B_Verify

Warning: this is pre-release software. Use on testnet only.

B_Verify is a protocol to practically and scalably prove non-equivocation using Bitcoin. B_Verify witnesses logs of statements to Bitcoin, and, under the assumption that no one can double spend transaction outputs, B_Verify guarantees that all clients will see the same sequence of statements. B_Verify can scale to prevent equivocation for millions of applications: B_Verify can witness thousands of new log statements per second at a cost of fractions of a cent per statement. B_Verify accomplishes this by using an untrusted server incentivized by a smart contract to witness many new log statements with a single Bitcoin transaction. Users in B_Verify maintain small proofs of non-equivocation which require them to download only kilobytes of data per day. We implemented this prototype of B_Verify in Go.

Dependencies

In order to run the B_Verify server you will need to run a Bitcoin (testnet) node accessible over RPC

Build

You can grab the binary releases from this Github, or build the binaries yourself. In order to build them yourself, do the following:

go get github.com/mit-dci/go-bverify/...
cd $GOROOT/src/github.com/mit-dci/go-bverify/cmd/server
go build

Running

You can run the server by executing the server executable. Make sure the following environment variables are properly configured:

Variable	Description	Default
BITCOINRPC	The server and port on which the Bitcoin RPC server is listening	localhost:18443
BITCOINRPCUSER	The username for the Bitcoin RPC server	bverify
BITCOINRPCPASSWORD	The password for the Bitcoin RPC server	bverify

Code structure

The code in this project is structed as follows:

Folder	Description
bitcoin	Various imported libraries for Bitcoin
client	B_Verify client libraries
client/uspv	Simple Payment Verification library that is used to download headers from Bitcoin
cmd/bench	Command-line utility for running the benchmarks included in the B_Verify paper
cmd/server	Entry point for running the B_Verify server
crypto	Cryptographic functions and imports for witnessing and signature verification
logging	Very simple logging framework
mobile	The entrypoint for the gomobile library used in the Android and iOS Client
mpt	Implementation of the Merkle Prefix Trie
server	Classes containing the B_Verify server logic
smart-contracts	(Proof-of-concept) implementation of the Penalty Smart Contract
utils	Various utility functions
wallet	Class for tracking UTXOs for the server (used to create witness transactions)
wire	Classes for client/server communication

Related repositories

BVerify-Mobile

This repository contains the iOS and Android applications that are used for verifying the witnessed statements

BVerify-Sensor

This repository contains an integrated example for a sensor reader that commits to a b_verify server