LiteNetLib

Lite reliable UDP library for .NET Framework 3.5, Mono, .NET Core 2.0, .NET Standard 2.0.

Little Game Example on Unity

Features

• Lightweight
  • Small CPU and RAM usage
  • Small packet size overhead ( 1 byte for unreliable, 3 bytes for reliable packets )
• Simple connection handling
• Peer to peer connections
• Helper classes for sending and reading messages
• Multiple data channels
• Different send mechanics
  • Reliable with order
  • Reliable without order
  • Reliable sequenced (realiable only last packet)
  • Ordered but unreliable with duplication prevention
  • Simple UDP packets without order and reliability
• Fast packet serializer (Usage manual)
• Automatic small packets merging
• Automatic fragmentation of reliable packets
• Automatic MTU detection
• UDP NAT hole punching
• NTP time requests
• Packet loss and latency simulation
• IPv6 support (dual mode)
• Connection statisitcs (need DEBUG or STATS_ENABLED flag)
• Multicasting (for discovering hosts in local network)
• Unity support
• Supported platforms:
  • Windows/Mac/Linux (.NET Framework, Mono, .NET Core)
  • Android (Unity)
  • iOS (Unity)
  • UWP Windows 10 including phones
  • Lumin OS (Magic Leap)

Unity notes!!!

• Always use library sources instead of precompiled DLL files ( because there are platform specific #ifdefs and workarounds for unity bugs )

Usage samples

Client

EventBasedNetListener listener = new EventBasedNetListener();
NetManager client = new NetManager(listener);
client.Start();
client.Connect("localhost" /* host ip or name */, 9050 /* port */, "SomeConnectionKey" /* text key or NetDataWriter */);
listener.NetworkReceiveEvent += (fromPeer, dataReader, deliveryMethod) =>
{
    Console.WriteLine("We got: {0}", dataReader.GetString(100 /* max length of string */));
    dataReader.Recycle();
};

while (!Console.KeyAvailable)
{
    client.PollEvents();
    Thread.Sleep(15);
}

client.Stop();

Server

EventBasedNetListener listener = new EventBasedNetListener();
NetManager server = new NetManager(listener);
server.Start(9050 /* port */);

listener.ConnectionRequestEvent += request =>
{
    if(server.PeersCount < 10 /* max connections */)
        request.AcceptIfKey("SomeConnectionKey");
    else
        request.Reject();
};

listener.PeerConnectedEvent += peer =>
{
    Console.WriteLine("We got connection: {0}", peer.EndPoint); // Show peer ip
    NetDataWriter writer = new NetDataWriter();                 // Create writer class
    writer.Put("Hello client!");                                // Put some string
    peer.Send(writer, DeliveryMethod.ReliableOrdered);             // Send with reliability
};

while (!Console.KeyAvailable)
{
    server.PollEvents();
    Thread.Sleep(15);
}
server.Stop();

NetManager settings description

• UnconnectedMessagesEnabled
  • enable messages receiving without connection. (with SendUnconnectedMessage method)
  • default value: false
• NatPunchEnabled
  • enable NAT punch messages
  • default value: false
• UpdateTime
  • library logic update (and send) period in milliseconds
  • default value: 15 msec.
• PingInterval
  • Interval for latency detection and checking connection
  • default value: 1000 msec.
• DisconnectTimeout
  • if client or server doesn't receive any packet from remote peer during this time then connection will be closed
  • (including library internal keepalive packets)
  • default value: 5000 msec.
• SimulatePacketLoss
  • simulate packet loss by dropping random amout of packets. (Works only in DEBUG mode)
  • default value: false
• SimulateLatency
  • simulate latency by holding packets for random time. (Works only in DEBUG mode)
  • default value: false
• SimulationPacketLossChance
  • chance of packet loss when simulation enabled. value in percents.
  • default value: 10 (%)
• SimulationMinLatency
  • minimum simulated latency
  • default value: 30 msec
• SimulationMaxLatency
  • maximum simulated latency
  • default value: 100 msec
• BroadcastEnabled
  • Allows receive Broadcast packets
  • default value: false
• ReconnectDelay
  • delay betwen connection attempts
  • default value: 500 msec
• MaxConnectAttempts
  • maximum connection attempts before client stops and call disconnect event.
  • default value: 10
• UnsyncedEvents
  • Experimental feature. Events automatically will be called without PollEvents method from another thread
  • default value: false