Lidgren.Network is a networking library for .net framework which uses a single udp socket to delivers a simple API for connecting a client to a server, reading and sending messages. The following delivery methods is implemented:

• Unreliable unordered. Messages may or may not arrive and the order is undetermined.
• Reliable unordered. Messages will arrive (sooner or later), but the order is undetermined.
• Unreliable ordered. Messages may or may not arrive and the order is fixed, ie. old messages will not arrive after new messages.
• Reliable ordered. Message will arrive (sooner or later) in the same order they were sent.

All delivery methods rejects duplicate messages and UnreliableOrdered and ReliableOrdered can be sent in different channels. Other features includes:

• Message coalescing/combining into fewer packets
• Bandwidth throttling
• Message fragmentation
• Local server discovery
• Clock synchronization
• Connection statistics
• Lag, loss and duplication simulation for testing
• Peer to peer class

This the new version of my old networking library located at http://code.google.com/p/lidgren-library-network/