[comp.protocols.appletalk] Broadcast IP on Apple LocalTalk

brad@cayman.COM (Brad Parker) (08/22/88)

From article <612@kinetics.UUCP>, by minshall@kinetics.UUCP (Greg Minshall):
> From article <63660@sun.uucp>, by pugs%whitsun@Sun.COM (Tom Lyon):
> There are a few points here.  First off, there is no relation between
> AppleTalk zones and IP subnetworks specified "anywhere".  The fact is
> that quite often there is such a relation, but no one can count on it.

I disagree. The MacIP implementations I know of do a lookup for the gateway
with the zone name "*".  This implies that the "domain" (if you will)
for the MacIP forwarding is the current zone.  The MacIP forwarding is
generally specified as an IP subnet or a subrange thereof. So, a relationship
excists between AppleTalk zones and IP subnet forwarding by the gateway.

I've taken this to further imply that an IP broadcast should be sent by
a gateway to all nets in the current zone, just and an NBP Bridge request
would be.

Certainly I haven't seen any of this on paper.  One could argue that it's
not part of any formal spec, but that the implementations seem to enforce the
relationship described above.

ps: I have a terrible cold and all of this might be jibberish; but at least
it's an interesting thought ;-)

-brad
-- 
"What will you do when you wake up one morning to find that God's made you
blind in a beautiful person's world and all those great recepies have let you
down, and you're twenty and a half and you're not getting age where you go look
for the boys 'says I love you lets get married and have kids." -Billy Bragg.