Compare the broker/agent architectures of the Classic OpenEdge AppServer and the Progress Application Server for OpenEdge that is illustrated in the following diagram:
Figure 4. Agents in Classic OpenEdge AppServer compared to PAS for OpenEdge
The architecture of the Classic OpenEdge AppServer uses a Broker to assign requests to Agents that execute as independent ABL sessions in multiple OS processes.
As the diagram shows, PAS for OpenEdge replaces the Broker with a Session Manager. The Session Manager manages a pool of ABL sessions running in the context a single Multi-session Agent (MSAgent) which is a single OS process. Note that the Session Manager can generate and manage more than one Multi-session Agent.
