Communication Agent Overview

Communication Agent (ComAgent) includes infrastructure features and services for enabling inter-server communication. ComAgent provides the connection management, reliable routing services and software compatibility management, and supports mechanisms for exchange of Stack Events between stacks hosted on different Message Processors (MPs). ComAgent successfully routes messages between layers across processes and servers.

The ComAgent's Routed Service provides a means by which local applications hosted on an MP can send traffic to applications on other MPs. The ComAgent's Routed Service has Connection Groups associated with the service assigned with different priorities. When an application sends events to other servers using a routed service, the ComAgent chooses a connection in the highest priority group for that routed service and sends the event on that connection. The load-balancing accounts for:

• Connection Group status (an aggregation of member connection status)
• Connection availability status (same as server availability status)
• Connection Egress Congestion Level (CL)
  • Transport Connection Congestion Level (TCL)
  • MP Overload Level (OL) of peer server
• Ingress Message Rate
• Provider State (State of the service published by the Service Provider)

Note:

ComAgent supports one Connection Group per Routed Service.

The ComAgent menu also provides you with a means to monitor the operational status of High-Availability (HA) Services Sub-Resources. The HA Services enables a server application to load-share its active functions across a set of servers and to notify clients of the placement of its active functions onto servers in a manner that allows the clients to send stack events to the active functions. The set of active functions is called a Resource and each active function instance is called a Sub-Resource.