Path: utzoo!telecom-request Date: Sat, 6 Apr 1991 21:20:52 GMT From: Syd Weinstein Newsgroups: comp.dcom.telecom Subject: Re: 56kbps Alternatives? Reply-To: syd@dsi.com Message-ID: Organization: Datacomp Systems, Inc. Huntingdon Valley, PA Sender: Telecom@eecs.nwu.edu 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 272, Message 6 of 11 Lines: 48 Mark McWiggins writes: > My prospective employer is using a leased line for 56kbps service > between two remote offices. I've read the blurb for UUNET's Alternet > service, and I got an e-mail note saying that PSInet offers something > similar. > Presumably either of these is much cheaper than a leased line, but > what would one be giving up by changing from a leased line to Alternet > or PSInet? Ok, as a user of a 56KB leased line to connect to PREPnet (our local NSFnet), I don't understand something here... If your employer has a 56KB leased line as DDS or DDS-II service between two offices, what is he running over it? (What protocol?) Is it a proprietary protocol between to multiplexers? an X.25 link? A TCP/IP link running SLIP?, TCP/IP running PPP? TCP/IP running something proprietary for the link? Straight sync data? The thing that Alternet and PSInet sell is a TCP/IP long haul service. You still need a 56KB leased line (or faster) to go from the local office to the nearest Alternet/PSInet Point of Presence and from the remote office to its nearset POP. The only savings I can see is if the link is long haul (remote offices are far away) and the cost of the PSI or Alternet is cheaper than the price of the direct 56KB line. Note, you would need a router at each end of the circuit, and the delay time would be longer under PSInet or Alternet, as in a private 56kb the delay is just two routers, with the network in place its your two routers + as many more as they use in making up their network. Now there is a big gain in connectivity outsite of the two offices, but just for a private link, its not apples and apples we are comparing here but apples and oranges. If you are looking at PSInet, Alternet, et al, time to also look at all the other long haul data networks, such as Sprintnet (nee telenet), Tymnet, Compuserve, and many many others. Sorry to be so long, but you are opening up an entire new direction to explore, not just replacing a simple 56kb data circuit. Sydney S. Weinstein, CDP, CCP Elm Coordinator Datacomp Systems, Inc. Voice: (215) 947-9900 syd@DSI.COM or dsinc!syd FAX: (215) 938-0235