Michael Richardson writes: > > I was downtown Ottawa on the Friday, eating at a restaurant that had power, > since we had none at home. (at least, when we arrived they had power...) > > What I noticed is that my GSM (Fido/Microcell) had very poor reception, > and I frequently didn't get a signal. My conclusion - they don't have all > of the transponders on generator backup, so they have less capacity during > a blackout. > > Repeating this design for IP telephone would not be a good idea :-) Actually, we're about to repeat it in a much worse way. John pointed out that IP routed around problems during these outages, but I don't think that we should too glib about how real life those tests really were wrt VoIP: voip traffic is still a tiny fraction of TDM where it counts (ie, at congestion points and especially at the slow edges). I despair that it will not be till way too late that we discover -- unsurprisingly -- that flash crowds and IP brownouts are not only possible, but to be expected. More's the pity that we have both the standards and the deployed code (RSVP) to largely avoid this disaster in the making. I think that there's some belief that this is a technical problem with RSVP (too heavy, too whatever), but I think that's a gloss: signaled QoS is just plain hard and heavy and slow and all kinds of other unpleasant things by its very nature. No technical solution is going to make it into diffserv or best effort. So we're going to have a disaster and then Congress will do what the industry couldn't... Mike