PPPoE vs. Bridged ADSL

Wed Oct 28 21:20:36 UTC 2009

There is a debate among our engineering staff as to the best means of 
provisioning broadband service over copper facilities. Due to our 
history, we have a mix out in the field. Some customers are on DSLAMS 
set up for bridged connections with DHCP; isolated by a variety of means 
including VLANS. Some customers are on PPPoE over ATM. Some customers 
are on PPPoE over ethernet (PPPoEoE ?? :) ).

There seem to be pros and cons to both directions. Certainly true 
bridging has less overhead. But modern CPEs can minimize the impact of 
PPPoE. PPPoE allows for more flexible provisioning; including via 
RADIUS. Useful for the call center turning customers on/off without NOC 
help. But VLAN tricks can sometimes do many of the same things.

Opinions on this? I'd be interested in hearing the latest real world 
experience for both and the direction most folks are going in.

BTW, I doubt it is relevant to the discussion, but most of our DSLAMS 
are Adtran TA5000s (or are being migrated to that platform.) We are 
mostly a cisco shop for the upstream routers.

Thanks,

John