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1  Alternate cryptocurrencies / Announcements (Altcoins) / ⚡⭐⭐ [ANN] DISPATCH LABS – Scalable smart-contract platform for infinite data on: April 09, 2018, 06:01:40 PM




Website  |  Whitepaper  |  Lightpaper  |  Chat


Dispatch is a new distributed ledger protocol built on three core principles

The Dispatch protocol is scalable.
  Using our own DAPoS consensus, Dispatch achieves high transaction throughput, with no transaction fees.

Dispatch is backwards-compatible with Ethereum smart-contracts and the Ethereum Virtual Machine (EVM).
  Dispatch uses a modified version of the EVM, and is compatible with most Dapps currently under development.

Dispatch handles lots of data.
  Most business logic involves data too big to fit in a shared ledger. Dispatch extends the functionality of Ethereum smart-contracts to support big data access off-chain, what we now call artifacts.

Dispatch maximizes the customizable properties of Dapps on our chain, and will become the de-facto platform for Dapps.

Dispatch does not give developers strict rules. Encoding data as artifacts with smart-contracts allows developers to write their own logic per application, including their cryptography, data structures, access models, and more. Dispatch will allow storage and access to data, as well as integrated off-chain computation.

Storage and computation are the core elements of the Dispatch protocol, in order to be scalable and fast enough to handle the needs of any business.




Scalability
Dispatch enables companies to build data-intensive business logic on a public ledger without sacrificing speed or security. The Dispatch protocol uses Delegated Asynchronous Proof of Stake (DAPoS), a novel consensus algorithm, which handles orders of magnitude more transactions than most blockchains. DAPoS transactions are validated by elected delegates and recorded by elected learners. Valid transactions are gossipped. Invalid transactions are dropped. Unlike regular blockchains, where the tx/sec is bounded by tx/block x blocks/sec, DAPoS is bound by the hardware of the delegates and how fast they can validate transactions.

Delegated Asynchronous Proof of Stake
Dispatch enables companies to build data-intensive business logic on a public ledger without sacrificing speed or security. The Dispatch ledger is built with a new form of consensus called Delegated Asynchronous Proof-of-Stake (DAPoS) for both business and moral reasons. By migrating to a DAPoS mode of transaction validation, the costs associated with writing transactions to the blockchain fall dramatically. Transaction times can be brought down to nearly a single second, and unlike regular blockchains, where the tx/sec is bound by tx/block x blocks/sec, DAPoS is bound by the hardware of the delegates and how fast they can validate transactions. High throughput and low costs of DAPoS make the usability of Dapps much more practical for businesses. Additionally, DAPoS uses significantly less energy than traditional consensus methods.

The Dispatch Virtual Machine (DVM)
The Dispatch protocol is backwards compatible with Ethereum smart-contracts. The Dispatch Virtual Machine (DVM), is a modification of the EVM, built to support access to off-chain artifacts. The DVM allows the creation and execution of stateful programs using the ledger’s shared state, just like the EVM. The DVM adds artifact primitives and read/write opcodes to enable smart-contracts that support interactions with off-chain data. The DVM enables Dapp developers to build data-intensive business logic into smart-contracts.




The Dispatch Artifact Network
Off-chain data is stored with our network of farmers in the Dispatch Artifact Network (DAN). The DAN operates on a number of protocols like Kademlia DHT for Artifact discovery, Proof-of Replication (PoRep) to resist Sybil attacks, Proof-of-Retrievability (PoR) to ensure availability of Artifacts, and Make-it-Happen (MiH) protocol for efficient transfers of Artifacts.



Artifacts
Dispatch introduces a new class of information: Artifacts, stored in the DAN. The DAN is composed of uploaders, farmers, and downloaders, each with an identical copy of the shared ledger, but holding a various number of different artifacts. Below is a flow diagram of an Artifact’s life cycle.





The flow of a Dispatch Artifact starts when the uploader publishes a smart-contract containing a hash of the Artifact, and rules for accessing it (1). Hashing the file reduces the amount of data written to the shared ledger, and keeps the Artifact itself unknown to other nodes in the network. Rules for accessing the Artifact can be based on time, price, user group, oracles, etc. Once the smart contract is published to the shared ledger (2), anyone can request the Artifact from the uploader. Downloaders will know they received the right Artifact when the hash of what they received matches the one in the shared ledger.

Uploaders pay farmers to serve encrypted copies of their Artifacts (3) to service more downloaders, and to mitigate downtime. Farmers are compensated for their storage as well as their bandwidth. When a downloader wants an Artifact (4), they can check their Kademlia DHT (5) to find the closest available farmer (6). When downloading an encrypted Artifact from a farmer (7), the downloader will still need the much smaller encryption key from the uploader.




Specs:

DAPoS Consensus

Token name: Divvy

Tx speed: Incredibly fast (10,000+ transactions per-second in normal conditions. 100,000 TPS in perfect conditions)

No transaction fees




Roadmap:





Tokenomics:
Dispatch Tokens are the core currency of the Dispatch Network. They are the underlying economic value unit which allows interactions between Farmers, Uploaders, and Downloaders. 18bn Dispatch tokens will be minted.



Building on Dispatch
Several large projects are already building to transition to Dispatch at launch. As Dispatch’s DVM is backwards compatible with EVM, developers can start building their proof-of-concept on Ethereum before the mainnet launch of Dispatch.

The extended development roadmap includes an Ethereum to Dispatch smart-contract transfer tool. The tool will move the contract and its state to the more scalable Dispatch chain in a hard-fork fashion. Please contact our team if you are interested in building on or transitioning to Dispatch.




Official Channels:






Dev Evangelist Program
Dispatch is currently working on a developer evangelist program, details will be available shortly.

The Dev Evangelist Program will be announced here as well as on our community channels. First availability will go to members of our Telegram and Discord channels at the time of the announcement.



Team






Advisors






Media



1. Forbes  |  2. Inc.  |  3. Huffington Post  |  4. Entrepreneur  |  5. Crypto Coins News  |  6. NuWire Investor  |  7. The Next Web  |  8. The Next Web

2  Other / Beginners & Help / A Quick Classification of Types of Cryptocurrency Consensus Algorithms on: February 14, 2018, 02:26:14 AM
Reposting this for newer member education.  Hope this is useful.

Proof-of-Work (PoW)
Popular implementations: Bitcoin, Ethereum, Litecoin, Dogecoin, (Most of them)
Pros: We know it works
Cons: Slow throughput; killing the planet

Proof of Work was the first blockchain consensus algorithm. Devised by Satoshi Nakamoto for use in the Bitcoin blockchain, we have PoW to thank for the massive mining operations and power consumption we see around the world. We know it works (which is a lot more that we can say for many other consensus algorithms), but at this stage in the game it’s starting to be considered a legacy technology. Even Ethereum is migrating away from PoW for more energy and economically efficient PoS. With so many new alternatives, it’s hard to see why a new blockchain would use PoW.
In PoW, miners solve hard, useless problems to create blocks. PoW runs on a system of “the longest chain wins.” So, assuming most miners are working on the same chain, that one will grow fastest will be the longest and most trustworthy. Hence Bitcoin is safe as long as more than 50% of the work being put in by miners is honest.

Proof-of-Stake (PoS) 
Popular implementations: Decred, Ethereum (soon), Peercoin
Pros: Attacks more expensive; More decentralized; Energy efficient
Cons: Nothing at Stake

In PoS, the blocks aren’t created by miners doing work, but by minters staking their tokens to “bet” on which blocks are valid. In the case of a fork, minters spend their tokens voting on which fork to support. Assuming most people vote on the correct fork, validators who voted on the wrong fork would “lose their stake” in the correct one.
The common argument against proof-of-stake is the Nothing at Stake problem. The concern is that since it costs validators almost no computational power to support a fork unlike PoW, validators could vote for both sides of every fork that happens. Forks in PoS could then be much more common than in PoW, which some people worry could harm the credibility of the currency.

Delegated Proof-of-Stake (DPoS)
Popular Implementations: Steemit, EOS, BitShares
Pros: Cheap transactions; scalable; energy efficient
Cons: Partially centralized

DPoS is the brain-child of Daniel Larimer, and is actually very different from PoS. In DPoS, token hodlers don’t vote on the validity of the blocks themselves, but vote to elect delegates to do the validation on their behalf. There are generally between 21–100 elected delegates in a DPoS system. The delegates are shuffled periodically and given an order to deliver their blocks in. Having few delegates allows them to organize themselves efficiently and create designated time slots for each delegate to publish their block. If delegates continually miss their blocks or publish invalid transactions, the stakers vote them out and replace them with a better delegate.
In DPoS, miners can collaborate to make blocks instead of competing like in PoW and PoS. By partially centralizing the creation of blocks, DPoS is able to run orders of magnitude faster than most other consensus algorithms. EOS is set to be the first blockchain with block times < 1 second! A little quicker than bitcoin’s 10 minute block times.

Proof-of-Authority (PoA)
Popular Implementations: POA.Network, Ethereum Kovan testnet
Pros: High throughput; scalable
Cons: Centralized system

Proof-of-Authority is a consensus algorithm where transactions are validated by approved accounts, kind of like the “admins” of the system. These accounts are the authority that other nodes receive their truth from. PoA has high throughput, and is optimized for private networks. You’re unlikely to see PoA running on a public chain due to its centralized nature.

Proof-of-Weight (PoWeight)
Popular Implementations: Algorand, Filecoin, Chia
Pros: Customizable; scalable
Cons: Incentivization can be a challenge

Proof-of-Weight is a broad classification of consensus algorithms based around the Algorand consensus model. The general idea is that where in PoS, your percentage of tokens owned in the network represents your probability of “discovering” the next block, in a PoWeight system, some other relatively weighted value is used. Concrete example: Filecoin’s Proof-of-Spacetime is weighted on how much IPFS data you’re storing. Other systems could include weights for things like Proof-of-Reputation.

Byzantine Fault Tolerance (BFT) 
Popular Implementations: Hyperledger, Stellar, Dispatch, and Ripple
Pros: High throughput; low cost; scalable
Cons: Semi-trusted

There’s this classic problem is distributed computing that’s usually explained with Byzantine generals. The problem is that several Byzantine generals and their respective portions of the Byzantine army and have surrounded a city. They must decide in unison whether or not to attack. If some generals attack without the others, their siege will end in tragedy. The generals are usually separated by distance and have to pass messages to communicate. Several cryptocurrency protocols use some version of BFT to come to consensus, each with their own pros and cons:

Practical Byzantine Fault Tolerance (PBFT): One of the first solutions to this problem was coined Practical Byzantine Fault Tolerance. Currently in use by Hyperledger Fabric, with few (< 20, after that things get a little ) pre-selected generals PBFT runs incredibly efficiently. Pros: High transaction throughput Cons: Centralized/permissioned
Federated Byzantine Agreement (FBA): FBA is another class of solutions to the Byzantine generals problem used by currencies like Stellar and Ripple. The general idea (heh), is that every Byzantine general, responsible for their own chain, sorts messages as they come in to establish truth. In Ripple the generals (validators) are pre-selected by the Ripple foundation. In Stellar, anyone can be a validator so you choose which validators to trust.

For its incredible throughput, low transaction cost, and network scalability, I believe the FBA class of consensus algorithms are the best we’ve discovered for distributed consensus.

Directed Acyclic Graphs (DAGs)
Popular Implementations: Iota, Hashgraph, Raiblocks/Nano
Pros: Network Scalability; low cost
Cons: Depends on implementation

DAGs are a form of consensus that doesn’t use the blockchain data structure and handles transactions mostly asynchronously. The big pro is theoretically infinite transactions per second, but DAGs have strengths and weaknesses like any other consensus.

Tangle: Tangle is the DAG consensus algorithm used by Iota. In order to send an Iota transaction, you need to validate two previous transactions you’re received. The two-for-one, pay-it-forward consensus strengthens the validity of transactions the more transactions are added to the Tangle. Because the consensus is established by the transactions, theoretically, if someone can generate 1/3 of the transactions they could convince the rest of the network their invalid transactions are valid. Until there’s enough transaction volume that creating 1/3rd of the volume becomes unfeasible, Iota is sort-of “double-checking” all of the network’s transactions on a centralized node called “The Coordinator”. Iota says The Coordinator works like training wheels for the system and will be removed once the Tangle is big enough.

Hashgraph: Hashgraph is a gossip-protocol consensus developed by Leemon Baird. Nodes share their known transactions with other nodes at random so eventually, all the transactions are gossiped around to all of the nodes. Hashgraph is really fast (250,000+ transactions per second) but isn’t resistant to Sybil attacks. So Hashgraph is a great option for private networks, but you’re not going to see it implemented in a public network like Ethereum or Dispatch anytime soon.

Block-lattice: Nano (formerly Raiblocks) runs with a twist on the blockchain called a Block-lattice. The Block-lattice is a structure where every user (address) gets their own chain that only they can write to, and everyone holds a copy of all of the chains. Every transaction is broken down into both a send block on the sender’s chain and a receive block on the receiving party’s chain. The Block-lattice seems almost too simple to work, but it’s already out there running in the wild. The unique structure does leave the Block-lattice open to some unique attack vectors like the Penny-spend attack, where attackers inflate the number of chains node must keep track of by sending negligible amounts to a wide array of empty wallets.

SPECTRE: Serialization of Proof-of-work Events: Confirming Transactions via
Recursive Elections, better known as SPECTRE, is a proposed Bitcoin scaling solution that utilizes a combination of PoW and DAGs to reach scalable consensus. In SPECTRE, the blocks are mined pointing to multiple parents, not just one, so the network could potentially handle multiple blocks per second. Mining a block pointing to some parent blocks supports those blocks validity. Compared to PoW’s “longest chain wins”, SPECTRE uses something like “blocks with the most childen win.” SPECTRE hasn’t been battle-tested in the wild yet, and new attack vectors are likely to emerge, but it feels like a very clever potential way to fix Bitcoin.

Did I miss your favorite algorithm? Feedback is always appreciated!
3  Economy / Trading Discussion / Checking crypto prices on: February 12, 2018, 08:06:10 AM
94% of those who own crypto currencies check them daily. I'm interested to see who often most prople here check.
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