Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!magnus.acs.ohio-state.edu!zaphod.mps.ohio-state.edu!wuarchive!uwm.edu!bionet!agate!telecom-request From: john@zygot.ati.com (John Higdon) Newsgroups: comp.dcom.telecom Subject: Re: Questions About New Service Being Installed Message-ID: Date: 24 Mar 91 03:34:00 GMT Sender: Telecom@eecs.nwu.edu Reply-To: John Higdon Organization: Green Hills and Cows Lines: 36 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 234, Message 7 of 10 "Dennis G. Rears (FSAC)" writes: > I found out my new service will be serviced by a 1ESS switch. Can > anybody explain the difference between that and a 5ESS switch? I > would really appreciate it if somebody could detail what each switch > capability is. The 1ESS is the original Electronic Switching System. It is archaic. It is essentially an electronically controlled mechanical switch. The processor is slow and the memory is small and as a result its feature offering is deficient. It does not have enough feature store for SS7 and hence cannot provide CLASS features. Its Call Waiting cannot be temporarily cancelled (not enough room for CCW in the feature store). The 1AESS is the mid-seventies enhancement of the 1E. It uses a much more capable processor, a greatly expanded (and faster) memory, and a rich feature offering, although it is still analog. It can offer all features, including CLASS and its feature implementation is considered industry standard. To the ear, it sounds identical to the old 1E and cannot be differentiated in that manner. (A good test is whether or not Cancel Call Waiting is available.) The 5ESS is AT&T's current flagship switch. It is fully digital and offers or will eventually offer every single CO switch feature known to mankind. It does ISDN, CLASS, everything. It has lousy three-way calling compared to either the 1ESS or the 1AESS, but you cannot have everything. It's three-way is better than a DMS100 without the proper hardware/software packages, however. I am told that someday (no one knows when) all the crossbar in my CO will all be replaced with a 5ESS. Couldn't help but be an improvement. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@zygot.ati.com | San Jose, CA 95150 | M o o !