[comp.protocols.appletalk] lengthening Atalk network

PJORGENS@COLGATEU.BITNET (01/18/89)

Heinz Naef writes:

>After studying the AppleTalk brochure, it seems that even though there may
>be up to 32 devices attached to one network, BUT the total cable length
>shouldn't exceed 300 Meters (1000 feet). If you imagine a star-shaped
>wiring scheme in a large building, this diameter may be easily exhausted
>with 3 stations - even if they are in neighboring rooms!
>
>Is there a better solution which would allow to attach the Mac's to the IBM
>cabling while maintaining the full AppleTalk functionality transparently?
>(I. e. the user doesn't recognize that anything changed in the attachment?)

You should look into Farallon's PhoneNet StarController.  It is designed
to allow localTalk networks to run in a star configuration with longer cable
runs than Apple recommends.  It also comes with diagnostic SW to allow one
manager to control the network, isolate noisy nodes, etc. from any of the
attached Macs.

Several can be used together.
Peter Jorgensen
Microcomputer Specialist
Colgate University
BITNET     PJORGENSEN@COLGATEU
PHONE      (315) 824-1000 ext 742
APPLELINK  U0523
Colgate Disclaims

kent@lloyd.camex.uucp (Kent Borg) (01/20/89)

In article <Added.AXox94y00Ui34RaU8M@andrew.cmu.edu> PJORGENS@COLGATEU.BITNET writes:
>Heinz Naef writes:
>
>>After studying the AppleTalk brochure, it seems that even though there may
>>be up to 32 devices attached to one network, BUT the total cable length
>>shouldn't exceed 300 Meters (1000 feet). If you imagine a star-shaped
>>wiring scheme in a large building, this diameter may be easily exhausted
>>with 3 stations - even if they are in neighboring rooms!
...
>You should look into Farallon's PhoneNet StarController.  It is designed
>to allow localTalk networks to run in a star configuration with longer cable
>runs than Apple recommends.  It also comes with diagnostic SW to allow one
>manager to control the network, isolate noisy nodes, etc. from any of the
>attached Macs.

I have never used Faralon's star controller, but I am pretty sure that
each `arm' of the star can have many Macintoshs AppleTalked onto it.
Just do the regular daisy-chain routine.  You are not forced to use a
pure star wiring scheme, it can be a hybrid design.

Kent Borg
kent@lloyd.uucp
or
hscfvax!lloyd!kent

lynch@batcomputer.tn.cornell.edu (Tim Lynch) (01/21/89)

>
> I have never used Faralon's star controller, but I am pretty sure that
> each `arm' of the star can have many Macintoshs AppleTalked onto it.
> Just do the regular daisy-chain routine.  You are not forced to use a
> pure star wiring scheme, it can be a hybrid design.
> 

True, but be careful.  Stick with the guidelines as presented in the
Farallon literature.  Each arm of the Star Controller is seen as an
appletalk net, though you will no doubt run into problems with
congestion long before you come up against the physical limit on
number of machines.  We have.

The wiring must not be pure star, but, again, read Farallon's doc's.
For example, one run of our star controller, located at one end of
the building, goes to our administrative wing at the other end.  There
the twisted pair daisy-chains to about 8 Mac's and printers _and_
continues up a floor to several more Macs.  In addition to this leg,
we've got another leg running into an adjacent room with two mac's.
Note that from one of the Mac's in the admin wing, we simply daisy
chain via the PhoneNet blocks to some other macs. We've done this
at several locations throughout the net and haven't had any problems
with it.  Well, let me rephrase that, we can't attribute any problems
we've had to this configuration.  My little diagram shows just one
of the twelve legs of the star controller:

                             (short run to room adjacent to Star C)
Star Controller ] ----------------------------------------------- 
                   |                                     |      |
                   |                                    Mac    Mac
                   |
                   |---- LW 
                   |
                   |---- Mac
(admin wing)       |  
                   |   ( not all machines shown)
                   |
                   |---- Mac ---- Mac ---- LW
                   |
                   | 
                   |
                   |
                   |      (second floor)
                   ------------------------
                          |               |
                          |               |
                         Mac             Mac


We've got a good size net (~40 Macs, half dozen laserwriters, half
dozen PC's, a star controller, bridges, and a Kinetic box) running
Appleshare.  We've run everything over twisted pair originally strung
thoughtout the department buildings to support async terminals tied
to the departmental machine.  In tracing any one pair of wires from the
Star Controller to a Mac "flock" or "gaggle", say the Admin wing, you
would find that the wires originally went through "punch down" blocks.
These are the quick-connect things the phone company used in the old
Centrex systems.  I say all this because if you intend to make use of
pre-existing wiring -- DON'T GO THROUGH PUNCH DOWN BLOCKS !!!  We've
had to go through our entire net, pulling wires free of the punch-down
blocks and soldering them directly.  Really cleaned things up though.

edwards@bgsuvax.UUCP (Ken Jenkins) (01/23/89)

In article <303@lloyd.camex.uucp>, kent@lloyd.camex.uucp (Kent Borg) writes:
> In article <Added.AXox94y00Ui34RaU8M@andrew.cmu.edu> PJORGENS@COLGATEU.BITNET writes:
> >Heinz Naef writes:
> >
> >>After studying the AppleTalk brochure, it seems that even though there may
> >>be up to 32 devices attached to one network, BUT the total cable length
> >>shouldn't exceed 300 Meters (1000 feet). If you imagine a star-shaped
> >>wiring scheme in a large building, this diameter may be easily exhausted
> >>with 3 stations - even if they are in neighboring rooms!
> ...
> >You should look into Farallon's PhoneNet StarController.  It is designed
> >to allow localTalk networks to run in a star configuration with longer cable
> >runs than Apple recommends.  It also comes with diagnostic SW to allow one
> >manager to control the network, isolate noisy nodes, etc. from any of the
> >attached Macs.
> 
> I have never used Faralon's star controller, but I am pretty sure that
> each `arm' of the star can have many Macintoshs AppleTalked onto it.
> Just do the regular daisy-chain routine.  You are not forced to use a
> pure star wiring scheme, it can be a hybrid design.

In addition, if adaptor cables are purchased (also available from 
Farallon) to convert the mini-Din 3 from a Apple node transformer
to the RJ-11 plug used to connect to the RJ faceplate, and if the
first node on the daisy chain is a "honest-to-goodness" Farallon
box, you can continue to use the Apple boxes down the line. Also
note that the length of each daisy-chain off the star controller
is dependant on the wire gauge used for the twisted pair and the
data transfer rate (FalshTalk, DynaTalk, etc. shorter).

> Kent Borg


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