On Thu, Dec 4, 2008 at 7:18 PM, Michael Thomas <mike@mtcc.com> wrote:
We haven't really had a major catastrophe where we've been totally dependent on IP yet, AFIAK. Maybe all of the qos, call gapping and the rest of the stuff the TDM networks do to deal with disasters will be left in the dustbin of Moore's Law, but maybe they won't. One thing is certain: we'll definitely find out one day, and it's not likely to be from a position of having taken the precautions, congratulating ourselves IMO.
The only disaster I experienced which affected telecoms was the July, 2005 terrorist attack on London. Although the infrastructure wasn't affected, there were significant load challenges for the GSM nets especially. It was widely assumed by the unclued that either one or two GSM operators failed under peak load; by the clued that the Access Overload Control process, analogous to the PSTN's Government Telephone Preference Scheme, had been initiated to deal with the peak load. In fact, it turned out much later that AOC had indeed been declared, but unnecessarily, and against the decision of the lead agency dealing with the emergency. The Metropolitan Police didn't request it, but the (smaller) City of London force did, although the network in question was coping - the entire outage was caused by mismanaging the TDM call-gapping and QoS features. Both the Internet, and our corporate VoIP system including its peering with the wider PSTN, worked throughout.