This document explains the architecture of the library components. The low-level networking and threading infrastructure makes use of async Tokio runtime. In the future, the code will be made modular so to allow the use of different runtimes.
The architecture follows the diagram below. For usage examples please refer to the crate's documentation
The kadcast::peer is the entry point of the library and the only public API. It implements the Kadcast Network Peer.
The Message Handler represents the core component of the library. It handles the incoming messages and replies according to the specification.
The Maintainer performs the initial bootstrap as well as the k-table maintenance.
It keeps track of idle buckets and is in charge of triggering the routing nodes lookup.
It is responsible to instantiate the UDP server that receives the messages from the network. It's also in charge of outgoing communication (UDP client). It performs message serialization/deserialization and applies the FEC encoding/decoding where appropriate.
The RaptorQ Encoder splits a single broadcast message in multiple chunks according to the RaptorQ FEC algorithm.
The RaptorQ Encoder joins the encoded chunks in a single decoded broadcast message. It keeps a cache to avoid processing brodcasted identical messages multiple times.
Provides message passing between incoming UDP packets (deserialized by the WireNetwork) and Message Handler
Channel dedicated to any message which needs to be transmitted to the network.
Successfully received broadcast messages are dispatched to the Notifier through the Notification Channel. This is done in order to safely forward messages to the user's callback without any risk for the latter to block any other thread.