[c-nsp] SP-grade Ethernet over TDM

[Justin Shore]

Does anyone have any suggestions for providing Ethernet links over 
bonded T1s?

We originally looked at Overture.  They claimed that their product used 
standard MLPPP and interoped well with 7200s.  They sent out a tech to 
help configure it in a lab.  As it turns out they also require the use 
of BCP (Bridging Control Protocol).  To use BCP on a 7200 step #1 is to 
disable IP routing (literally, 'no ip routing').  That is required to 
facilitate bridging VLANs over MLPPP bundles.  Needless to say this 
wasn't an option since our router was doing more than just terminating 
EoTDM connections.  If we had an old 7200 sitting around we probably 
could have pulled it off.  Alternately, if we have a 7600 in that colo 
with DS3 SPAs we could have done the same thing without disabling 
routing.  I'm considering replacing that 7200 with an ASR in the future 
so perhaps this will become possible once again down the road, but not 
today.

I've also been looking at Adtran's Ethernet over TDM products.  It looks 
like you have to use their Total Access 5000 at the hub and then use 
their NetVanta 800 series as the CPE.  I don't know anything about the 
Total Access 5000 and can't access their documentation without an 
account (hard to sell the product when you won't let people access the 
docs beforehand).

Overture's CPEs for this application are the 140 and 180 models.  The 
price is right but the product just doesn't have a production SP-grade 
feel to it.  Management has to be done locally.  There isn't a CLI 
option which I would think would be a requirement for SPs wanting to 
either script changes or backup configurations.  It just doesn't feel 
production grade or SP-grade by any means.  It's not like their 2200 or 
5000 products which are much better.  I've always heard good things 
about Adtran and that they are Cisco-like but I've never actually used them.

What I'd like to find is a device that can bond multiple DS1s together 
with standards-based MLPPP and then bridge that to an Ethernet interface 
behind it.  I imagine that this would interop with our 7200s nicely.  It 
would be nice if there was some mechanism for in-line management as 
well, though I'm not sure how that would work short of pulling out a DS0 
for management access.  Does anyone know of such a product?  Does anyone 
know of any other ways of accomplishing that same or similar thing?  I 
don't know of any cisco products that can do this.  I could foresee a 
situation where I need multiple VLANs at the customer premise so the 
Adtran solution would likely fit in better with this potential need.

Thanks
  Justin