Adapters

Communication interface components

An Adapter is a software component that is a configurable part of a Message Server. There are different types of Adapters. As illustrated below, each type communicates with a unique type of external interface such as TCP sockets, IBM MQSeries® queues, or Microsoft® MSMQ queues. A typical Adapter is capable of both receiving messages from an external communications interface and sending messages to the same type of external communications interface.

imgAdapter-NetBIOSToTCP

Each Message Server can have up to two Adapters: an A-Side Adapter and a B-Side Adapter.  The Adapters operate independently and may be of different types or of the same type. In the Message Server illustrated below, the protocol employed to transport the message is being converted from TCP to an IBM MQSeries® connection. A message may be received by the TCP Adapter and forwarded to a queue using the MQSeries® Adapter. The associated response may be received by the MQSeries® Adapter and forwarded by the TCP Adapter.

imgAdapter-TCPToMQ

A Loopback can also be used for the B-Side Adapter. As illustrated below, the A-Side Adapter interfaces with TCP ports; the A-Side Filter provides some messaging transformation; and the B-Side Filter provides the interface to a .Net Assembly.

imgAdapter-TCPToDotNET

Similarly, it is possible that the B-Side Filter provide the interface to Java bytecode as illustrated below.

imgAdapter-TCPToJava

Supported Adapters

The following Adapters are supported in the Plexus Message Broker:

IBM WebSphere MQ Provides connection to IBM MQSeries® queues. Queues may be either local or remote queues.
Microsoft MSMQ Provides connection to Microsoft® MSMQ queues. Queues may be local or remote private queues.
TCP/IP Provides connection to TCP sockets. Message framing of the TCP data stream is specified in the configuration file.
NetBIOS Provides connection to NetBIOS sessions
SNA Provides connection to LU 6.2 sessions
LoopBack A stub adapter used as a placeholder but provides no functionality. Typically, in these cases, the Filter is either the application or an interface to an application.

Note: Some communication interfaces have built-in message framing technology such as IBM’s MQSeries®, Microsoft’s MSMQ, NetBIOS, or LU 6.2.  TCP does not contain such a technology.  Thus the TCP Adapter provides support for a number of message framing protocols so that the TCP adapter can identify a complete message.