Path: utzoo!attcan!uunet!tektronix!percival!jamesd From: jamesd@percival.UUCP (James Deibele) Newsgroups: comp.dcom.modems Subject: Hayes 9600 sysop offer - a sour deal. Message-ID: <1394@percival.UUCP> Date: 10 Oct 88 06:52:09 GMT References: <8810081712.AA14615@ucbvax.Berkeley.EDU> Reply-To: jamesd@percival.UUCP (James Deibele) Followup-To: comp.dcom.modems Organization: Percy's UNIX, Portland, OR. Lines: 55 In article <8810081712.AA14615@ucbvax.Berkeley.EDU> DMG4449@RITVAX.BITNET writes: >Beware! The 9600 bps CCITT standard has not been set yet. I hear its going Actually, there are several, which is part of the problem. The V.29 standard is for 9600 bps one way, or for 4800 bps both ways. The V.32 standard is for 9600 bps both ways, and is the standard people knew was coming. (I'm speaking of bps rates over dial-up lines, as opposed to data lines. A typical dial-up line has two wires, a data line four.) The "bandwidth" of a typical voice line can vary dramatically, which is why Telebits, with their 512 channels and slow rate of fallback (if the line is bad, they start tossing out channels, lowering the bps. They keep testing the line to make sure they're getting the best rate. A typical 9600 like the Courier HST or V-Series Hayes drops from 9600 to 7200 to 4800 --- and doesn't adjust back up.) are popular on intercontinental hookups. The circuitry required to stuff 9600 bps down the line while getting it back at 9600 bps is expensive, with some recent V.32 modems finally reaching the $1300- $1500 price range. The latest wrinkle is compression schemes --- MNP claims 300% compression with their advanced MNP classes (7 or 9), but many of the manufacturers don't want to use them because of licensing fees. They use their own schemes. I've heard rumors of a "V.42" which will let the modems negotiate compression schemes, but haven't seen anything in print on it. Many modems which transmit at 9600 bps claim throughput of 14,000 bps (or higher) because they use such compression. The effectiveness of the compression varies with the type of data, and it's not a "true" faster bps, but if your data tends to get there in half the time it would if it wasn't compressed, who cares? >home users will turn towards the USR HST because hundreds of boards >across the nation use HST's, not to mention they are half the price of Hayes. I have to agree with you that the HST has become a "second standard" because of the USR sysop deal. Now that there seems to be the possibility of V.32 modems dropping under $1000 (street price) by the end of the year, however, I think competition will drive the price down fast. Not so fast as I'd like, but V.32's may become the standard by the end of next year. The real problem is what do you do with 9600 bps both ways? File transfers, the most common use of BBS modems, tends to be almost exclusively a one-way affair. Many people can't keep up with 2400 bps text, they're not going to be able to read 9600 bps text. Videotext applications, such as AppleLink or Prodigy, don't need the fast baud rate in both directions; many such systems use a 1200-bps channel to provide text and video to the viewer while providing a 75-bps channel for responses. An increasing (and logical) trend is to put the images on the disk, then send a control code that tells the software to "display menu A" or whatever, which creates the illusion of fast response time. Anyway, the Hayes modem offer, unless you get an iron-clad guarantee that you can upgrade to V.32, is simply the selling-off of a failed product. Buy it if you don't mind talking at 2400 bps to all the other 9600 bps modems out there. -- James S. Deibele jamesd@qiclab or jamesd@percival TECHbooks: The Computer Book Specialists (800) TECH-BKS 3646 SE Division Portland, OR 97202 (503) 238-1005 TECHbooks One BBS (#1:105/4.0); 3/12/24 (503) 760-1473