microsoft-signalr

ASP.NET Core SignalR is an open-source library that simplifies adding real-time web functionality to apps. Real-time web functionality enables server-side code to push content to clients instantly. This client can also be used with the Azure SignalR Service for enabling serverless real-time experiences.

signalrwebsocket

https://github.com/aspnet/AspNetCore/tree/master/src/SignalR#readme