Michael Dillon <michael@memra.com> wrote:
Are you sure that creative ways of using lots of smaller T3 bandwidth boxes couldn't solve the problem?
There are hard architectural limits on the number of core routers in the defaultless backbone. Backbone has to have a relatively small number of BGP speakers, to avoid severe routing information propagation problems. There _are_ "creative ways", see for example SprintLink presentations on NANOG, the planned "3-dimensional grid" backbone topology (it allows to grow the aggregate capacity to about OC-3). However, you inevitably run into capacity limitation of LAN interconnects. Then, there's a problem with load balancing, as it generally cannot be done with exterior protocols which have to select a single path. (And there's no easy way to do per-destination load distribution on a large scale). It's only a kludge to survive until (and if) somebody will build real central-office routers.
If you are right, then yes it sucks. Obvoiusly the ATM and OC3 technologies are right where you have pegged them, but what about parallelism using existing DS3 technology? And if this is done, are there mux/demux boxes that can handle DS3's<->OC3 ?
There are boxes which can *statically* mux/demux OC-192 to DS-3s. Synchronous muxes is not a high technology, being basicallly decorated shift registers.
One nice side effect is that this may force the video-on-demand folks off the Internet and into straight ATM instead. I rather like the future scenario where the globe is girdled by an IPng data network and a separate parallel video/ATM network.
That already happened. I would rather see things going in opposite deirection. (For VOD applications ATM is adequate, as it only demultiplexes big pipes from VOD servers into small access pipes; there's no backwards data flow, and no statistical multiplexing). However, the utility of VOD is very questionable, as the basic need to see the movie quite adequately and cheaply satisfyed by low-tech video rentals. It is not a "killer application", definitely. Video telephony and distributed computing network can be such applications but they beg for symmetrical IP connectivity. --vadim