F. Alfredo Rego wrote:
> Bruce Toback <[log in to unmask]> wrote:
> >... AppleTalk
> >was designed for networks of a few thousand nodes. Up to about a
> >thousand, with a dozen or so zones (subnets), it's self-configuring -
> >even the routers are self-configuring...

> Now I see why we have never had any difficulty whatsoever with our
> AppleTalk/EtherTalk networks at Adager.  We have a reasonably long way
> to go before we hit the 24-bit limit :-)

You're hitting pretty close to home here and I must respectfully
disagree.  Appletalk version 1 has essentially an 8-bit address space,
while version 2 allows a "cable range" of consecutive 16-bit network
numbers.  It can indeed be self-configuring within a narrow scope of a
single network, but it stops there.

When we have a prolonged power outage, it can take a day or more to get
Appletalk working again.  Typical Appletalk devices come up and listen
for their network (cable-range) number.  If they don't hear one, they
make one up.  Then they make up a node number and check for a conflict.
The consequence of this is that the first AT device that powers up and
sets its network parameters dictates the network number that will be
used, and subsequent devices will follow suit.  If you happen to have a
real router on the subnet, or a Shiva Ethergate, or a GatorBox, or other
Localtalk to Ethertalk gateway on the net, they won't be happy,
particularly if they are configured as seed routers.  The end result is
that you must power off every Appletalk device on the segment and reset
the network/host numbers on your seed router and start all over again.

Most of the time it works great, and I can appreciate the logic behind
it for typical applications.  However, it is the most difficult to debug
when things go wrong, speaking from experience.  We route AT across 12
subnets.  I dread power outages :-(

> >TCP/IP isn't self-configuring even at two nodes,

One word (well acronym) ... DHCP

> Alfredo (I'm glad I never had to become a networking expert to
> "manage" all of Adager's Intranet/Internet stuff, which runs on
> Macs...  Life is too short and full of other wonderful things to do!)

Try it with hundreds of nodes sometime :-)

Jeff Kell <[log in to unmask]>