Which Avaya component acts as a policy server?

The Avaya Aura Session Manager serves as the policy server within the Avaya architecture. It is responsible for routing calls, managing session control, and enforcing policies for ensuring quality of service and security during communications. The Session Manager enables the integration of different communication systems by handling SIP signaling and directing calls based on defined policies, which can include routing based on the availability of resources or user preferences.

By supporting various communication endpoints and enabling interoperability between different Avaya components, the Session Manager plays a crucial role in maintaining an organized and efficient communication environment. It ensures that policies on call handling, session management, and service access are consistently applied, aiding in both call control and resource management. This centralized policy enforcement is essential for an organization's communication strategy, ensuring that users have seamless access to the resources they need while maintaining control over how calls and sessions are managed.

The other components listed in the question serve different roles in the Avaya ecosystem. For instance, Avaya Aura Messaging provides voice messaging capabilities, Avaya Aura System Manager handles the management and administration of the various components, and Avaya Communication Manager is focused on the core telephony and call processing functions. Each component complements the Session Manager, but it is the Session Manager specifically that acts as the policy server.