPx, an encrypted and authenticated transport protocol. Peers are free to advertise and accept connections on any TCP ports they wish, however, a default port on which the connection may be listened and made will be 30303.Though TCP provides a connection-oriented medium, Vp2p nodes communicate in terms of packets.RLPx provides facilities to send and receive packets. For more information about RLPx, refer to the protocol specification . Vp2p nodes find peers through the RLPx discovery protocol DHT. Peer connections can also be initiated by supplyingthe endpoint of a peer to a client-specific RPC API. There are a number of different types of payload that may be encoded within the RLP. This ''type'' is always determined by the first entry of the RLP, interpreted as an integer. Vp2p is designed to support arbitrary sub-protocols (aka capabilities) over the basic wire protocol. Each sub-protocol is given as much of the message-ID space as it needs (all such protocols must statically specify how many message IDs they require). On connection and reception of the Hello message, both peers have equivalent information about what subprotocols they share (including versions) and are able to form consensus over the composition of message ID space. Message IDs are assumed to be compact from ID 0x10 onwards (0x00-0x10 is reserved for Vp2p messages) and given to each shared (equal-version, equal name) sub-protocol in alphabetic order. Sub-protocols that ar Continue reading >>

Ethereumscala

Ethereumscala

More than 3 years have passed since last update. ETHEthereum Qiita altcoin EthereumEthereum Project Ethereum Ethereum2015FrontierETH 20162FrontierHomestead Ethereum Project Ethereum Ethereum Yellow Paper Ethereum Ethereum Yellow PaperConclusion EthereumEthereum Diffie-HellmanMDCmodification detection code Ethereum EthereumFrontier100140 MacBook Pro10 proof of workmining Ethash ASICEthereum ProjectEthash CALL op codeLOG op code140LOG op codeBloom filterEthereum Yellow Paperoperational semantics 32256 LevelDBJNIWindowsLevelDBWindowsLevelDBBerkeley DB JE Windows Whisper SwarmBittorrent Winny2 Frontier Winny Ethereum ETH PoWEthereumVMEthereumVMEthereum segregated witness EthereumVMEthereumVMEthereum EthereumEthereumEthereum ProjectVM EthereumMerkle Patricia Tree EthereumEthereumVMMerkle Patricia Treeseg wit Ethereum Project EthereumKey ValueMerkle Patricia TreeVMvalidation 100 80VM EthereumMerkle Patricia Tree I/O EthereumFrontierLevelDBBerkeley DB JE key value Ethereum EthereumRLPxMDCmodification detection code Ethereum Continue reading >>

Introduction Swarm 0.2rc5 Documentation

Introduction Swarm 0.2rc5 Documentation

immutable, unforgeable, verifiable yet plausibly deniable storage no single point of failure, fault and attack resilience censorship resistance, universally accessible permanent public record efficient market driven pricing. tradeable trade off of memory, persistent storage, bandwidth efficient use of the blockchain by the swarm accounting protocol deposit-challenge based guaranteed storage [planned for POC 0.4 by Q2 2018] Swarm client is part of the Ethereum stack, the reference implementation is written in golang and found under the go-ethereum repository. Currently at POC (proof of concept) version 0.2 is running on all nodes. Swarm defines the bzz subprotocol running on the ethereum devp2p network. The bzz subprotocol is in flux, thespecification of the wire protocol is considered stable only with POC 0.4 expected in Q2 2018. The swarm of Swarm is the collection of nodes of the devp2p network each of which run the bzz protocol on the same network id. Swarm nodes are also connected to an ethereum blockchain.Nodes running the same network id are supposed to connect to the same blockchain.Such a swarm network is identified by its network id which is an arbitrary integer. Swarm allows for upload and disappear which means that any node can just upload content to the swarm andthen is allowed to go offline. As long as nodes do not drop out or become unavailable, the content will stillbe accessible due to the synchronization procedure in which nodes continuously pass along available data between each other. Uploaded content is not guaranteed to persist until storage insurance is implemented (expected in POC 0.4 by Q2 2018). All participating nodes should consider voluntary service with no formal obligation whatsoever and should be expected to delete content at their will. Continue reading >>

Ethereum Platform - Blockchain Powerhouse

Ethereum Platform - Blockchain Powerhouse

Ethereum is the next generation of blockchain since it is programmable. In the case of bitcoin operations users are given a set of predefined operations, but with Ethereum our team can create operations of any complexity. Therefore it serves as a platform for many decentralized applications of blockchain and not only limited to cryptocurrencies. In other words Ethereum has a whole programing platform on top of its cryptocurrency which is implemented in every client. The programs are called DApps or Decentralized Applications. Ethereum Client Architecture can be visualized like this. At the core of Ethereum is the Ethereum Virtual Machine (EVM) which can execute complex code modelled on existing programming languages such as JavaScript and Python. Peer-to-peer (P2P) wire-protocol network for routing and maintaining connections A copy of all transactions in the blockchain database Consensus on all clients(nodes) of the blockchain which includes mining, verifying and propagating blocks Maintenance of private or public keys which is encrypted in a key file, saved only in that client, the user is using. The keys are the ownership and also the identity in the contracts. The DApps, smart contracts, running on the Ethereum Virtual Machine, EVM. Transactions addressing contracts are triggering the execution of them on the EVM. The applications of Ethereum are unlimited. Smart contracts are examples of applications that run on Ethereum platform exactly as programmed without any possibility of downtime, censorship, fraud or third party interference. Few examples implemented are trade clearing and settlement, insurance claim processing, electronic medical records, personal health tracking, royalty distribution, autonomous electric vehicle charging stations, supply chain and trade Continue reading >>

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