At 12:52 PM 9/14/97 -0400, Alan Hannan wrote: [whack...]
pps. I'm really not all that in love with ATM. But it does work. If IP could do the things that ATM/FR can, then off we go. My experience and knowledge say that managing a really large, dynamic, and robust network requires more than flexibility than L1 pipes and L3 routers. Something in the middle is needed to smooth out the corners.
It runs at right angles to my nature and my intellect, but in the networking world I've become a huge fan of pragmatism (if it works right now, do it). Building out a national network on a bizarrely short timeline, with no idea of what traffic flows would look like, I found ATM a great way to get things started. If my initial estimates were wrong (and they were), just provision more bandwidth between the two distressed endpoints. And frequently that bandwidth was available in days/weeks as opposed to the months that it was taking to get DS3s to build out a ring. So now I think in terms of the appropriate technology for the job; packet over SONET is a terrific way to connect two L3 devices which currently exchange ~40 Mbps and will probably want to exchange ~150 Mbps (or ~600 Mbps, or ...) within a few months or a year. But when you're trying to bring up a new device in a bandwidth starved city (Seattle a year ago comes to mind) and DS3 ATM is the only thing you can get, ATM does a bang up job, even if it's only 1 PVC to somewhere else. The network equipment market has made an outstanding leap from one choice (some would argue no choice) of tools to do any given job, to multiple tools to do the same job in any number of slightly different ways. Each tool, and each approach, is appropriate to some real-life situation. So given the pants-on-fire growth in this business, and the disjoint ways demand for equipment and bandwidth move v. supply, I'm in love with whatever works right now. -peter