[c-nsp] Aggregating IP DSLAMs to a single site

[Kim Onnel]

Hello,

If we have a bunch of IP DSLAMs with Ethernet uplinks on different sites and
we want to aggregate them to a single Ethernet switch in the main exchange
near to our internet gateway, what are the known cost-effective methods?
(knowing that the Teleco company here does not provide Metro ethernet
connectivity, so i have to convert from ethernet to something else and back
again at the collection point)

Take into consideration that the IP DSLAMs sometimes provide 3-4 E1s worth
of traffic, i.e: not because its an ethernet uplink it means we have alot of
uplink traffic.

I'm not a transmission guy, but i heard the following:

1) on the edge sites, convert the ethernet to E1s using CPEs and then
collect back the E1s on a big router with alot of E1s links.(doesnt sound
cost-effective at all)

2) CPEs on the edges and then one MSTP device (like Cisco ONS) to collect
the E1s and give one Ethernet uplink

3) CPEs on the edges and then the teleco shall aggregate all the E1s to one
MUX and give one cPoS interface on a router.

4) MSTP devices on both sides

Please help, vendors are trying to rip me and i need to know which method is
efficient and cost-effective, are these all the factors or am i missing
something ?

Thanks in advance, private messages are welcomed.

Kim