sz@cci632.UUCP (Stephen Zehl) (04/26/89)
- I'm holding an advertisement from Microcom for their new V.32 modem that they claim runs at 38,400 bps in MNP Class 9. A little asking around and I found that they list at $1395.00 and we can get them for as little as $800.00!!!!! What's the story here?? Anyone have these, know about these, ever used one?? Any and all information would be appreciated. Is this the END for TELEBIT TRAILBLAZERS! We could save over $120.00 each buying these, and save a bundle on phone costs to boot. Maybe Telebit would like to comment on no longer having the fastest/cheapest modem around???? (I know telebit is out there, they post every so often). E-Mail or Follow-up, Thanks all. Steve. CCCC CCCC IIII Stephen Zehl UUCP: sz@cci632.UUCP CC CC II Computer Consoles. Inc. Csnet: cci632!sz@cs.rochester.EDU CC CC II Rochester, New York. Usenet: rutgers!rochester!cci632!sz CCCC CCCC IIII DISCLAIMER: I speak for myself, not for my employer.
syd@dsinc.DSI.COM (Syd Weinstein) (04/27/89)
In article <28111@cci632.UUCP> sz@cci632.UUCP (Stephen Zehl) writes: >- > I'm holding an advertisement from Microcom for their new V.32 modem >that they claim runs at 38,400 bps in MNP Class 9. A little asking around >and I found that they list at $1395.00 and we can get them for as little as >$800.00!!!!! > Is this the END for TELEBIT TRAILBLAZERS! We could save over >$120.00 each buying these, and save a bundle on phone costs to boot. This ones easy. If you feed the mnp 9 v.32 modem uncompressed restricted ascii source which it can compress to the limit, it can indeed approach 38.4bps throughput using a long block protocol. Note, uucp's protocol with its short packets doesn't lead to packing the data stream quite so well. However, and the big however, is that we currently send compressed batched over the tb+'s for news. Now the underlying rate of a v.32 is 9600 cps. The underlying rate of a tb+ is at best 14000-18000 cps, again faster than the v.32. The tb+'s sending uncompressed ascii can easily do 19200cps and could do even faster if telebit would make a rom change and allow 38400 to and from the modem. (Current top interface rate is 19200) Thus for uucp, and compressed news transmission, the tb+ is still a higher throughput modem. About 1.3 to 1.4 times faster. For restricted character set ascii, the mnp9 v.32 will be faster, but how much data do you send that way and how much is compressed? -- ===================================================================== Sydney S. Weinstein, CDP, CCP Elm Coordinator Datacomp Systems, Inc. Voice: (215) 947-9900 syd@DSI.COM or {bpa,vu-vlsi}!dsinc!syd FAX: (215) 938-0235
condor@mas.UUCP (Rick Kawala) (04/27/89)
In article <28111@cci632.UUCP>, sz@cci632.UUCP (Stephen Zehl) writes: > - > I'm holding an advertisement from Microcom for their new V.32 modem > that they claim runs at 38,400 bps in MNP Class 9. A little asking around > and I found that they list at $1395.00 and we can get them for as little as > $800.00!!!!! > I know that Telebit has special requirements if you want to buy their modems at a discount (i.e. you need to have a second-level domain). What does Microcom require to get the $800 price, or are you just getting a good price from a distributor somewhere? If so, who is the distributor? Thanks in advance, Rick Kawala apple.com!mas1!condor Contracted to Measurex Automation Systems
ram@tslanpar.UUCP (R. Meesters, Tech Support, Lanpar Toronto Ontario Canada) (04/28/89)
In article <28111@cci632.UUCP>, sz@cci632.UUCP (Stephen Zehl) writes: > - > I'm holding an advertisement from Microcom for their new V.32 modem > that they claim runs at 38,400 bps in MNP Class 9. A little asking around > and I found that they list at $1395.00 and we can get them for as little as > $800.00!!!!! > > What's the story here?? Anyone have these, know about these, ever > used one?? Any and all information would be appreciated. > I don't know about price, since we don't deal in real dollars up here :-} The modem does data transfer at 9600 baud, but uses the MNP data compression algorithms (Class 9 being the most recent) to achieve high speeds. I haven't tried the QX, but the 9624's I have running V.29 with MNP class 6 can hit around 15,000 bps flat out on a 19,200 bps line, so I wouldn't doubt that full duplex V.32 is capable of speeds approaching 38,400. -- ------------------------------------------------------------------------------ Richard Meesters | Lanpar Technologies Inc. | "Calling YOU stupid would Toronto, Ontario | be an insult to stupid people" ...attcan!nebulus!tslanpar!ram | - A Fish Called Wanda ------------------------------------------------------------------------------
caf@omen.UUCP (Chuck Forsberg WA7KGX) (04/28/89)
In article <28111@cci632.UUCP> sz@cci632.UUCP (Stephen Zehl) writes:
:-
: I'm holding an advertisement from Microcom for their new V.32 modem
:that they claim runs at 38,400 bps in MNP Class 9. A little asking around
:and I found that they list at $1395.00 and we can get them for as little as
:$800.00!!!!!
:
: What's the story here?? Anyone have these, know about these, ever
:used one?? Any and all information would be appreciated.
Pro-YAM, ZCOMM and DSZ will get about 25,000 "baud" throughput on a 2400
bps line sending the Personal Computing Magazine ASCII Benchmark file
with compression. MNP/9 should do nicely sending this file also.
I can guarantee neither will do as well sending compressed, batched news!
The raw throughput on a 2400 bps line is 300 characters per second
(synchronous). Likewise 9600 has a raw throughput of 1200 cps. Since
the higher levels on MNP use synchronous transmission, the 300 and 1200
cps speeds can be approached. Any higher speeds are obtained by
compression in the modem or file transfer protocol. BOth MNP/9 and
the latest TrailBlazer models feature compression, which is effective
on text files but not on compressed news, etc.
What affordable V.32 modems indicate is the presence of a non proprietary
full duplex standard >2400 bps on regular dialup lines. This does
create a new ballgame. That's why Telebit is tacking a Rockwell V.32
chip set onto their latest modem to become "more compatible" (read "more
competitive in the marketplace.").
Chuck Forsberg WA7KGX ...!tektronix!reed!omen!caf
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
Omen Technology Inc "The High Reliability Software"
17505-V NW Sauvie IS RD Portland OR 97231 503-621-3406
TeleGodzilla:621-3746 FAX:621-3735 CIS:70007,2304 Genie:CAFjqj@oregon.uoregon.edu (JQ Johnson) (04/29/89)
In article <118@dsinc.DSI.COM>, syd@dsinc.DSI.COM (Syd Weinstein) writes: > Thus for uucp, and compressed news transmission, the tb+ is still > a higher throughput modem. About 1.3 to 1.4 times faster. > > For restricted character set ascii, the mnp9 v.32 will be faster, > but how much data do you send that way and how much is compressed? Has anyone done any evaluation of v.32 + MNP-9 for TCP/IP SLIP traffic? I am interested in thruput for large packets, but also in behavior for small packets (e.g. 60 to 150 bytes typical of telnet traffic). In that realm, most of the packet is binary header and is mostly the same from packet to packet. We care less about throughput than about latency: a modem that takes 50ms to do the compress/mod/demod/decompress adds 100ms to RTT on a link.
leonard@bucket.UUCP (Leonard Erickson) (04/30/89)
In article <28111@cci632.UUCP> sz@cci632.UUCP (Stephen Zehl) writes:
<-
< I'm holding an advertisement from Microcom for their new V.32 modem
<that they claim runs at 38,400 bps in MNP Class 9. A little asking around
<and I found that they list at $1395.00 and we can get them for as little as
<$800.00!!!!!
What the deal is, is that using MNP class 9 most mfgs *claim* 4-1
compression of the data by the modem. I bet that if you tried running
a compressed newsfeed thru them, you'd be lucky to get 9600!
Whereas with a Trailblazer you get 18,000 bps wityhout compression.
With compression you get even better results.
--
Leonard Erickson ...!tektronix!reed!percival!bucket!leonard
CIS: [70465,203]
"I'm all in favor of keeping dangerous weapons out of the hands of fools.
Let's start with typewriters." -- Solomon Shortrja@edison.GE.COM (rja) (05/07/89)
In article <151@tslanpar.UUCP>, ram@tslanpar.UUCP (R. Meesters, Tech Support, Lanpar Toronto Ontario Canada) writes: > I don't know about price, since we don't deal in real dollars up here :-} > The modem does data transfer at 9600 baud, but uses the MNP data compression > algorithms (Class 9 being the most recent) to achieve high speeds. Precisely. The key thing for folks to keep in mind is that MNP compression will not work properly on material that has already been compressed (such as USENET news, etc.) so for those types of transfers you'll only get the 9600 bps transfer rate. The TB will transfer compressed material at up to 18000 bps. I find locally that I am getting around 16K of bandwidth on a Telebit T2000, but our phone lines are notoriously bad... The Telebit T2500 does have V.32 and MNP among other modes.