ralph@ralmar.UUCP (Ralph Barker) (02/19/89)
I am doing research on the question of "LANS vs. MULTI-USER SYSTEMS,"
and would like to get opinions from the Net.
Although the topic may sound like an invitation to start an off-line
flame war, what we are actually interested in is:
1. Under what circumstances/environments have you (or your
company) found a LAN (in this case, networked PCs) to be a superior
solution to the needs of the user community, compared to a
multi-user (UNIX or otherwise) system?
and, conversely,
2. Under what circumstances/environments have you concluded that
a multi-user system was the better choice?
Please send e-mail to me at the address shown below. I will summarize
if others are interested.
Thanks for sharing your thoughts.
--
Ralph Barker, RALMAR Business Systems, 640 So Winchester Blvd, San Jose,CA 95128
uucp: ...{pyramid, sun, uunet}!amdahl!unixprt!ralmar!ralph
or, attmail!ralmar!ralph Voice: (408) 248-8649jc58+@andrew.cmu.edu (Johnny J. Chin) (02/20/89)
Fellow readers:
First, I'd like to make it clear that what I state here are strictly my own
opinion. Please DO NOT flame or gripe about it.
In general, if you are going to have a lot of users, you will probably be
better off with a LAN.
The other reason for using a LAN is if you are running a lot of PC software,
then going to a LAN will cost less than having all the data converted to some
MULTI-USER operation system and having the users learn the new software.
A combination of the two may not be a bad idea. Well, it only applies to the
MS-DOS/Netware environment. What I mean is ... Have a 386 computer run
PC/MOS-386 and have the Netware Multi-user driver running on it. This way, you
can dump off several terminals (ie. Wyse 50, Televideo, etc.) from the 386
and have each one of the terminals act as if it was an actual computer (some-
what similar to a multi-user setup) and yet access data and resources similar
to that of a LAN.
If you are starting a new setup and currently use lots of MS-DOS software, the
combination method may be you cheapest method.
If you are using a UNIX or VMS operating system then a multi-user setup will
probably be the better choice (I maybe wrong, thou).
[Aside: I am particularly better knowledged with MSDOS than anything else.]
-- J. Chin (a.k.a. Computer Dr.)
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xxxxxxxxxx Smile! -- Mr. HappyWOWface -- (got this from the network)
Disclaimer: The views expressed herein are STRICTLY my own, and not CMU's.john@stiatl.UUCP (John DeArmond) (02/20/89)
In article <471@ralmar.UUCP> ralph@ralmar.UUCP (Ralph Barker) writes: > >I am doing research on the question of "LANS vs. MULTI-USER SYSTEMS," >and would like to get opinions from the Net. > Ralph, Actually you should not look at it as "multiuser vs lans" - it should be "multiuser AND lans". This brings into the picture the whole concept of distributed processing. Consider a couple of examples: A couple of years ago, I created a telephone operator system around a network (Novell in this case) of PCs. Each operator workstation was a cheap clone configured as a diskless workstation. The clone ran one part of the application - the user interfase and so on. We built a rate server (calculated the cost of a call; ie "rate") on a compaq 386 box. This server services all the workstations via a peer-to-peer protocol. Other boxes implemented other servers. One 386 could handle over 75 workstations at a time because the user interface code was executed on each workstation. If more users came on line, so did more cpu power. This is an example of multiuser but not multitasking, for the most part. Another example. In our current software development environment, we have a myrid of machines linked via ethernet. This includes PCs, VAXs, Unix systems and several SUN 386i's. The Suns in particular, demonstrate what can be done with multiuser AND lans. Even though the development of the environment is in it's infancy, already jobs can be dispatched to the cpu with the lowest load or multiple cpus can be put to work on the same job. This means that I can, for example, push a compile off onto anohter Sun which at the moment is lightly loaded and continue working with full response speed on my machine. Another aspect that most PC users can't even start to appreciate is an integrated Email system. This to me is perhaps one of the strongest features of Unix. At the highest level, people on our team can communicate effortlessly and without having to all be available at once. At a lower level, since mail is built into standard Unix, a program can use it to, for example, send error messages to the user and an administrator or tech support system. This is especially revelant for programs that run on off- hours. Like backups, for instance. This process can send Email confirming either success or failure. consider another example. If we have a developer whos needs will not load a sun too heavily, we can buy a relatively cheap X terminal and hang it on the ethernet. It uses a specified Sun as its cpu. Then if the load develops to the point that response degrades, we can buy another cpu for that user. Thus you can bootstrap another work station up for very little initial cost and delay the large purchase of another CPU until the workload justifies it. Hope this helps a bit. john -- John De Armond, WD4OQC | Manual? ... What manual ?!? Sales Technologies, Inc. Atlanta, GA | This is Unix, My son, You ...!gatech!stiatl!john | just GOTTA Know!!!
karl@ddsw1.MCS.COM (Karl Denninger) (02/21/89)
I was going to mail this, but then realized that there have to be others out there that can use this kind of advice. Of course, it's worth what you pay for it coming off the net :-) In article <UXzmFqy00WI5QJ5Zkm@andrew.cmu.edu> jc58+@andrew.cmu.edu (Johnny J. Chin) writes: >Fellow readers: > >First, I'd like to make it clear that what I state here are strictly my own >opinion. Please DO NOT flame or gripe about it. > >In general, if you are going to have a lot of users, you will probably be >better off with a LAN. Unless you're going to pay the bill for that LAN...... (no smiley folks!) Think local area network with reasonable performance. This means an AT on every desk, with some form of (small) local fixed disk to get reasonable speed on most of the I/O (system programs). Assuming $1200 per AT, you get: o $1200 (AT compatible) o $200 (Fixed disk for the AT, 20MB) o $250 (Adapter board, WD Ethernet, for the AT) This brings your cost per station, independant of cable factors, to nearly $1700 per station, and you haven't purchased a server yet! Let's take a small network: 10 stations @ 1700 per 17,000 1 Big File Server (300MB or so) 10,000 ------ 27,000 Each additional station adds $1700 to the cost (OUCH!). Now, Multiuser on the same size setup: o One big fast honking '386 system w/Unix or Xenix $15,000 (This assumes a _DECKED_ machine; 25Mhz, ESDI disk, tape, math processor, etc). o 10 Terminals @ 500 per (WY85 or equivalent) 5,000 ------- $20,000 This leaves you seven thousand dollars to play with to up the performance of that nice Multiuser system! As an example, we could spend the $7k outfitting the Unix machine with Sun River Fiber optic EGA workstations instead of some of the terminals....... and now you have EGA PC capability as well as a nice color display for the Unix programs! Larger systems have similar cost/performance differences. PC Ethernet's biggest limitation is in the I/O channel capability of the present cards. They just don't perform like a VAX on the ether, and trying to make them do so will damage your pocketbook real quick! Now, this assumes a typical workload (office-type work). If you already own the PC's, then the entire situation changes (since you already _have_ the expensive parts). In that situation it may be less expensive to go with the LAN. Note that the LAN system generally doesn't come with much in the way of useful software out of the box, while a Unix machine certainly does (mail, communications software, compiler(s), text procesisng, etc). Remember, too, that a DOS-based solution will only give you single-tasking processing. A multiuser solution allows multiple windows or jobs per terminal; both VMS and UNIX machines can do this with relatively little effort....... There is no one "right" answer. Factors such as the three guys who need to run DOS CAD packages tend to make the decision easy -- but when there is no such requirement, the choice tends to come down to a matter of economics. Study your requirements in detail before you make a decision, and consult a professional if you're not sure which way to turn. There's enough money involved in these system installations that a few hundred dollars spent on a pro's time and expertise is well worth the possibly heartburn you may endure if you "roll your own". One quick note: Lots of LAN salesmen sell you a LAN based on the "superior fault tolerance". Well, unless you buy two servers, if you load your LAN like most people (software & especially data goes on the server disks) you're screwed if the server crashes anyways! Don't buy that argument -- both Multiuser and LAN approaches can be single-point failed, and BOTH can have this possibility circumvented (at horrendous additional cost). -- Karl Denninger (karl@ddsw1.MCS.COM, ddsw1!karl) Data: [+1 312 566-8912], Voice: [+1 312 566-8910] Macro Computer Solutions, Inc. "Quality solutions at a fair price"