mazu@terre.DMI.USherb.CA (Marc Mazuhelli) (11/01/90)
Hi there everyone,
I have a few questions I would like some of you experienced network
managers to answer. This message is a bit long; I wanted to warn you!
i) the maximum number of nodes on a LocalTalk/Phonenet cable segment is
supposed to be 31 (or is it 32?). At first I thought that it had to do
with the length of the whole segment, and that if all the machines are
all pretty near, we could put more machines. So I tried to put 33 Mac
Pluses and ont SE/30 (an Appleshare server) with 5 AppleTalk
ImageWriters all in the same segment (using LocalTalk cabling which we
already had; if not, I would have gone with Phonenet or, even better, a
star controller). Everything seems to work; what is it that is so bad
about having 39 nodes on a same segment of cable? (this is a lab for
undergraduate students, and all the machines are in the same room so
there can't be any problems with distace).
If the answer to i) is that it *is* wrong to have so many devices,
I see a few ways to split the net in two:
a) a NetBridge or similar device;
b) Liaison or Apple's Internet Router on the SE/30 using
both serial ports;
c) a Shiva EtherGate *or* Compatible Systems EtherRoute
which both have *two* Localtalk ports.
ii) Since I also want to hook that net to our Ethernet backbone (to access
our Sun servers using TCP/IP), I have eliminated a) because I'm not sure
that Netbridges allow TCP/IP traffic to go through. Is that right?
iii) We already have Liaison, but it doesn't handle TCP/IP neither,
right? (unless that has changed with the new version 3.0 for which I
haven't received the upgrade notice yet...). Apple's router doesn't do
TCP/IP either.
iv) Regarding the Ethergate, I think that it supports TCP/IP, but not
DDP/IP encapsulation necessary to make things like CAP and AUFS work (at
least it didn't a few months ago when I asked). Has that changed?
v) I called Compatible Systems recently and they told me that they are
working on TCP/IP for their Etheroute, and that it *will* support
DDP/IP, CAP and AUFS when it's released sometime in december (I think).
Does anyone have any experience with the Etheroute?
vi) To my knowledge, there's only one *software* bridge/router that
supports TCP/IP completely (including DDP/IP); I'm not sure of the name,
but I think it's the same software that runs in NRC's Multigate (not
Webster's). Would it work on an SE/30 that's used as an AppleShare
server? Could it support a LocalTalk segment on each of the serial
ports? Are there any other *software* routers that work with two
Localtalk nets, support TCP/IP and DDP/IP and work in the backgroung
on an Appleshare server? Or should I stop looking for a software
solution and go with a *hardware* router?
vii) One other solution would be to put a star controller *and* one of the
other gateways that have only one Appletalk port: a FastPath or Gatorbox.
We already have one GatorBox to hook up another Localtalk segment (our
"staff" network) to our Ethernet backbone. I like it, but one of the
problems is that I am in Canada and I don't have access to educational
prices as Cayman insists I go through their Canadian distributor,
McKensie Brown. On the other hand, Shiva and Compatible Systems will
give us educational discounts; that makes the GatorBox more expensive
that most of the other solutions.
I would like to stay away from the Fastpath because, from all I have
read here and elsewhere, it seems to be a hassle to get working and the
support doesn't seem ideal. I also don't like the fact that you have to
get hardware upgrades all the time (sometimes it's just the ROMs, but
there have been 4 versions of the box itself!). Even if we chose the
Fastpath (with educ. discount), if I have to add the price of a star
controller, that would become much more expensive than, say,
just an Etheroute (for which we also get educ. discounts!)
I know about Webster's Multigate which has 4 localTalk ports
(we don't really need that many) and it's a bit too expensive;
it also doesn't support zone or laserwriter security (we don't
want our ungergraduate students to use the LaserWriters on the
"staff" network).
******* End of the questions! ********
As ou can see, I have a lot of questions regarding the expansion of our
network (in fact, this turned out to be longer that I thought it
would be!). If some of you are willing to help me a bit with one or a few
of these questions, I would be very grateful.
You could answer through regular mail at the address below if you want,
and I will summarize if I get enough interesting answers.
Thank you very much!!
--
{ Marc Mazuhelli | professeur }
{ internet: mazu@dmi.USherb.CA | Departement de math-info. }
{ <this space intentionaly ... | Universite de Sherbrooke }
{ ... left blank> | Sherbrooke, Quebec, Canada }