akcs.larry@nstar.UUCP (Larry Snyder) (11/14/89)
According to this week's Infoworld - USR will be adding V.42 to their current crop of high speed modems effective January 1. So now the USR HST will talk to the Hayes V-Series modems - and the dual standard will be HST/V.42/V.32 plus 300/1200 and 2400 baud. Prices for the upgrade are $50 if the modem was purchased prior to October 1, - or free if after.
bourman@hpccc.HP.COM (BobbHewlett-PackardCorpNetEngPaloAltoCa.) (11/16/89)
/ hpccc:comp.dcom.modems / akcs.larry@nstar.UUCP (Larry Snyder) / 6:25 pm Nov 13, 1989 / >According to this week's Infoworld - USR will be adding V.42 >to their current crop of high speed modems effective January 1. > >So now the USR HST will talk to the Hayes V-Series modems - >and the dual standard will be HST/V.42/V.32 plus 300/1200 and >2400 baud. > >Prices for the upgrade are $50 if the modem was purchased prior >to October 1, - or free if after. >---------- Is thei V.42 or V.42bis ???? V.42 is being replaced with V.42bis and I wouldn't waste my time on just V.42 error correction. BOBB
akcs.larry@nstar.UUCP (Larry Snyder) (11/18/89)
> Is thei V.42 or V.42bis ???? V.42 is being replaced with V.42bis and I > wouldn't waste my time on just V.42 error correction. The news release didn't mention anything about V.42bis - only V.42.
logic@wet.UUCP (Henry Kwan) (11/21/89)
In article <5830004@hpccc.HP.COM> bourman@hpccc.HP.COM (BobbHewlett-PackardCorpNetEngPaloAltoCa.) writes: > > Is thei V.42 or V.42bis ???? V.42 is being replaced with V.42bis and I > wouldn't waste my time on just V.42 error correction. > > > BOBB According to the InfoWorld article, USR is upgrading the HSTs to v.42bis. The article goes on to state that v.42bis is suppose to perform up to 30% better than v.42. Which still doesn't tell us if having compression on while transmitting LZHed/ZIPed files will do us any good. Oh well. I am having trouble connecting in v.32 with a USR Dual Standard to a Telebit T2500. Does anyone know which S-register might be fiddled with to provide better results? -- Henry Kwan | AppleLink: D0690 FWB, Inc. | CompuServe: 71320,1034 2040 Polk St. Ste 215 | Internet: claris!wet!logic@ames.arc.nasa.gov San Francisco, CA 94109 | UUCP: {claris,hoptoad,lamc,ucsfcca}!wet!logic
ch@maths.tcd.ie (Charles Bryant) (11/22/89)
V.42 is error correction V.42bis is compression (intended to run with V.42) -- Charles Bryant. (ch@dce.ie) Working at Datacode Electronics Ltd. (Modem manufacturers)
necka@cell.mot.COM (William J. Necka) (11/22/89)
In article <5830004@hpccc.HP.COM> bourman@hpccc.HP.COM (BobbHewlett-PackardCorpNetEngPaloAltoCa.) writes: >/ hpccc:comp.dcom.modems / akcs.larry@nstar.UUCP (Larry Snyder) / 6:25 pm Nov 13, 1989 / >>According to this week's Infoworld - USR will be adding V.42 >>to their current crop of high speed modems effective January 1. >> >>So now the USR HST will talk to the Hayes V-Series modems - >>and the dual standard will be HST/V.42/V.32 plus 300/1200 and >>2400 baud. >> >>Prices for the upgrade are $50 if the modem was purchased prior >>to October 1, - or free if after. >>---------- > > > Is thei V.42 or V.42bis ???? V.42 is being replaced with V.42bis and I > wouldn't waste my time on just V.42 error correction. > > > BOBB It is V.42bis. V.42 is as you say an error correcting protocol which has LAP as its primary method and MNP as a secondard. This means that V.42 complient modems can talk to both hayes and every one else. But be warned that V.42 compatable does not mean complient. All LAP and MNP modems are V.42 compatable, but only V.42 complient modems will work with both LAP and MNP modems. V.42bis is a data compression method that was put in the V.42 and is based on the LZ method. It offers better compression through-put and is not as processor resource intensive. That means that can potentially be run on a low cost micro like the 8051 z80 or maybe even a z8. That can not be said about MNP7. That algorithm requires alot of processor resources. V.42bis also has some smarts built into it. Unlike MNP5 it has selective repeat. If a block is found to be in error then only the NAKed block is resent. MNP recends the NAKed block plus any blocks it managed to send before the block was NAKed. This does not come without cost, and so you will find that all V.42/V.42bis modems come with a larger ram chip; probably 32K bytes or bigger. The extra ram is needed because unlike MNP, you must keep a copy of all blocks sent untill they are ACKed. The compression tables for V.42bis also eat up alot of ram. P.S. For those of you with newer USR HSTs or Dual Standards or USR V32s , type the following command in: ATUSR<cr> You will get a kick out of the response the modem gives you. Have fun modeming.