NexRes is the next generation of ResilientDB, an open-source high-performance Remote Procedure Call (RPC) framework running in a byzantine environment. It provides a simpler system structure and kind APIs so that developers can be able to explore their research or implement their applications in a more convenient way.

NexRes is still Written entirely in C++, which offers compatible interfaces to most any other programming languages. NexRes introduces Bazel which is a compiling tool that helps us to manage the compiling environment. Bazel provides a strong capability to make the compiling easier and the library dependency clear, comparing to Makefile.

NexRes also adopts Protobuf Buffer to serialize and deserialize structured data.

System Architecture

NexRes contains three layers: Application, Consensus, and Network. Developers can explore any layer they are interested in without accessing others.

Application

The application addresses the transactions published by the users. NexRes guarantees that once the application receives a transaction, this transaction has been committed by some consensus protocol handled by the Consensus layer. Developers do not need to consider how the transactions are committed.

Consensus

Consensus tackles the consensus algorithm to commit the transactions. Normally, it contains two phases: ordering and execution. Ordering helps to order each transaction in the system by running some consensus protocol, like PBFT. Once the transactions are committed with a sequence id, they will be executed in sequence in the execution phase by calling the Application.

Network

The network handles message delivery. It helps the system to receive messages from other machines and deliver messages to them. NexRes uses a coroutine to improve the system’s performance. Moreover, each machine will keep connecting with each others in a cluster to reduce the connection cost.