HDTenEightyP/NetNews huggingface dataset:
From: nason@pa881a.inland.com
Newsgroups: comp.dcom.lans.ethernet
Subject: Re: what is SQE  (DUMB QUESTION!)
Date: 27 Aug 92 13:42:00 GMT
Organization: Inland Steel Company, East Chicago, IN

In article <1992Aug25.202024.4870@hubcap.clemson.edu>, cballen@hubcap.clemson.edu (charles allen) writes:
> Sorry for asking such a stupid question.
> We have an AUI to Thinwire thing for a Decstation server
> in a 30 DOS machines lab setting.  There is a jumper on the box to turn
> SQE on or off.  I've never heard of SQE before.
>  
> The server has 2 AUI ports, one to the backbone thickwire, and the other
> to  the lab thinwire.  The server is on it's own segment to the lab
> repeater.  I just saw a posting mentioning SQE, and I thought I'd ask.
-- 
No, this is not a dumb question. It causes a great deal of confusion, even
among the experts.  SQE is the Signal Quality Error. It is a signal sent by the
MAU, your thing, to the DTE, your node.  The signal is intended to tell the
node that there has been a collision.  

The switch on your box is in reality a switch to turn off the SQE *test*. 
This test is performed after each transmission to test the collision detect
circuitry.  Each MAU under 802.3 must be have a provision to manually turn off
the SQE test.  This is done for a variety of reasons.  If the MAU is connected
to a repeater, or if the MAU is connected to a Ethernet V2 device.  

One of the differences between 802.3 and ethernet V2 is the collision detect
circuitry test.  Under Ethernet it is called the Collsion Presence Test.  Under
802.3 it is called the SQE test.  In your appliction, you want SQE test turned
on.    

My opinions are my own and not those of my company.  
Free advice is worth its cost.  
--- John M. Nason - NA9U ---|--------------------------------------------|
Inland Steel Company        |  -- nason@pa621a.inland.com                |
Process Automation MS 2-464 |  -- Fax:   219-399-7856                    |
3210 Watling Street         |  -- Voice: 219-399-2450                    |
East Chicago IN 46312       |"Ya can't shoot em till they stop sparklin" |
----------------------------|--------------------------------------------|
Newsgroups: comp.dcom.lans.ethernet
From: opus@pioneer.unm.edu (Colby Kraybill)
Subject: Re: Traffic Visualization tool?
Date: Tue, 01 Sep 92 17:09:08 GMT
Organization: Space and Planetary Image Facility

In <1992Aug27.230732.7020@rpslmc.edu> bwolfe@rad.rpslmc.edu (Brian A. Wolfe) writes:

>For example, one way to show this graphically might be to 
>depict the network map (I need to show about 50 hosts at once)
>with icons representing the hosts, and then draw lines between the 
>hosts in real-time that get thicker (and thinner) based on the 
>volume of traffic between them. 

There are several packages of this sort around.  UltraNET produces systems
that are meant to do just network monitoring in such a fashion.  I believe
that NCD also produces such a package.



-- 
Colby Kraybill
Space and Planetary Image Facility
University of New Mexico
opus@pioneer.unm.edu
Xref: sparky comp.dcom.lans.ethernet:1776 comp.protocols.ibm:698
From: yates@gaia.cs.umass.edu (David Yates)
Newsgroups: comp.dcom.lans.ethernet,comp.protocols.ibm
Subject: Ethernet boards for PC's
Date: 31 Aug 92 20:23:05 GMT
Reply-To: yates@gaia.cs.umass.edu (David Yates)
Followup-To: comp.dcom.lans.ethernet
Organization: University of Massachusetts, Amherst

Dear Ethernet gurus:

  I'm looking for an Ethernet board for a PC clone.  We are building
an embedded system, which I want to communicate with from a PC.  The
system will have multiple modules that are distributed within a
single facility.  My requirements for the board are ...

  1) access to Ethernet at a fairly low level like
     a) an API that supports primitives like send/receive packet, 
       *OR*
     b) enough hardware documentation so that I can write my own
        driver for the board
  2) knowledge of Ethernet chip set used by the board vendor (I have
        a slight preference for AMD)

  Also, I understand that you can buy a block of 2**24 Ethernet
addresses from the IEEE standards office for $1000.  Do they also
handle the manufacturer IDs that go in the Ethernet type field?  Is
there an additional fee for a registered Ethernet type field?

  Any recommendations are greatly appreciated.  I will be happy
to summarize replies and post the summary.

  Thanks in advance,
    David

----------------------------------------------------------------------------
Mail:     David Yates                             Phone:  413-545-3179
          Dept of Computer Science - LGRC A243    FAX:    413-545-1249
          University of Massachusetts             E-mail: YATES@cs.umass.EDU
          Amherst, MA 01003
Newsgroups: comp.dcom.lans.ethernet,comp.dcom.lans.misc,comp.protocols.novell
From: seifert@netcom.com (Rich Seifert)
Subject: Re: 802.3 Non-Compliance (?)
Date: Mon, 31 Aug 92 20:32:20 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest) 
Followup-To: comp.dcom.lans.ethernet

In article <1992Aug28.194558.4752@iplmail.orl.mmc.com>, more@tcc.orl.mmc.com () writes:
> In this meeting (which unfortunately I wasn't in), the vendor made the statement
> that Netware Servers violate the 802.3. His statement was that when a netware
> server detects a collision, that rather than following the random backoff, 
> in the Ethernet world, the Netware server immediately attempts to retransmit
> the collided packet(after sending the jam sequence). This vendor stated that
> because of this, TCP/IP based systems running on the same ethernet as Novell
> netware servers could experience some performance problems due to the 
> noncompliant nature of the netware server. He further stated that for this
> reason, NASA has put a ban on Novell Netware at it's sites. 
>

I agree with you, this is a lot of BS. A NetWare server uses the same
controller hardware as anyone else; Novell has long been out of the
NIC business. The backoff algorithm is implemented in the silicon on the
NIC, and there is very little that NetWare can do about it.

Now, it is true that older releases of NetWare used the 802.3 MAC
without using the 802.2 Logical Link Control. This "strictly"
violates the 802 specifications, but has nothing at all to do with
hogging the wire through manipulation of the backoff algorithm.

In any case, current releases of NetWare (2.2, 3.11, etc.) fully
support 802.2.
 
-- 
Rich Seifert                    Networks and Communications Consulting
seifert@netcom.com              (408) 996-0922
                                (408) 996-2860 FAX
"... specialists in Local Area Networks and Data Communications systems"
Newsgroups: comp.dcom.lans.ethernet
From: doug@isuee1.ee.iastate.edu (Doug Jacobson)
Subject: Wanted: device driver for DP83932
Keywords: DP93932
Organization: Iowa State University, Ames IA
Date: Fri, 28 Aug 1992 17:15:00 GMT

I'm looking at using the National DP83932 for an Ethernet project and
I was wondering if:

1.  Has any one else used one and can make recomendations?

2.  Is there any PD device drivers or other software for the 83932?

3.  Should I use something else.

Doug Jacobson
From: seifert@netcom.com (Rich Seifert)
Newsgroups: comp.dcom.lans.ethernet
Subject: Re: Max Repeaters/multiport repeater wiring questions
Date: 4 Sep 92 01:37:45 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest)

In article <id.JIUS.UG6@ferranti.com>, kunkee@ferranti.com (randy kunkee) writes:
> In article <c8dnaah.seifert@netcom.com> seifert@netcom.com (Rich Seifert) writes:
> [ stuff deleted]
> >A thin-wire to fiber converter may or may not be a repeater, depending on
> >the way in which it is implemented. A multiport transceiver (e.g., DEC
> >DELNI) is NOT a repeater.
> >
> 
> Wouldn't you still count this as a repeater when calculating distances
> between systems?  Eg.:
> 
> VMS----DELNI---transceiver===coax===transceiver---DELNI---VMS
> 
> The two VMS systems above should be counted as having two repeaters
> (the DELNIs) between them, yes?
> 
In terms of cables, yes, all of the cables shown above must be counted
in the propagation delay budget. However, a repeater introduces
additional delay, due to its internal state machine. A repeater
retimes the signal, where a DELNI does not. An Ethernet configuration
must meet the rules for propagation delay, AND maximum number of
repeaters in tandem. For theis latter rule, you do not need to 
count the DELNI as a repeater (in fact it is NOT one).

-- 
Rich Seifert                    Networks and Communications Consulting
seifert@netcom.com              (408) 996-0922
                                (408) 996-2860 FAX
"... specialists in Local Area Networks and Data Communications systems"
Newsgroups: comp.dcom.lans.ethernet
From: bharat@ccvax.ucd.ie
Newsgroups: comp.dcom.lans.ethernet
Subject: compare between socket based and RPC based.
Date: 25 Aug 92 13:56:13 GMT
Organization: University College Dublin

Hi Net Gurus,
 
could any one tell me the advantages of "Socket Based interprocess
communication" over "Remote Procedure Call based interprocess communication"?

My application program runs on the top of the packet layer. It communicates 
with a X.25 switch. The communication between switch and application programm
is based on 'BSD Socket based communication'.

I summarize it in the following steps- 

1. I open a socket in X.25 domain (i am using SunNet X.25 software).

2. Pass the address of remote switch to the socket.

3. send some data (e.g. 'stat' command for the switch which gives all the 
statstical information from the switch). 

4. receive the output (e.g. output of 'stat' command which is parameter values 
from the switch).

             ----------------------------------------------------------

My questions are: 

1.why and when the socket based communication is used?

2.Why always RPC based communication is prefered over socket based 
communication is prefered?

3. Is it possible to implement a 'Client-Server' model using  sockets? if yes,
can i call 'My-application-program=X.25-switch' (as given in steps 1-4) as
a 'cleint=server' model?


Any pointers/hints..? Thanks very much for reading this. I will welcome any
concern information.

Please ..send your answers by email to me.

- Bharat

(bharat@ccvax.ucd.ie)
  
Newsgroups: comp.dcom.lans.ethernet,comp.dcom.lans.misc,comp.protocols.novell
From: anthony@csd4.csd.uwm.edu (Anthony J Stieber)
Subject: Joke, optional read (Re: 802.3 Non-Compliance (?))
Organization: Computing Services Division, University of Wisconsin - Milwaukee
Date: Thu, 3 Sep 1992 05:48:42 GMT

In article <1992Sep1.184819.11989@qiclab.scn.rain.com> 70465.203@compuserve.com writes:
>Q: What's the difference between a used-car salesman and a computer 
>   salesman?
>A: The used-car salesman *knows* when he's lying.

and he probably knows how to drive :-).
--
<-:(= Anthony Stieber	anthony@csd4.csd.uwm.edu   uwm!uwmcsd4!anthony
Newsgroups: comp.dcom.lans.ethernet
From: makela@noknic.nokia.fi (Kari M{kel{/NTC)
Subject: Re: Max Repeaters/multiport repeater wiring questions 
Organization: Nokia Group
Date: Wed, 26 Aug 1992 20:07:21 GMT

In article <1992Aug21.172813.1606@ra.royalroads.ca> bbaskett@post.RoyalRoads.ca (Bill Baskett) writes:

>3) Which is the correct way to wire a thinnet segment into a 
>   multiport repeater?
>  
>   a)                                  b)
>  
>    .------------.                       .--------------.
>    | mpr box    |                       | mpr box      |
>    `---.--------'                       `----.---------'
>        |                                     |
>    |---T--------------|                      |
>                                              |
>                                              -     <-terminator
>    (two terminators, t-connection        (one terminator, direct bnc
>     to multiport repeater)                connection to multiport repeater)

It depends on the box and on it's jumpering.  Two examples: Digital's
DEMPR has an internal terminator. i.e. b) is correct for it.  3COM's
Multiconnect has a jumper which connects/disconnects the internal
terminator; as far as I remember it comes shipped so that a) is correct
for it.  If you are not sure for a specific case, just simply measure
the DC resistance of the input.  If it is 50 ohms, use b).  If it is
infinite, use a).

>4) Can a transceiver be plugged directly into the workstation, or
>   is there some reason that you must use the tranceiver cable?

Yes, it can be plugged (at least in practice) directly.  We use lots
of MX-10 transceivers this way.

>5) Are thinnet segments supposed to be grounded somewhere?

Yes, one grounding.  Maybe it was Multiconnect which had also a jumper
for this, i.e. you have the possibility to ground the cable to the
grounding of the box (well ...? what about the quality of that?).

regards kari m.
From: nason@pa881a.inland.com
Newsgroups: comp.dcom.lans.ethernet
Subject: Re: Fiber speeddir
Date: 26 Aug 92 14:50:33 GMT
Organization: Inland Steel Company, East Chicago, IN

In article <1992Aug19.162023.16390@awdprime.austin.ibm.com>, jeffry@browncow.austin.ibm.com writes:
> 
> In article <1992Aug18.181507.14439@picker.com>, SYSNET@engvax.picker.com (Leonard A. Visconti) writes:
>> Does anyone know the speed of a signal through fiber? For example, through
>> thick wire ethernet cable the propagation speed is about 77% of the 
>> speed of light. We are using 62.5/125 multimode fiber at 850 nm. 
> 

In general, fiber cable has a velocity of propagation of .65 c, or 65%.  This
works out to 195 x 10^6 m/s.  or about 5 ns per meter.  This is the figure that
is used in the 802.3 standard for calculating delay times over fiber links. 
Due to the nature of the cable, you will not find too much deviation from .65c.
  

-- 
My opinions are my own and not those of my company.  
Free advice is worth its cost.  
--- John M. Nason - NA9U ---|--------------------------------------------|
Inland Steel Company        |  -- nason@pa621a.inland.com                |
Process Automation MS 2-464 |  -- Fax:   219-399-7856                    |
3210 Watling Street         |  -- Voice: 219-399-2450                    |
East Chicago IN 46312       |"Ya can't shoot em till they stop sparklin" |
----------------------------|--------------------------------------------|
From: pim@cti-software.nl (Pim Zandbergen)
Newsgroups: comp.dcom.lans.ethernet
Subject: Re: Null Modem on EtherNet
Date: 30 Aug 92 20:20:07 GMT
Organization: CTI Software BV, The Hague, The Netherlands

henry@zoo.toronto.edu (Henry Spencer) writes:

>In article <TR27PB1w164w@Control.Com> ics.jjmc@control.com writes:
>>>you can't just connect two
>>ethernet cards together with a "null modem" and get it to work. 
>>
>>Maybe you can, if you don't understand the problem. For the IEEE
>>Conference here this Spring, we hooked an AT and an XT together
>>with 10 feet of coax...

>He's talking about hooking AUI port to AUI port.  Not all Ethernet
>cards have the coax interface.

Black Box have a device that connects two machine through
their AUI ports.
-- 
Pim Zandbergen                      domain : pim@cti-software.nl
CTI Software BV                     uucp   : uunet!mcsun!sun4nl!ctisbv!pim
Laan Copes van Cattenburch 70       phone  : +31 70 3542302
2585 GD The Hague, The Netherlands  fax    : +31 70 3512837
Newsgroups: comp.dcom.lans.ethernet
From: pwb@newt.phys.unsw.edu.au (Paul W. Brooks esq.)
Subject: Re: Ethernet CRC/Alignment errors
Keywords: ethernet CRC errors
Organization: University of New South Wales
Date: Wed, 2 Sep 1992 08:42:27 GMT

In article <w8dnvyj.seifert@netcom.com>, seifert@netcom.com (Rich Seifert) writes:
> In article <1992Aug21.041709.3208@usage.csd.unsw.OZ.AU>, pwb@newt.phys.unsw.edu.au (Paul W. Brooks esq.) writes:
> > I have a piece of the campus ethernet that seems to have an excessive
> > number of CRC/Alignment errors. I have a Novell LANalyzer, and over an
> > hour or so reports no late collisions, no illegal long/short packets,
> > but a rate of CRC/Alignemtn errors sometimes up to 1 per 1000 packets.
> 
> Unfortunately, repeaters do not check the CRC of received packets,
> and simply pass them through. (By the time the CRC comes by, the packet
> is through anyway!). 

I was afraid of that. I don't have control of the entire campus ethernet
:-(. Another helpful reader suggested that they may be caused by IBM
RS/6000 machines, of which there are a few on campus, "dribbling" extra
bits at the end of some packets. Anybody else out there running RS/6000s
and NOT seeing CRC/Alignment errors? I'm guessing the errors are more
"Alignment" than CRC - they seem quite short, and the data insiode is
totally random.

> I would consider one CRC error per 1000 packets a SERIOUS problem.
> On a properly configured Ethernet, at 10% sustained load (24 hour
> period) and 256 byte (average) packets, in a 10^^-9 BER
> (the specified worst-case), there should
> be approximately 3.7 CRC errors every hour. That's about  one CRC error
> per one-half million packets!

Yes, but making our Computer Services Dept. see it that way is a little
more difficult.

The whole reason I was scanning the net was to try to resolve why our
NFS is quite slow. Quite often we get NFS errors, and data transfers
seem very slow - a few megabytes takes over 30 seconds, usually. This is
between two DECstation 5000s on the same piece of ethernet. Without
causing a flame war, does anybody else have problem with NFS between
DECstations?. Occasionally (several times a day) programs will not not
execute properly if they come from an NFS-mounted disk, failing with
"Illegal Instruction" errors, or swap errors, in which case the
corrupted program seems to be cached, so every attept to re-execute it
for the next few minutes meets with the same error message. sigh.

> -- 
> Rich Seifert                    Networks and Communications Consulting
> seifert@netcom.com              (408) 996-0922
>                                 (408) 996-2860 FAX
> "... specialists in Local Area Networks and Data Communications systems"

Thanks for the info.

Paul Brooks        |Internet: pwb@newt.phys.unsw.edu.au
Uni. of N.S.W.     |If you have trouble sleeping, try lying on the end of
Kensington NSW 2033|   your bed. With a little luck you'll drop off. 
AUSTRALIA          |                              - Mark Twain. 
Newsgroups: comp.dcom.lans.ethernet
From: gary@sci34hub.sci.com (Gary Heston)
Subject: Re: Laptop Ethernet adaptors for use with PC-NFS
Reply-To: gary@sci34hub.sci.com (Gary Heston)
Organization: SCI Systems, Inc., Huntsville, Al.
Distribution: usa
Date: Fri, 4 Sep 1992 15:28:28 GMT

In article <1992Aug31.191948.28978@pt.com> rkd@pt.com (Ray Downes) writes:
>I will likely have a need to interface a Laptop to an existing PC-NFS
>(revision 4.0a) "network", and was thinking of using one of the pocket
>adaptors (parallel port <-> 10baseT), via likely a NDIS driver. Anyone
>know of a source for these (hopefully that you seen work)? I've seen a
>Black box one (which seems about 2X "normal cost"), and one by Xircom.

Everything from Black Box seems to be 2x normal cost, except the items 
that are 4x.....

I just installed a LAN with 160 D-Link Pocket Lan Adapters, which is 
working fine (even though we're using them on desktop and tower chassis);
so far, we've only had one D-Link fail in 3 months of rough use.

Ours came via Accu-Tech Cable in Atlanta, Ga., 1-800-221-4767, and cost
considerably below list. Ask for Andy Curl.


-- 
Gary Heston    SCI Systems, Inc.  gary@sci34hub.sci.com   site admin
The Chairman of the Board and the CFO speak for SCI. I'm neither.
    The most dangerous person in the world is Jessica Fletcher.
        Everywhere she goes, people die.
Newsgroups: comp.dcom.lans.ethernet
From: barr@tramp.Colorado.EDU (BARR DOUG)
Subject: Mixing different twisted pair categories
Organization: University of Colorado, Boulder
Date: Wed, 2 Sep 1992 17:10:31 GMT

We have mostly category 3 twisted pair installed in our buildings.
We are considering installing category 5 in some runs, or as station
cables. Does anyone know of the effects of mixing the types
on one ethernet segment?

Newsgroups: comp.dcom.lans.ethernet
From: kunkee@ferranti.com (randy kunkee)
Subject: Re: multiport transceivers (was Re: what is SQE  (DUMB QUESTION!))
Organization: Unix/Xenix Support Group
Date: Mon, 31 Aug 1992 15:25:21 GMT

In article <44G6HJV@netmbx.netmbx.de> weis@netmbx.netmbx.de (Dietmar Weis) writes:
[ stuff deleted]
>SQE should be turned off for a transceiver connected to a *Thinwire* repeater.
>I don't know for a Standard Ethernet repeater.
>The reason is, that the SQE-Signal, which tests the Collision Detect
>functionality in the Ethernet Controller, will be transmitted via the
>Thinwire repeater to the whole Thinwire segment, which would **dramatically**
>slow down. On a 15-pin AUI-Cable to an Ethernet controller you have seperate
>Collision Detect lines, which you don't have on a Thinwire. So the SQE-Test
>sends it's test Collision Detect signals right onto the segment.

Someone correct me if I'm wrong, but having SQE enabled would never
send a false collision signal out onto the coaxial segment.  SQE is
only sent up the transceiver cable to the Ethernet controller, which
should be able to ignore it.

If your transceiver is actually connected to:
	1) A repeater
	2) A fanout box (which I think is a kind of repeater)
then what Deitmar says would be true:

>The attached stations think there are real collisions.
>
>Dietmar
>-- 
>weis@netmbx.netmbx.de       | Dietmar Weis         DONOP CONSULT GmbH
>Voice: +49 30 884 28 54-0   |                      Uhlandstrasse 179/180
>Fax:   +49 30 882 55 29     |                      D - 1000 Berlin 12
>                     I don't speak for my company!
-- 
Randy Kunkee
Ferranti International Controls Corporation
12808 W. Airport Blvd.  Sugar Land, TX 77478
UUCP: uupsi!ficc!kunkee       ph: (713) 274-5132
INTERNET: kunkee@ferranti.com
From: Jon Freivald <jaf@jaflrn.UUCP>
Newsgroups: comp.dcom.lans.ethernet
Subject: Re: Max Repeaters/multiport repeater wiring questions
Date: Fri, 04 Sep 92 00:49:59 EDT
Organization: The Wizzard's Cave, East Meadow, NY

Mehrtens_T@msm.cdx.mot.com writes:

> In article, Dave Hammond ashs:
> >how do I ground my thin-wire ethernet?
> >
> 
> I purchased some thin ethernet terminators with small tabs attached to them. 
> then solder some small solder-wick (braided wire) to the tab.  The cable is
> then connected to earth ground (In my case, all of our equipment racks are
> earth grounded (I tried moon grounded, but the cable kept spinning off)).  Th
> helps eliminate inductive noise on the cable at high transmission rates (burs
> over 35 - 50%) or in electronically noisy environments.
> 
> I know how you feel - most terminators do not provide any means of grounding,
> unless you sneak in solder-wick when a BNC cable is assembled (not an easy
> task).
> 
> I purchased the terminators from Anixter, Corp (major outlets in every major
> city).  
> 
> Cheers
> 
> Tom
> 
> 8-{)

If you get 3Com terminators, one of every pair comes with about 4' of
wire with an eye connector on the end.

=============================================================================
		   Jon Freivald ( jaflrn!jaf@uunet.UU.NET )
	 Nothing is impossible for the man who doesn't have to do it.
=============================================================================
Newsgroups: comp.dcom.lans.ethernet