[c-nsp] Carrier access on existing channelized DS3?

[Josh Higham]

We have a channelized DS3 from the ILEC, and when getting price quotes I
specify that I will provide the loop for the service.

I spoke with MCI/UUnet today, and their sales rep bought in a pre-sales
engineer to strongly urge against that configuration.  Some of the
reasons I can deal with (they don't provide SLA, toubleshooting can
involve finger pointing), but they also had some technical issues that
didn't sound right to me.

The engineer said that if they provision they can choose ports on the
DAX(?) to have the best timing match.  If they ride the DS3 they don't
have that choice, so they get timing errors.  Is there any validity to
this?  As far as I know (not very far :-) timing is per T1 line, and
there is no relation between timing on different circuits.

Thanks,
Josh