NetOnewayRelayBinding supports one-way messages from client to the server. The method signatures for one-way methods in the service contract must not return any values. One-way methods are optimized for one-way TCP communications between the senders to the relay service and then to the receivers. The default size of the message is set to 65,536 bytes. The receiver using the NetOnewayRelayBinding opens a bidirectional TCP connection on outbound TCP port 828 for an SSL connection and TCP port 808 for a non-SSL connection. If the TCP outbound ports are unavailable due to environmental policies or port conflicts, you can configure the AppFabric Service Bus to use the HTTP protocol instead. The HTTP protocol polls the relay service through outbound ports 443 for SSL and 80 for non-SSL communications.
NetEventRelayBinding extends the netOnewayRelayBinding by providing multicast messaging between multiple subscribers and publishers listening on the same rendezvous service endpoint. The netEventRelayBinding class inherits from netOnewayRelayBinding. This is the only binding that supports multiple receivers on the same service URI.
netTcpRelayBinding is the recommended and most frequently used AppFabric Service Bus binding. It uses TCP as the relay transport and is based on the WCF netTcpBinding. It performs better than the HTTP bindings, because it uses TCP for message delivery and the messages are encoded in binary format. NetTcpRelayBinding supports WS-ReliableMessaging, which is turned off by default. You can turn it on by setting reliableSessionEnabled to true. In WCF, you typically use netTcpBinding to create service endpoints reachable within the intranet, but with netTcpRelayBinding you can create service endpoints reachable over the Internet. This makes communication over the Internet faster than with HTTP bindings. Similar to netOnewayRelayBinding, netTcpRelayBinding establishes an SSL-protected control channel using outbound TCP port 828 and a non-SSL data channel using outbound TCP port 818.
AppFabric Service Bus supports the following HTTP relay bindings: