I don't quite see what all the fuss is about. Clustering SIP proxies is pretty straightforward.
The rules for SIP proxies are designed to be only transaction-stateful, not dialog-stateful, and the proxy can fall back to being stateless if it has to be. So -- When a proxy is transmitting a request, it puts into the Via a domain name which resolves preferentially to itself (to provide transaction- stateful service for the response), and secondarily to its cluster-mates (to provide stateless service for the response if it fails). Any Record-Routes are domain names that (1) (if the Record-Routed proxy does not need to be dialog-stateful) resolves to a redundant group of proxies, or (2) (if the Record-Routed proxy wants to be dialog-stateful) resolves primarily to one proxy and secondarily to that proxy's cluster- mates. (Of course, if the fallback has to be used in case 2, there has to be some strategy for the clustered group of proxies to reassemble or duplicate their dialog state information. But in a high-availability situation, that needs to be done anyway.) Dale --- interop.pingtel.com -- the public SIP phone interoperability test server _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
