Tuesday, 5 July 2011

SIP call recovery in gateways

Life is full of truisms; those self-evident truths in statements like not being able to recover your lost youth (despite what plastic surgeons say – or any number of elderly film stars have wished). It’s not as evident that you can’t recover SIP (session initiation protocol) calls when they appear to fail. What happens when you lose an already established SIP call between a gateway and an end point on a VoIP (voice over Internet protocol) network? Can it be recovered? It depends on what you mean by ‘lose’ and ‘recover’.

Dictionary definitions of recovery suggest many things, from salvage to sports. The latter always gives good value for analogies, don’t you think? How about a recovery stroke in golf; playing from the rough to the fairway (or a bunker to the green) – hands up if you’re familiar with that one.

Recovery also covers recuperation (as in convalescence) in addition to repossession and retrieval. In disaster planning – getting closer to technology and SIP call recovery – recovery means the steps to be taken to return all operations and systems to their normal status. In electronic commerce – getting closer still – it’s the ability of a system to be restored so that processing can resume and transactions, aborted due to a failure, can be resubmitted.