T3 to E3 conversions

Alex Bligh amb at gxn.net
Tue Jul 14 09:32:37 UTC 1998


> How do carriers handle E3 to T3 conversions?  What equipment is used?  I
> have heard that trans-Atlantic carriers sell E3s to Europeans when in fact
> it is a T3 with T3 costs passed on the customer and merely convert the line
> from T3 to E3 - thereby causing 11Mb/sec of b/w to be wasted.  Any truth to
> that?

The model over here for the newer carriers seems to be:
* Buy in 45Mb chunks or larger
* Either mux to E1s (2Mb/s) or run layer 2 (ATM over it) or sell whole
* Sell large circuits to the US as T3s not E3s

We buy our transatlantic stuff with T3 ports either end, all our domestic
private circuits as T3s, and everything else internationally is carried
on circuits which use SDH and the "T" hierarchy. May be I'm unusual in
this respect, but I know people who have bought from BT and got T3s too.

No, I don't know why at the E1/T1 level E1 is the preferred way of doing it.

Alex Bligh
GX Networks (formerly Xara Networks)

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