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Ethereum Whisper Documentation

Whisperv5 - Godoc

Whisperv5 - Godoc

import "github.com/ethereum/go-ethereum/whisper/whisperv5" Package whisperv5 implements the Whisper protocol (version 5). Whisper combines aspects of both DHTs and datagram messaging systems (e.g. UDP).As such it may be likened and compared to both, not dissimilar to thematter/energy duality (apologies to physicists for the blatant abuse of afundamental and beautiful natural principle). Whisper is a pure identity-based messaging system. Whisper provides a low-level(non-application-specific) but easily-accessible API without being based uponor prejudiced by the low-level hardware attributes and characteristics,particularly the notion of singular endpoints. const ( EnvelopeVersion = uint64 (0) ProtocolVersion = uint64 (5) ProtocolVersionStr = "5.0" ProtocolName = "shh" NumberOfMessageCodes = 64 TopicLength = 4 AESNonceLength = 12 MaxMessageSize = uint32 (10 * 1024 * 1024) // maximum accepted size of a message. DefaultMaxMessageSize = uint32 (1024 * 1024) DefaultMinimumPoW = 0.2 DefaultTTL = 50 // seconds SynchAllowance = 10 // seconds) var ( ErrSymAsym = errors . New ("specify either a symmetric or an asymmetric key") ErrInvalidSymmetricKey = errors . New ("invalid symmetric key") ErrInvalidPublicKey = errors . New ("invalid public key") ErrInvalidSigningPubKey = errors . New ("invalid signing public key") ErrTooLowPoW = errors . New ("message rejected, PoW too low") ErrNoTopics = errors . New ("missing topic(s)")) func BytesToUintBigEndian(b [] byte ) (res uint64 ) BytesToUintBigEndian converts the slice to 64-bit unsigned integer. func GenerateRandomID() (id string , err error ) GenerateRandomID generates a random string, which is then returned to be used as a key id func NewSentMessage(params * MessageParams ) (*sentMessage, error ) NewSentMessage creates and initiali Continue reading >>

Getting Started With Embark Framework

Getting Started With Embark Framework

Tutorials and jobs for Ethereum enthusiasts. In the previous articles we saw all the basics of Ethereum smart contracts development with Solidity. We used Ethereum Wallet and it was great! We were able to have a simple and easy to setup small dev environment. As you figured out it was nice for getting started but what if we want to go deeper? We want to write bigger applications, be able to use multiple source files. Write tests, debug, use a versioning system, deploy multiple contracts at once ect To go deeper well use the Embark Framework . Embark Framework is easy to get started with and has a lot of features: Automatically deploy contracts and make them available in your JS code. Embark watches for changes, and if you update a contract, Embark will automatically redeploy the contracts (if needed) and the dapp. Contracts are available in JS with Promises. Do Test Driven Development with Contracts using Javascript. Keep track of deployed contracts; deploy only when truly needed. Manage different chains (e.g testnet, private net, livenet) Easily manage complex systems of interdependent contracts. Easily Store & Retrieve Data on the DApp through EmbarkJS. Including uploading and retrieving files. Deploy the full application to IPFS or Swarm. Decentralized Communication (Whisper, Orbit) Easily send/receive messages through channels in P2P through Whisper or Orbit. Integrate with any web technology including React, Foundation, etc.. Use any build pipeline or tool you wish, including grunt, gulp and webpack. On your terminal, the embark dashboard will take life, it should look like this: The list of your deployed contracts and there addresses, in the Embark demonstration sample, there is only one contract: Simple Storage that have a simple mission: storing one value and m Continue reading >>

An Experiment With Whisper

An Experiment With Whisper

Weve been looking at Whisper, a messaging system that runs on top of the Vp2p peer-to-peer network. The same network that is run by all Ethereum nodes. It has a number of characteristics that, in time, could make it the standard component that developers reach for when they need to add messaging to their code. Being based on a peer-to-peer network, you do not need any servers. When youre developing an app, that is a big win. No contracts with cloud providers, no server infrastructure to maintain. Whispers use of encryption and a smart routing mechanism ensure that both the contents of messages and the metadata (who talks to whom) are kept private. This is not only a big win for the users, but also for the developers. Not having access to the data of their users means less liability. Developers cannot accidentally leak the data, they cannot be coerced to hand it over to a third party and they cannot censor it. We would like to see how far we could get in using Whisper in a normal development setting. So we decided to start a prototype of a chat app using Whisper. We ended up with the following architecture: --------------------------------| Our Simple Chat App || | -----------------| ----------------------- | | Ethereum Node || | The Shhwift Library | | JSON-RPC | || | | <-----------------> | | ----------------------- | | |-------------------------------- ----------------- We start an Ethereum node (in this case Geth ) and connect to it using its JSON-RPC interface . For most of our testing we ran the ethereum node on a computer, and connected to it from the phone. We also attempted to run an Ethereum node on the phone with limited success. We created a library we called Shhwift that wraps the JSON-RPC methods for Whisper in Swift, so that we could easily call them from Continue reading >>

Whisper Overview Ethereum/go-ethereum Wiki Github

Whisper Overview Ethereum/go-ethereum Wiki Github

Whisper is a pure identity-based messaging system. Whisper provides a simple low-level API without being based upon or influenced by the low-level hardware attributes and characteristics. Peer-to-peer communication between the nodes of Whisper network uses the underlying Vp2p Wire Protocol . Whisper was not designed to provide a connection-oriented system, nor for simply delivering data between a pair of particular network endpoints. However, this might be necessary in some very specific cases (e.g. delivering the expired messages in case they were missed), and Whisper protocol will accommodate for that. Whisper is designed for easy and efficient broadcasting, and also for low-level asynchronous communications. It is designed to be a building block in next generation of unstoppable Apps. It was designed to provide resilience and privacy at considerable expense. At its most secure mode of operation, Whisper can theoretically deliver 100% darkness. Whisper should also allow the users to configure the level of privacy (how much information it leaks concerning the App content and ultimately, user activities) as a trade-off for performance. Basically, all Whisper messages are supposed to be sent to every Whisper node. In order to prevent a DDoS attack, proof-of-work (PoW) algorithm is used. Messages will be processed (and forwarded further) only if their PoW exceeds a certain threshold, otherwise they will be dropped. All Whisper messages are encrypted and then sent via underlying Vp2p Protocol, which in turn uses its own encryption, on top of Whisper encryption. Every Whisper message must be encrypted either symmetrically or asymmetrically. Messages could be decrypted by anyone who possesses the corresponding key. In previous versions unencrypted messages were allowed, but Continue reading >>

Status Developer Documentation

Status Developer Documentation

Welcome to the Status API! Tread carefully, for you tread on the dreams of a better web. Status allows users to interact with a wide array of Decentralized Applications (DApps) using the same intuitive chat interface (it also does a bunch of other things, but well focus on this aspect for now). In the near future, Status users will be able to have group chats where most of the participants are DApp chatbots. All DApp developers will benefit from this synergy, because a common chat interface for multiple DApps makes using your specific DApp more convenient, and effectively makes your DApp more powerful by giving it access to potentially far wider and more powerful network effects. In this guide, well explore how you can use the Status API to develop your DApp and create custom commands for your users that will work in a beautifully-intuitive, mobile context. As a result of developing on Status, youll have a DApp that your users can access on MetaMask, Mist, and Status. Its really worth emphasising that using Status brings with it access to mobile users with native mobile commands. With little extra developer time invested, youll gain a mobile DApp. If you already have a DApp with a web interface, then this will be the quickest Quickstart ever (trademark pending). Simply open Status, navigate to Console, hit the @browse command and type in the url where your DApp is running. Voila! Users in Status can already see your DApp and interact with it (on the Ropsten Test Network). Make some mobile optimizations of your own and youre away. That is the power of decentralized, web3 technologies. Awesome, right? OK, but what if (a) I dont have a DApp but want to learn how to build one on Status, or (b) I want to use this awesome API to make the most of an awesome, native mobile UX, Continue reading >>

Javascript Api | Ethereum Builder's Guide

Javascript Api | Ethereum Builder's Guide

To make your app work with on Ethereum, you can use the web3 object provided by the web3.js library . Under the hood it communicates to a local node through RPC calls . web3.js works with AlethZero, geth and Mist, and also in an external browser if one of the former nodes are running locally. web3 contains the eth object - web3.eth (for specifically Ethereum blockchain interactions) and the shh object - web3.shh (for Whisper interaction). Over time we'll introduce other objects for each of the other web3 protocols. As this API is designed to work with a local RPC node and all its functions are by default use synchronous HTTP requests. If you want to make asynchronous request, you can pass an optional callback as the last parameter to most functions.All callbacks are using an error first callback style: web3.eth.getBlock(48, function(error, result){ if(!error) console.log(result) else console.error(error);}) You will always get a BigNumber object for balance values as JavaScript is not able to handle big numbers correctly.Look at the following examples: "101010100324325345346456456456456456456"// "101010100324325345346456456456456456456"101010100324325345346456456456456456456// 1.0101010032432535e+38 web3.js depends on the BigNumber Library and adds it automatically. var balance = new BigNumber('131242344353464564564574574567456');// or var balance = web3.eth.getBalance(someAddress);balance.plus(21).toString(10); // toString(10) converts it to a number string// "131242344353464564564574574567477" The next example wouldn't work as we have more than 20 floating points, therefore it is recommended to keep you balance always in wei and only transform it to other units when presenting to the user: var balance = new BigNumber('13124.234435346456466666457455567456');balance.pl Continue reading >>

What Are The Modules?

What Are The Modules?

evmjit: library for the EVM just-in-time compiler libethash: ethash mining POW algorithm implementation libethash-cl: ethash mining code for GPU mining (OpenCL) libethashseal: generic wrapper around the POW block seal engine. Also contains the genesis states for all ethash-based chains. libethcore: collection of core data structures and concepts libethereum: main consensus engine (minus EVM). Includes the State and BlockChain classes. libevm: Expanse Virtual Machine implementation (interpreter). libevmasm: EVM assembly tools, also contains the optimizer. libevmcore: elementary data structures of the EVM, opcodes, gas costs, ... liblll: Low-level LISP-like Language compiler & assembler. libnatspec: natspec script evaluator (confirmation messages) libweb3core - Web3 core libraries, networking, encoding, decoding, basic data structures. libdevcore: data structures, utilities, rlp, trie, memory db libdevcrypto: crypto primitives. Depends on libsecp256k1 and libcrypto++. libp2p: core peer to peer networking implementation (excluding specific sub-protocols) Continue reading >>

Embark - Npm

Embark - Npm

Embark is a framework that allows you to easily develop and deploy Decentralized Applications (DApps). A Decentralized Application is a serverless html5 application that uses one or more decentralized technologies. Embark currently integrates with EVM blockchains (Ethereum), Decentralized Storages (IPFS), and Decentralized communication platforms (Whisper and Orbit). Swarm is supported for deployment. Automatically deploy contracts and make them available in your JS code. Embark watches for changes, and if you update a contract, Embark will automatically redeploy the contracts (if needed) and the dapp. Contracts are available in JS with Promises. Do Test Driven Development with Contracts using Javascript. Keep track of deployed contracts; deploy only when truly needed. Manage different chains (e.g testnet, private net, livenet) Easily manage complex systems of interdependent contracts. Easily Store & Retrieve Data on the DApp through EmbarkJS. Including uploading and retrieving files. Deploy the full application to IPFS or Swarm. Decentralized Communication (Whisper, Orbit) Easily send/receive messages through channels in P2P through Whisper or Orbit. Integrate with any web technology including React, Foundation, etc.. Use any build pipeline or tool you wish, including grunt, gulp and webpack. Embark's npm package has changed from embark-framework to embark, this sometimes can create conflicts. To update first uninstall embark-framework 1 to avoid any conflicts. npm uninstall -g embark-framework then npm install -g embark You can easily create a sample working DApp with the following: You can run a REAL ethereum node for development purposes: Alternatively, to use an ethereum rpc simulator simply run: By default Embark blockchain will mine a minimum amount of ether and Continue reading >>

Truffle Suite - Your Ethereum Swiss Army Knife

Truffle Suite - Your Ethereum Swiss Army Knife

Truffle is the most popular development framework for Ethereum with a mission to make your life a whole lot easier. Dont know where to start? Get yourself a Truffle Box! Built-in smart contract compilation, linking, deployment and binary management Truffle takes care of managing your contract artifacts so you dont have to. Includes support for custom deployments, library linking and complex Ethereum applications. Automated contract testing for rapid development Bring your dapp development to the 21st century. Write automated tests for your contracts in both JavaScript and Solidity, and get your contracts developed quickly. Scriptable deployment & migrations framework Write simple, manageable deployment scripts that acknowledge your application will change over time. Foster your dapps evolution and ensure you can maintain your contracts far into the future. Network management for deploying to both public & private networks Dont manage network artifacts ever again. Let Truffle do it for you, and put your focus on dapp development where it belongs. Pull in hundreds of smart contract dependencies from NPM and EthPM to have your code stand on the shoulders of giants. Interactive console for direct contract communication Use Truffle to save time and talk to your contracts via an interactive console, which includes access to all your built contracts and all available Truffle commands. External script runner that executes scripts within a Truffle environment Use Truffle to bootstrap your contracts and run a network-aware script, without hassle. Whether youre compiling contracts or running unit tests, Truffle includes clever optimizations to ensure you only compile what you have to and your tests run as quickly as possible. When used along with Ganache , you can develop your da Continue reading >>

Whisper Overview Parity Tech Documentation

Whisper Overview Parity Tech Documentation

var shh = web3.shh;var appName = "My silly app!";var myName = "Gav Would";var myIdentity = shh.newIdentity();shh.post({ "from": myIdentity, "topic": [ web3.fromAscii(appName) ], "payload": [ web3.fromAscii(myName), web3.fromAscii("What is your name?") ], "ttl": 100, "priority": 1000});var replyWatch = shh.watch({ "topic": [ web3.fromAscii(appName), myIdentity ], "to": myIdentity});// could be "topic": [ web3.fromAscii(appName), null ] if we wanted to filter all such// messages for this app, but we'd be unable to read the contents.replyWatch.arrived(function(m){ // new message m console.log("Reply from " + web3.toAscii(m.payload) + " whose address is " + m.from);});var broadcastWatch = shh.watch({ "topic": [ web3.fromAscii(appName) ] });broadcastWatch.arrived(function(m){ if (m.from != myIdentity) { // new message m: someone's asking for our name. Let's tell them. var broadcaster = web3.toAscii(m.payload).substr(0, 32); console.log("Broadcast from " + broadcaster + "; replying to tell them our name."); shh.post({ "from": eth.key, "to": m.from, "topics": [ eth.fromAscii(appName), m.from ], "payload": [ eth.fromAscii(myName) ], "ttl": 2, "priority": 500 }); }}); post takes a JSON object containing four key parameters: shh.post({ "topic": t, "payload": p, "ttl": ttl, "workToProve": work }); topic, provided as either a list of, or a single, arbitrary data items that are used to encode the abstract topic of this message, later used to filter messages for those that are of interest; payload, provided similarly to topic but left as an unformatted byte array provides the data to be sent. ttl is a time for the message to live on the network, specified in seconds. This defaults to 50. work is the amount of priority you want the packet to have on the network. It is specified in mi Continue reading >>

Learn Why Blockchain Technology Has The Potential To Transform Everyindustry

Learn Why Blockchain Technology Has The Potential To Transform Everyindustry

Learn why blockchain technology has the potential to transform everyindustry Emerging blockchain solutions point to a future of dependable decentralized trustworthy transactions thats withinreach One of the lessons Ive learned from writing about blockchain is that you must provide a bit of an introduction on the technology otherwise, Ill lose 80% of the audience. This is understandable given the complexity of blockchain technology and the confusion around different platforms, networks, tokens, and applications. Much of the publics attention is focused on the rise and fall of cryptocurrency values and the huge amount of dollars flooding into the space. This is a shame because under the hood of blockchain is some impressive architecture and vision that promises to create a huge wave of innovation and, along with it, a fair bit of disruption. Before I get there, and in the interest of the first rule of blockchain, here are some key points about cryptocurrency and blockchain to serve as a base. Cryptocurrencies are separate from blockchain technology. The first is a digital representation of perceived value; the second is a method for distributed transaction processing and storage. At the core of a blockchain platform lies a distributed transaction processing engine that validates and cryptographically seals transactions. Blockchains consist of sets of transactions that are sealed within a block using cryptographic algorithms. Successive blocks are linked to the preceding blocks by using hash values such that there is a sequential chain that is largely permanent and immutable. Blockchain networks are comprised of near identical nodes operating in a distributed but independent manner. The network of nodes is used to validate the transactions and encapsulate them within bloc Continue reading >>

How To Buy Bitcoin On Stock Market Ethereum Whisper Swarm

How To Buy Bitcoin On Stock Market Ethereum Whisper Swarm

How To Buy Bitcoin On Stock Market Ethereum Whisper Swarm I was hoping Top 5 Cryptocurrencies To Invest In Ethereum Dapp Tutorial veteran ETH folks could help answer some of the following questions. That's what we want from cryptos in general. Obviously it's nothing like devoting YEARS to a project that will never turn you a profit, but it's still a selfless investment of time. It has been effectively deprecated due to the numerous critical-severity bugs found by Zeppelin. For golang, the abigen executable in go-ethereum provides go packages for interfacing with contracts. SlideShare Explore Search You. With that said, I've heard ETH is difficult to program in. Blockchain networks are comprised of near identical nodes operating in a distributed but independent manner. The main insight of Ethereum is that it's impossible to define a "do everything" blockchain at the consensus level, and that trying to design in every possible feature at that level only How Many Gh Is 1 Bitcoin Cant Find Any Ethereum Minecraft additional risk. There are several alternatives in existence already, albeit less popular. Register for Consensus today! You probably also want a nice way to play around with new ideas. Run a local ethereum node for testing and development with Ganache previously called ethereumjs-testrpc. Major Fortune 50 companies are already demanding public Wix Cryptocurrency Can You Mine Ethereum With Gtx 970 track and trace use cases for which they are using the Viant platform to build their solutions. The crypto universe is booming, and finance is one of its hottest segments. For the most part, the things you've mentioned I like to categorize in the big bucket of "consumer protection and risk mitigation". It's the ultimate way let others develop Coinbase Litecoin Segwit Or L Continue reading >>

Getting Up To Speed Onethereum

Getting Up To Speed Onethereum

Go from zero to without all the nonsense. You want to have a deep working understanding of Ethereum and the related ecosystem. You understand the concept of a blockchain and how Bitcoin uses it to create a trustless digital currency. No? Watch this short video or watch this long video . Hint, you should probably watch the long one. Youre a professional software engineer. Seriously, I mean, nontrivial amounts of real-world software engineering experience. Understanding systems/architecture/math is a learning efficiency multiplier. Like a week of your free time. I told you were skipping the nonsense. You understand the basic concept of a merkle tree and how it can be used to quickly verify information correctness. Note: you dont need to read the whitepapers, but you need to understand them. But it turns out that reading them is the fastest way to understand them. I recommend reading the entirety of this post, absorbing the contents at a high level, and then diving into each link individually, over the course of a few days. Youll be surprised at how little of this technology is magic (read: none of it), despite the severe case of buzzword-itis the ecosystem has. Everyone is building off of the shoulders of giants; if you make a living as a professional software engineer you have the ability to understand all of these projects and technologies at a deep level. Just dont get distracted by the bullshit. Ethereum is a distributed computer; each node in the network executes some bytecode (hint: Smart Contracts), and then stores the resulting state in a blockchain. Due to the properties of the blockchain representing application state, this results in applications that run exactly as programmed without any possibility of downtime, censorship, fraud or third party interference. Continue reading >>

Whisper V5 Rpc Api Ethereum/go-ethereum Wiki Github

Whisper V5 Rpc Api Ethereum/go-ethereum Wiki Github

Object - diagnostic information with the following properties: minPow - Number: current minimum PoW requirement. maxMessageSize - Float: current messgae size limit in bytes. memory - Number: Memory size of the floating messages in bytes. messages - Number: Number of floating messages. // Requestcurl -X POST --data '{"jsonrpc":"2.0","method":"shh_info","params":[],"id":1}'// Result{ "id":1, "jsonrpc": "2.0", "result": { "minPow": 12.5, "maxMessageSize": 20000, "memory": 10000, "messages": 20, }} Sets the maximal message size allowed by this node.Incoming and outgoing messages with a larger size will be rejected.Whisper message size can never exceed the limit imposed by the underlying P2P protocol (10 Mb). Boolean: (true) on success and an error on failure. // Requestcurl -X POST --data '{"jsonrpc":"2.0","method":"shh_setMaxMessageSize","params":[234567],"id":1}'// Result{ "id":1, "jsonrpc": "2.0", "result": true} Sets the minimal PoW required by this node. This experimental function was introduced for the future dynamic adjustment of PoW requirement. If the node is overwhelmed with messages, it should raise the PoW requirement and notify the peers. The new value should be set relative to the old value (e.g. double). The old value could be obtained via shh_info call. Note This function is currently experimental. Boolean: true on success and an error on failure. // Requestcurl -X POST --data '{"jsonrpc":"2.0","method":"shh_setMinPoW","params":[12.3],"id":1}'// Result{ "id":1, "jsonrpc": "2.0", "result": true} Marks specific peer trusted, which will allow it to send historic (expired) messages. Note This function is not adding new nodes, the node needs to exists as a peer. Boolean (true) on success and an error on failure. // Requestcurl -X POST --data '{"jsonrpc":"2.0","m Continue reading >>

Devcon 3 Report: Day 4 P2p Tech

Devcon 3 Report: Day 4 P2p Tech

Todays sessions covered a lot of secure messaging (Whisper / PSS), some swarm, and a couple of sessions on real world supply chain / logistics applications Whisper: Achieving Darkness Vlad Gluhovsky Imagine a world where defensive technology always won. World would live in harmony. Lots of harmony and liberty for all Want to help achieve darkness with whisper. Whisper is a messaging system designed to deliver darkness at high cost. Darkness is when no meta-information has been leaked. Plausible deniability. Is an integral part of Ethereum. Off chain. The underlying Ethereum communication protocol takes care of delivery. It is a gossip protocol. Every message is delivered to every node. Message is forwarded on, node cant decrypt it, passes it on. When the message does receive a message that is for them that they decrypt, the node still passes it on so that no one knows it was the final recipient. Ephemeral identities. Decentralised. Built in steganography. Darkness Is high latency, high traffic, high processor load, high memory usage. Need to try and decrypt messages even if they arent addressed to you (is the only way to find out if it is to you). The topic is 4 bytes of arbitrary data. Used for probablistic message filtering. Will be used for routing in version 6. Topic collisions are expected and required for plausible deniability. Is just there to help you get a subset. But you dont want to reduce darkness too much. Sender: maintaining noise by sending random data sometimes. So that metadata isnt leaked by only sending messages when it is a real message. Can do symmetric and asymmetric encryption. Whisper is tech agnostic. Can use on any network. Need to pad messages with random data to not leak metadata. Additionally you can use steganography to hide messages in th Continue reading >>

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