wfaust@venus.UUCP (Wolf Faust) (01/30/91)
In article <sJkiw2w162w@zooid>, Lima Bone writes: > ghost@bucsf.bu.edu (Jay Adelson) writes: > > Can someone please tell me what the difference between the standards > > v.32, v.32bis, v.42, v.42bis is? And which modems have which? (Between > > the Telebit and the USRobotics?) > Wayll, I think any modem with v.42bis has also v.32bis..I have a USRobotics > HST with v.42bis and it also has the capability of v.42bis...which I think > is merely the name of the data-compression that it uses. I could be wrong, > but that's what it looks like. V.32 9600BPS fullduplex V.32bis 14400BPS fullduplex HST 14400BPS halfduplex (well not really: 14400/450BPS) V.42 error correction protocoll V.42bis data compression protocoll Somebody wrote that there is no HST with V.32, but that's not true! As before, you still can buy a HST, V.32 and DualStandard. All modems now have V.32bis... ----- Wolf Faust UUCP:cbmvax.commodore.com!cbmehq!cbmger!venus!wfaust Tel: (+49)69 5486556 FIDO: 2:243/43.5
lron@uunet.uu.net (Dwight Hubbard) (01/30/91)
In article <sJkiw2w162w@zooid>, Lima Bone writes: > ghost@bucsf.bu.edu (Jay Adelson) writes: > > Can someone please tell me what the difference between the standards > > v.32, v.32bis, v.42, v.42bis is? And which modems have which? (Between > > the Telebit and the USRobotics?) > Wayll, I think any modem with v.42bis has also v.32bis..I have a USRobotics ^^^^^^^^^^^^^^^^^^^^^^^^^ No, they are two different types of standards > HST with v.42bis and it also has the capability of v.42bis...which I think > is merely the name of the data-compression that it uses. I could be wrong, > but that's what it looks like. V.32 is a modulation standard to get 9600 full duplex, it is supported by the Telebit T2500 and the USR Dual Standard. Both companies make V.32 only modems as well. V.32 modems from Intel and PP&S tend to be cheaper than either the Telebit or the USR V.32 modems. V.32bis is a modulation standard to get 14.4K full duplex, it is supported by the newer USR Dual standard modems as well as modems made by DigiComm. Final approval of V.32bis is not until next month, however it is not likely to change. V.42 is a standard for error detection/correction MNP levels 1-4 are a subset of V.42, allowing V.42 modems to use MNP error detection/ correction. This mode is supported by the Telebit T2500, the USR Dual Standard and the USR HST 14.4. It is supported by most newer V.32 modems by other companies as well. V.42bis is a standard for on the fly compression. It normally comes with V.42 error correction/detection. V.42bis allows a maximum compresion of 4:1 however like any other compression system it will not cause a very large increase in speed on compressed files, unlike MNP-5 it will not however increase the amount of data (slowing things down). This is supported by the Telebit T2500 and the USR Dual Standard and HST 14.4 modems. It is supported by most of the newer V.32 modems as well. -Dwight Hubbard USENET : uunet!easy!lron -Kaneohe, Hawaii CFR : 31:910/101 (Dwight Hubbard)
dave@unislc.uucp (Dave Martin) (02/02/91)
From article <1899b1ec.ARN13a0@venus.UUCP>, by wfaust@venus.UUCP (Wolf Faust): > In article <sJkiw2w162w@zooid>, Lima Bone writes: >> ghost@bucsf.bu.edu (Jay Adelson) writes: > >> Wayll, I think any modem with v.42bis has also v.32bis..I have a USRobotics >> HST with v.42bis and it also has the capability of v.42bis...which I think >> is merely the name of the data-compression that it uses. I could be wrong, >> but that's what it looks like. > > V.32 9600BPS fullduplex > V.32bis 14400BPS fullduplex > HST 14400BPS halfduplex (well not really: 14400/450BPS) > V.42 error correction protocoll > V.42bis data compression protocoll > > Somebody wrote that there is no HST with V.32, but that's not > true! As before, you still can buy a HST, V.32 and DualStandard. > All modems now have V.32bis... ^^^ ^^^^^^ our CIS dept. supra 2400 doesn't have V32.bis... 8-) Actually V32.bis is not a standard yet, the people I got my modem from refuse to add V32.bis (they are going to provide an upgrade path) until it is a finalized standard. Note you CAN buy modems today that have v32bis just like you could buy ansi-c compilers before ansi-c was a final standard. But in the event of some change, hardware is harder to upgrade than software. I agree with my modem vendor and am willing to wait until V32 IS a standard. Sorry to waver off of Amiga stuff here. -- VAX Headroom Speaking for myself only... blah blah blahblah blah... Internet: DMARTIN@CC.WEBER.EDU dave@saltlcy-unisys.army.mil uucp: dave@unislc.uucp or use the Path: line. Now was that civilized? No, clearly not. Fun, but in no sense civilized.