Network

The network component is specifically designed to facilitate the consensus and shared mempool protocols. Currently, it provides these consumers with two primary interfaces:

RPC, for Remote Procedure Calls; and

DirectSend, for fire-and-forget style message delivery to a single receiver.

The network component uses:

· Multiaddr scheme for peer addressing.

· TCP for reliable transport.

· Noise for authentication and full end-to-end encryption.

· Yamux for multiplexing substreams over a single connection.

· Push-style gossip for peer discovery.

Each new substream is assigned a protocol supported by both the sender and the receiver. Each RPC and DirectSend type corresponds to one such protocol.

Only eligible members are allowed to join the inter-validator network. Their identity and public key information is provided by the consensus component at initialization and on updates to system membership. A new validator also needs the network addresses of a few seed peers to help it bootstrap connectivity to the network. The seed peers first authenticate the joining validator as an eligible member and then share their network state with it.

Each member of the network maintains a full membership view and connects directly to any validator it needs to communicate with. A validator that cannot be connected to directly is assumed to fall in the quota of Byzantine faults tolerated by the system.

Validator health information, determined using periodic liveness probes, is not shared between validators; instead, each validator directly monitors its peers for liveness.

This approach should scale up to a few hundred validators before requiring partial membership views, sophisticated failure detectors, or network overlays.