Has anyone figured out a way to instantaneously swing over PRIs bearing calls in progress to another media gateway without dropping them? Obviously, this would require a DACS of some sort. But I am thinking that it is possible to swing T1s over in a DACS without actually causing the endpoint to reframe as long as the other endpoint is kept in sync. So, it'd be nice, for example, to bring in some PRIs through a small DS1-level DACS, and be able to swing them over among various boxes with quad-span Sangoma or Digium T1 cards in the event of a problem without dropping any calls. I do not imagine there is a way to do this easily from an engineering point of view; it would require constantly synchronised PRI interfaces on the hardware and intermediate (zaptel) level, and essentially massively parallel Asterisk and loads of RPC. But I imagine there is good ROI in developing something like this. Even developing a way to transparently switch SIP calls in progress (together with the media and dialog state) to another Asterisk installation seamlessly would be good, if nobody wants to go through all the other of making this work on the TDM level. Any allowance for that type of failover clustering? -- Alex Balashov Evariste Systems Web : http://www.evaristesys.com/ Tel : +1-678-954-0670 Direct : +1-678-954-0671