alholm/akhcoin

Simple blockchain/cryptocurrency implementation with DPOS consensus mechanism

AkhCoin

Simple blockchain/cryptocurrency implementation with DPOS consensus mechanism

Background

Original goal of this project is educational: understand what challenges blockchain developer faces and ways to solve them.
However final result is intended to be fully functional "production ready" software, maybe will even become valuable cryptocurrency 😃
Check out the wiki for detailed problems and solutions description.

Roadmap

• see Project
• Refacoring

Installation

Binaries

#TBD

From sources

Pre-requisits: go 1.9+

> go get -u github.com/alholm/akhcoin

Docker image

#TBD

Usage

> $GOPATH/bin/akhcoin [-p <port>] [-k <key_file_path>] #Defaults: port = 9765, key_file_path = ./id_rsa

Then follow CLI instructions

License

MIT

akhcoin's Issues

Refactoring

1) Generalise Transaction and Vote - too much similarity [Done]
2) Generalise StreamHandler implementations

Implement delegates shuffling

Consensus: Implement simple election

Add produced block verification from consensus perspective

Check wether block was produced by elected node and at required timeslot.
Think of punishment for violater

Implement manually controlled Blocks production

Generate nonce, include transactions from pool, publish block

Implement network time

Add dependency management (vgo)

Task1: blockchain wirefrime

Define node building blocks

currency: manage sums

• Validate transactions values - check if sender has required funds
• Implement block production reward

Count code coverage, increase if needed

Implement longest chain switch

distribution: pack into docker

Balances and Poll are in incorrect state after switching to a longest chain

Task:3 basic transactions cryptography

Implement signing/verification

p2p: add peers advertising

Task:4 transactions publishing

Node generated transaction has to publish transactions to network, and peers should:

1. verify sign/hashes
2. verify sender has the money
3. add to unconfirmed pool

Gossip not working: published blockchain entity is not being retransmitted

Received through publishing blocks, transactions and votes have to retransmitted to other peers in case they are valid

Network instability can cause unhandled incoming blocks order changes

If child block has arrived before parent, node will stop chaining as both and all following blocks will be declined.

Race condition when adding transactions to pool

Consensus: prevent double voting, decrease delegate votes if vote was given to someone else

• implement some freeze period for voter

Task:2 p2p basic exchange

1. Establish communication with one peer
2. Retrieve sample blocks from peer
3. Add more peers