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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: T3 to E3 conversions
| 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. In places like 60 Hudson St or 111 8th Av, or anywhere at all in Europe that Colt or MFS (as examples) go, you should push for a full VC3 rather than just a T3 or E3, assuming you have a way of using it. Elsewhere you will more likely be stuck with T3 or E3. | No, I don't know why at the E1/T1 level E1 is the preferred way of doing it. It's historical. Terminating E1s in D.C. (or anywhere else in the US beyond the switches talking to the cables) was a mess involving special gear. Terminating T1s in Europe "couldn't be done". These days, since there are the VT1.5 and VT2 in SONET land and the TU-11 and TU-12 in SDH land, the "standards gap" is fixed by digital cross-connection; the choice of T1 vs E1 payload is mostly down to who has the right trib cards, and who has the most PDH cruft in the way, or (cynically) down to E1s likely bringing in more revenue. Sean.
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