Advanced Warning: Qwest/Lucent ATM upgrade

Routing may be weirder than normal this evening. Qwest is upgrading
their Lucent ATM switches to fix a bug, and needs to shutdown their
entire ATM backbone for a couple of hours. Qwest hasn't responded to
my e-mails asking what is happening, but other ISPs have outlined
alternative routes they will be using. Most will try to maintain
service by additional peering, deaggregated routes, or temporary
third-party transit.

Other providers use Lucent ATM switches. I don't know if they
will also need to upgrade their networks at some time in the future
to fix the same problem.

RE: what is happening.

2 possibilities that we've already had to deal with, since they're on a GX
switch platform: PNNI doesn't work between the GX and the Lucent PSAX on
any but (I believe) the most current rev of GX *and* PSAX software, and
there's a bug on the GX platform which causes "directed PVCs" to stop
passing traffic until manually reset. A final option is that we've had a
couple of processor boards in the GX fail and, instead of passing control
over to the redundant board, the switch goes off-line and has to be
manually reset. I'm unsure if this is a hardware or software bug.

RE: upgrades.

It is pretty safe to assume that most GX customers are going to need to do
an upgrade in the near future. We just finished one, but were able to do
it incrementally. It was the third we've had to do in 6 mos. to iron
out GX-PSAX and management problems. I'm not sure what would
prompt Qwest to upgrade the whole network at once, though.



p.s. -- go easy on me ... i'm not the ATM guru. I'm just reporting what
has come up during engineering discussions with Lucent.