.NET 5 introduces networking features which includes improvements around HTTP, Sockets, networking-related security, and other primitives, such as
- The ability to distinguish timeouts from cancellations
- Consistent Cross-Platform Implementation
- SocketsHttpHandler Extension Points
- Sync API for HttpClient.Send
- Multiple Connections with HTTP/2
- HTTP/2 Configurable Ping
- Preview of HTTP/3 and QUIC protocol
- Better Cancellation Support
… and lots more
Source: .NET 5 Networking Improvements | .NET Blog
Lars Fosdal 