🚀 go-pugleaf

In article <1992Sep1.090218.14742@spider.co.uk>, brianw@spider.co.uk (Brian Wyld) writes:
>From: brianw@spider.co.uk (Brian Wyld)
>Newsgroups: comp.dcom.lans.misc
>Subject: Token Ring: do all stations support LLC XID?
>Date: 1 Sep 92 09:02:18 GMT
>
>Hi,
>
>This is probably a question for comp.dcom.lans.token-ring, but as it doesn't
>exist (as far as I'm aware).....

	There seems to be insufficent interest to form or sustain such a 
group at last attempt.

>The question is, do all stations on Token Ring networks running support LLC,
>and specifically LLC XID request/responses? I know that the TI TR chip
>certainly seems to assume you run LLC over the MAC layer, but is this
>universally true?

	All 802 stations must be running LLC as it is part of the standard
and XID and TEST response servers are required LLC functions.

	Aside from that, practically speaking, TI licences the microcode
for the LLC layer seperately from the MAC layer.  So it's quite possible
to have an adapter without LLC functions.  However, it's not a very
viable product in the TR market, since all IBM protocols use LLC Type 2.

>My experience is only with TCP/IP, where its LLC/SNAP/IP type stack, but
>what about IPX, SNA, Vines, etc etc?

	To the best of my knowledge, only IBM protocols (SNA, NETBEUI)
use LLC Type 2.  All other protocols mentioned use connectionless data link
service (LLC Type 1).

>The reason for the question is to get the right echo frame to put source
>routing explorers onto so that as many protocol stacks as possible will
>answer.

	There is no real right answer to this.  XID's to the Null SAP
is probably the best.  You should look into a document under work in
802.5 called the RDE (Route Determination Entity 802.5P) that is attempting
to solve this problem.

	Dave Mitton
	Token Ring Program
	Digital Equipment Corp.