Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!caen!ox.com!mudos!mju From: mju@mudos.ann-arbor.mi.us (Marc Unangst) Newsgroups: comp.dcom.modems Subject: Re: Any REAL advantage of Trailblazer V.32 over MultiTech V.32? Message-ID: Date: 30 Oct 90 23:10:14 GMT References: <298@twg.bc.ca> Organization: The Programmers' Pit Stop, +1 313 665 2832 Lines: 44 bill@twg.bc.ca (Bill Irwin) writes: > 9600 V.32 model which I believe will talk to any V.32 modem. My question > is simply, will this modem talk to the Trailblazers that seem to be so > popular with uucp sites at 9600, or does the TB use a proprietary method > of establishing the 9600 connection? Any V.32 modem will connect to a Telebit that supports V.32, in V.32 mode. However, Telebits also support the proprietary PEP protocol, which they only talk with each other. PEP is a half-duplex protocol that can reach REAL-WORLD throughputs of around 18,000bps. Unfortunately, not all the Telebit modems support V.32. Only the T2500 and T1500 support it; the T1000 and Trailblazer Plus only support PEP at 9600, and your Multitech modem won't be able to talk to them. If your UUCP neighbors have T2500s, then your MT modem will be okay; if your UUCP neighbors only have Trailblazer Pluses, then your MT modem will be worthless for 9600bps connections. > I have heard that the TBs are designed to work better in a uucp > environment. What, exactly, does this mean? That means that they impliment the UUCP 'g' protocol in hardware and spoof the UUCP processes at each end by talking 'g' to the computer, but talking PEP between themselves. This increases throughput dramatically. 'g' over V.32 seems to max out at around 800cps. 'g' between two Telebits in UUCP spoofing mode can go as high as 1500cps or so. Trailblazers also, incidentally, have similar spoofing capabilities for Xmodem, Ymodem, and Kermit. > I appreciate any non-drum beating, non-emotional, _objective_ advantages > of the TB over the MT, to assist in the decision process. Thanks. I'd definitely go with the T2500. They're going for around $900 now (probably less with volume discounts), and do much more than a plain V.32 modem will. Just about the only drawback of the T2500 is that the maximum supported interface speed is 19.2Kbps; this limits somewhat the maximum throughput possible with V.42bis compression. -- Marc Unangst | mju@mudos.ann-arbor.mi.us | "Bus error: passengers dumped" ...!umich!leebai!mudos!mju |