[UUG/MLUG] good network info

["Roberts, Michael J. (IATS)" <EMAIL:PROTECTED>]

Go to your favorite search engine and type 'csma/cd' or 'csmacd'.  I won't
tell you all what the ancronym means.  You'll find probably more information
on networking that you could possibly want.  Have fun. (:

-mike

-----Original Message-----
From: McNutt, Justin M. [mailto:EMAIL:PROTECTED] 
Sent: Monday, November 29, 1999 9:21 AM
To: EMAIL:PROTECTED
Subject: RE: [UUG/MLUG] Various networking questions:


<grin>  Plagiarize away!  Knowledge like this was meant to be shared anyway.
Hoarding it just holds people back.  <shrug>  Mention me on the page,
though, if you feel like having a "For clarification or other questions"
link (and you don't point it to yourself) <grin>.  But I don't mind doing
it, and I'd be honored to be quoted.

Thanks!

--J

> -----Original Message-----
> From: Buford, Rick [mailto:EMAIL:PROTECTED]
> Sent: Monday, November 29, 1999 8:23 AM
> To: EMAIL:PROTECTED
> Subject: RE: [UUG/MLUG] Various networking questions:
> 
> 
> As many times in the recent past as this question has been 
> asked, I was
> thinking about trying to do a real simple page with some 
> decent diagrams so
> we could simply refer people to it rather than explaining it 
> each time. Do
> you mind if I plagarize you so I don't have to re-write it again?
> 
> Rick Buford
> Chief Clerk
> Medical Records - Transcription
> DC042.06 / 884-7452
> "A bus station is where a bus stops. A train station is where a train
> stops. On my desk I have a workstation...."
> 
> 
>    |-----Original Message-----
>    |From: McNutt, Justin M. [mailto:EMAIL:PROTECTED]
>    |Sent: Sunday, November 28, 1999 2:00 PM
>    |To: EMAIL:PROTECTED
>    |Subject: [UUG/MLUG] Various networking questions:
>    |
>    |
>    |There have been various networking/cabling questions on 
>    |here lately.  Here
>    |are some of the answers, answered ad nauseum <grin>:
>    |
>    |1)  There are several kinds of Ethernet over CAT5.  One is 
>    |10BASE-T, which
>    |uses pairs 1-2, and 3-6.  Another is 100BASE-TX which is 
>    |100Mb and uses the
>    |same four wires as 10BASE-T.  Another is 100BASE-T4 which 
>    |uses all four
>    |pairs in CAT5, and the last is 100BASE-T2, which uses the 
>    |same four wires as
>    |10BASE-T, but can be used with CAT3 cabling (lower quality).
>    |
>    |Only 10BASE-T, 100BASE-TX, and 100BASE-T4 can use autonegotiation.
>    |100BASE-T2 has no standard for that yet.  10BASE-T and 
>    |100BASE-TX are the
>    |most common and use only four of the eight wires available 
>    |in standard CAT5.
>    |
>    |2)  If you are going to wire your house, use plenum cable 
>    |(has to do with
>    |the coating - not the shielding - and fire regulations), 
>    |and keep it well
>    |away from power lines.  The three feet mentioned before for 
>    |unshielded
>    |cabling sounds about right.
>    |
>    |3)  You can use any single pair of CAT5 for a phone line, 
>    |for up to three
>    |lines in a jack (RJ11 jacks have only six leads).  This is 
>    |a good idea since
>    |the twisting in CAT5 gives you better signal quality for 
>    |your local loop
>    |(the wiring in your house).
>    |
>    |4)  You can *try* running 10BASE-T or 100BASE-TX over four 
>    |of the wires in a
>    |CAT5 cable, and running phones over one or both of the 
>    |other pairs.  As long
>    |as the jacks are a bit apart, I can't see that there would 
>    |be much of a
>    |problem, since they use such vastly different frequencies.  
>    |Remember that
>    |even a 28.8kbps modem is actually running at 2400 *baud*, 
>    |but uses phase
>    |modulation to transmit many bits per baud.  So you have the 
>    |modem at 2400Hz
>    |and the network at 125MHz (100Mb Ethernet).  The signal 
>    |filters in each set
>    |of devices should keep out the noise (if any) from the other.
>    |
>    |Of course, that's theory.  It *should* work, but you'll 
>    |have to try it.
>    |
>    |5)  All you have to do to hook two Ethernet computers 
>    |together is make (or
>    |buy) a crossover cable.  They can be purchased 
>    |commercially, you just have
>    |to ask for them sometimes.
>    |
>    |Here's the instructions for making your own Ethernet 
>    |crossover cable (this
>    |is long):
>    |
>    |You need a CAT5 patch cord, a crimper with an RJ45 die, and 
>    |the appropriate
>    |RJ45 tips.  Pay attention to the type of cable you have 
>    |because there are
>    |different tips for solid cable and stranded cable (is the 
>    |copper wire a
>    |single solid wire or a lot of little wires?).  Make sure 
>    |you have the right
>    |die for the tips you're using.  For computer-to-computer, 
>    |stranded cable is
>    |recommended.
>    |
>    |Those parts are available from catalogs, and probably from 
>    |Insight.com if
>    |you poke around a bit.
>    |
>    |For 10BASE-T or 100BASE-TX, look at one end of the cable.  
>    |Write down the
>    |colors of the wires *in order* as you see them.  Here's 
> an example:
>    |
>    |Pin 1:  Orange
>    |PIn 2:  White-Orange
>    |Pin 3:  Blue
>    |Pin 4:  White-Green
>    |Pin 5:  Green
>    |Pin 6:  White-Blue
>    |Pin 7:  Brown
>    |Pin 8:  White-Brown
>    |
>    |Note that 3 and 6 are a pair and 4 and 5 are a pair.  They 
>    |don't just go
>    |1-2, 3-4, 5-6...
>    |
>    |Anyway, chop off the connector at the other end.  Then, 
>    |using the example
>    |colors above (you'll have to modify these instructions for 
>    |your cables), you
>    |would insert the wires at the other end into one of the 
>    |RJ45 tips in this
>    |order:
>    |
>    |Pin 1:  Blue
>    |Pin 2:  White-Blue
>    |Pin 3:  Orange
>    |Pin 4:  White-Green
>    |Pin 5:  Green
>    |Pin 6:  White Orange
>    |Pin 7:  Brown
>    |Pin 8:  White-Brown
>    |
>    |Note that *pair* 1-2 gets swapped with *pair* 3-6.  Now the 
>    |transmit pair on
>    |one side goes to the receive pair on the other side, and 
>    |vice versa.  This
>    |is because usually you have a concentrator (or switch) do 
>    |this for you, but
>    |since you're going to plug directly into the interface at 
>    |the other side,
>    |you have to swap the wires yourself.
>    |
>    |Anyway, make sure you untwist the wires as little as 
>    |possible getting them
>    |into the RJ45 tip, and crimp it with the crimper.  Then 
> try it out!
>    |
>    |To make a Token Ring crossover, it's pretty much the same 
>    |thing, but you
>    |have to crossover pairs 3-6 and 4-5 instead.  I don't know 
>    |about 100BASE-T4,
>    |and I don't think you *can* crossover 1000BASE-T (Gb).  
>    |100BASE-2 should be
>    |the same as 100BASE-TX.  I have the specs on all of those 
>    |somewhere if
>    |somebody's really interested.  <grin>.
>    |
>    |Clear as mud?  Hope some of that helps!
>    |
>    |--J
>    |
>