kcp2k

C# KCP based on the original C kcp.

Works with netcore and Unity.

Developed for Mirror Networking.

Questions & support on Mirror Networking Discord.

Features

Kcp.cs based on kcp.c v1.7, line-by-line translation to C#
Heavy test coverage
Fixed WND_RCV bug from original kcp
Optional high level C# code for client/server connection handling
Optional high level Unreliable channel added

Pull requests for bug fixes & tests welcome.

Unity

kcp2k works perfectly with Unity, see the Mirror repository's KcpTransport.

Allocations

The client is allocation free. The server's SendTo/ReceiveFrom still allocate.

Previously, where-allocation for a 25x reduction in server allocations. However:

It only worked with Unity's old Mono version.
It didn't work in Unity's IL2CPP builds, which are still faster than Mono + NonAlloc
It didn't work in regular C# projects.
Overall, the extra complexity is not worth it. Use IL2CPP instead.
Microsoft is considering to remove the allocation.

Remarks

Congestion Control should be left disabled. It seems to be broken in KCP.