bjahn@wam.umd.edu (Guess ??? ) (04/16/91)
I am wondering about the various 9600 modems. Escpecially the US Robotic modems. What is the difference between the USR v.32 modems and the HST modems? In general, what is the standard in 9600 modems, and is there much difference in int/ext modems beside personal preference? What is difference between v32, v32.bis, v42, v42.bis and MNP5? What would be a good buy for a modem that won't be outdated or will be off standard in the future? Thanks in advance!
edm@hpfcmdd.hp.com (Ed Moore) (04/19/91)
> What is difference between v32, v32.bis, v42, v42.bis and MNP5?
I've been collecting info on such modems in anticipation that some day I'll
be using them. Here are some useful descriptions of modem terms and
technology.
10/16/90 PC Magazine, page 102
10/29/90 InfoWorld, page 91
12/11/90 PC Magazine, page 312
12/25/90 PC Magazine, page 449
2/12/91 PC Magazine, page 23
3/26/91 PC Magazine, page 218fenger@galaxy.cps.msu.edu (Steven V Fenger) (04/20/91)
In article <1991Apr19.141045.113@gnv.ifas.ufl.edu> sjs@gnv.ifas.ufl.edu writes: >From: bjahn@wam.umd.edu (Guess ??? ), >University of Maryland at College Park > >>I am wondering about the various 9600 modems. Escpecially the US Robotic >>modems. What is the difference between the USR v.32 modems and the HST modems? >>In general, what is the standard in 9600 modems, and is there much difference >>in int/ext modems beside personal preference? >> What is difference between v32, v32.bis, v42, v42.bis and MNP5? >>What would be a good buy for a modem that won't be outdated or will be off >>standard in the future? >> Thanks in advance! > > >All I know (others will have to fill in the blanks): > >V.21: CCITT standard for 300 bps modems. >V.22: CCITT standard for 1200 bps modems. >V.22 bis: CCITT standard for 2400 bps modems. >V.32: CCITT standard for 9600 bps modems. V32.bis: CCITT standard for 14.4Kbps. I'm not sure this is truely an official standard yet. V42: CCITT standard for error correction. Includes LAP-M and fallback to MNP1-4. V42: CCITT standard for on-the-fly data compression. Smarter than MNP5, it doesn't try to compress already compressed data. >MNPx: MNP = Microcom Networking Protocol, a modem error-correction > protocol. Modem manufactures must license MNP standards from Microcom in order to use them. MNP1-4 is reasonable and is almost public domain. MNP5 is more expensive. MNP7 & 9 is outragously priced so V42bis will dominate. >CCITT: Consultative Committee International Telegraph and Telephone. > An organization established by the United Nations to develop > worldwide standards for communications technology. A US Robitic's HST modem is a 14.4Kbps/450bps async channel modem and is not compatible with V32. V32 does 9600bps in both directions. US R. does offer the "DualStandard" which has both HST & V32 compatability. What won't become obsolete? At this point the only thing I can see that is obsolete is V32 modems. V32bis is coming out real soon. Of course, V32bis will cost more than V32 and a V32 modem can connect to a V32bis modem. As to HST vs V32 it depends on who you call. Most IBM-related BBSes use HST modems because sysops can get a great deal on one. V32(bis) is a world-wide standard, though, and for all types of computers. The unix world generally use Trailblazer modems with PEP standard (an async channel modem like the HST.) Steven Fenger fenger@frith.egr.msu.edu \ fenger@cps.msu.edu > But all roads lead to fenger@galaxy.cps.msu.edu fenger@power1.ee.msu.edu /