"Howard C. Berkowitz" wrote:
>
> The direct ancestor of IS-IS is DECnet Phase IV routing, principally
> designed by Radia Perlman. DEC contributed its work to ISO, and
> IS-IS was initially developed as a pure OSI routing protocol (i.e.,
> for CLNP). IS-IS became the native IGP for DECnet Phase V, which was
> OSI (protocol, not just model) at its lower layers. This was at a
> time when many European governments, and their PTT's that dominated
> international standards, were very anti-IP. I am _not_ making it up
> when I quote, from my experience in OSI standards committee, European
> PTT people saying they would not accept a protocol suite "designed by
> the bomb-crazed American military."
>
Back in 90-91, Ross Callon of DEC was leading the technical charge on
IS-IS standardization. DEC was arguably the premier networking vendor
at the time, and had considerable clout in the committee space.
And let's not forget that John Moy was at DEC before he went to Proteon,
where he developed OSPF, borrowing a number of the same terms and
mechanisms (link "cost", hellos with neighbors, etc.)
> In 1986-1988, the US government issued the Government OSI Profile
> (GOSIP), which mandated OSI protocols for future government use.
> Integrated IS-IS, in part, was intended as an interim protocol to use
> while people migrated from proprietary and IP protocols to OSI.
>
The USG was forced to grant waivers left and right, because most vendors
did not have robust OSI stacks to offer. Everyone wanted others to go
first, to incur the big R&D expense. Those vendors that did so wanted
to recoup their investment (e.g, DEC). But they found reluctant buyers;
the classical critical mass problem. While vendors talked a good line,
customers watched and waited, and found the slim offerings to be lacking.
In the mean time, IP did an end run. One of the important reasons was
that standards development followed the IETF model -- draft, RFC, test
interoperability between at least two independently constructed versions,
modify as necessary; then declare as standard. The ISO approach at the
time was to have equal political representation from many countries,
over-specify tons of complexity, declare it a standard; then go build it.
Later GOSIP issued a relaxed version of the mandate, saying that OSI was
still preferred, but that TCP/IP could be used where OSI was not possible or
practical. Finally they just threw in the towel and stopped pretending.
Large U.S. corporations were already on board the TCP/IP bandwagon.
Europe lagged but eventually succumbed, once their corporations followed
the universities, and ignored the wishes of the PTTs.
> Of course, market forces drove the world to the IP protocol suite. I
> hate to say IP won the war over OSI; it's more that the two
> intermarried. The good protocol things in OSI have wound up in IP,
> and the bad things are mostly forgotten.
>
I thoroughly enjoyed attending Interop (back when it was mostly technical)
and hearing Marshall Rose speak. Admittedly an IP bigot, he proclaimed
"OSI is the dream, and TCP/IP is living it!" Quite accurate when you
think about it. The laudable goal of OSI was to create a layered model
to which hardware and software vendors would design their wares. Customers
would benefit from more choices (competition) at each layer, and product
designers would be able to more rapidly introduce innovations within a
layer without impacting other layers. Networking would become ubiquitous
and cheap. Gee, kinda sounds like the recent history of IP (and Ethernet). :-)
This standardization "craze" grew from the disgust of customers tired of
having to buy their cables from the same company that sold them the O/S
and the applications, and the big iron, and so on.
BTW, Marshall rose was a prolific programmer who knitted such combinations
as CMOT (CMIP over TCP/IP) and other hybrids. He also liked to poke fun
at how fragile and unfriendly X.400 email transports were in those days.
(I know -- I built an X.400 gateway between VAXmail, Data General X.400,
IBM PROFS, SoftSwitch, and public X.400 carriers. Since DEC was pushing it,
we used it to communicate with our DEC salespeople. But we quickly found
that we should send all messages via X.400 and SMTP, since the latter always
worked, or at least gave a NDN message reply.
Marshall would pose the question to an audience: if an SMTP user and an
X.400 user meet at a conference and exchange cards with email addresses,
how to they communicate? A: the SMTP user sends a message to the X.400
user, whereupon the X.400 user saves that sender address for future replies.
Corollary: what happens if two X.400 users meet at a conference and exchange
cards and addresses? A: They pick up the telephone... :-) Folks, if
you've never typed in one of these obscenely long addresses, you'll not
appreciate it.
Exit nostalgic mode,
Marty Adkins Email: [EMAIL PROTECTED]
Mentor Technologies Phone: 410-280-8840 x3006
275 West Street, Plaza 70 WWW: http://www.mentortech.com
Annapolis, MD 21401 Cisco CCIE #1289
_________________________________
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
