Overview
The primary purpose of Genesys SIP Proxy is to provide high availability without requiring a virtual IP address.
There are five fundamental concepts to understand:
1. The purpose of SIP Proxy is to provide high availability for a primary/backup SIP Server HA pair without requiring a "virtual" or floating IP address.
2. An N+1 pool of proxy instances is defined for each SIP Server HA pair. The proxy instances monitor the SIP Server pair to determine which is active and which is backup.
3. Incoming SIP messages are proxied to the primary SIP Server instance. It is the responsibility of external SIP user agents to select a proxy instance based either on DNS or static configuration of multiple IP addresses, and to fall back to an alternate instance if the selected instance is not responding.
4. The SIP Server HA pair is configured to use this pool of SIP Proxy instances as the "outbound proxy."
5. SIP Proxy functions as a proxy defined in RFC 3261 section 16.
As of March 2013, SIP Proxy has been tested with only two SIP endpoints - the Genesys SIP Endpoint v8.1, and Polycom SoundPoint IP Phones; additional endpoints are scheduled for testing.
Standalone deployment
In a standard deployment, an N+1 pool of SIP Proxy instances handles incoming & outgoing SIP transactions between a SIP Server HA pair and external SIP elements. Each SIP transaction would be handled by a single proxy instance. Subsequent transactions may be handled by the same or different proxy instance(s). Each SIP Server HA pair requires a unique pool of proxy instances.
