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QuantumPimp
join:2012-02-19

QuantumPimp to UK_Dave

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to UK_Dave

Re: Best way to minimise downtime moving back to Bell.

Must be referring to trunk back to CO. Digital Signal 3 (DS3) is 44.736 Mbit/s copper and OC-3 is 155.52 Mbps fiber.
HeadSpinning
MNSi Internet
join:2005-05-29
Windsor, ON

HeadSpinning

Member

said by QuantumPimp:

Must be referring to trunk back to CO. Digital Signal 3 (DS3) is 44.736 Mbit/s copper and OC-3 is 155.52 Mbps fiber.

More likely, the actual uplink card out of the DSLAM. Each DSLAM is made up of a complex of shelves. The main control shelf has an uplink card to tie the complex back to the aggregation switch. When Bell encounters congestion, they would swap the uplink card from DS3 to OC3. If they've already got an OC3 uplink, they split the complex into two, and give each group of shelves their own uplink.

Regardless, they're still dealing with Legacy ATM technology at that point, and the components aren't manufactured anymore. They're likely re-purposing old cards that have been taken out of service in areas they upgraded to 7330. It's a bit of a Band Aid approach. You're still dealing with at most a 155 Mbps connection - and with ATM encapsulation, the maximum throughput is roughly 130 Mbps of actual data.

We had a bunch of legacy ATM DSLAMS in our network (installed in 2001/2002), but were fortunate enough to buy a bunch of GigE uplink cards from the manufacturer before they discontinued the product line. We've got almost all our Legacy ATM gone from our network, replaced with GigE.