I am trying to understand what type of packets move between a DSLAM and BRAS.
I have read the sticky "DSLAM basics" which gives great insight, but still leaves some questions unanswered for me.
ATM DSLAMs send ATM cells between DSLAM and BRAS (no surprises here)
Ethernet DLSAMs send ethernet Frames between DLSLAM and BRAS which means all IP and PPP traffic go over ethernet (no surprises here)
IP DSLAMs - this is where I am still a little confused so this is where my quesions start.
1. What I'm trying to figure out is, are IPDSLAM pure IP therefore backhaul between DSLAM and BRAS can be sent over a pure IP solution that does not support Layer 2 traffic.
2. On a IPDSLAM does only IP traffic pass b/w DSLAM and BRAS or are there also layer 2 services being provided
3. For IPDSLAM what happens to PPPoE traffic, does the DSLAM act as a proxy and forward the PPPoE traffic via IP to BRAS.