A communication port provides interprocess communication between IBM® Rational® Rhapsody® and instrumented applications. Unlike a regular message queue, which is used for communication between tasks on the same processor, a connection port has some unique identification, generally a socket address and number, that allows Rational Rhapsody to communicate with processes running on either the same machine or different machines. This structure allows the product to communicate, for example, with an animated application running on a remote target board.
Rational Rhapsody requires the TCP/IP protocol to be installed on the host machine. Processes connect to the animation server through the connection port using the TCP/IP protocol. The port number is included at the start of message packets that are addressed to the animation server.
The following figure illustrates the interprocess communication.

Note the following information:
The instrumented application can be running on either the same machine as Rational Rhapsody (the host machine) or on a remote target.