[ih] The story of BGP?

[Noel Chiappa]

    > From: Tony Li <tony.li at tony.li

    >> I'm not sure where 1994 comes from (that's the date on BGP-4, is that
    >> it?), but it's wrong.

    > The transition was more in the '91-'93 window. The urgency to publish
    > the RFC was far lower tha n the need to have working code and a working
    > network.

Are you talking about the transition to BGP-4, or the transition to BGP? My
comment was about the transition to use of BGP, which my memory (perhaps
falsely) indicated had gotten a fair amount of use quite quickly.

However, it sounds like I may have relied too heavily on the RFC dates, and
that BGP came along much more slowly than that?


    >> Was the shutdown of the ARPAnet a big factor?

    > Absolutely.

I'm trying to see how this can be?

As far I as can work out, the need to move to something better than EGP was
driven by the growth of the network (growth both in terms of number of total
destinations, as well as the richness of the inter-connections), and that
growth was not driven in any way by the ARPANET (or its demise).

Rather, the growth was driven by the deployment of LAN technologies (which
provide very high speeds), and the increasing numbers of smaller machines
(initially mini-computers, and then personal machines), which provided a need
for LANs (and hence for the growth in the number of destinations). There was,
slightly later on, a parallel evolution in transmission technology (i.e.
fiber), which drove inter-connection richness (and higher long-distance
speeds).

(Simply speeding up the ARPANET, to avoid the growth of the alternate
backbones, was not an option. The ARPANET's whole architecture was just not
suitable for high speeds. In particular, the 8-outstanding-packet limit would
have been a killer - particularly as all IP traffic shared one 'link'.)

As far as I can see, the ARPANET was only important as the first
long-distance backbone, to tie together all the disparate sites - and thus
the need for a protocol family which could handle such a large network
(unlike other early protocol families like PUP and CHAOS, which were clearly
single-site oriented, although they eventually were used in slightly larger
contexts).

As best I can recall, when the ARPANET was finally turned off (after a long
process of shrinkage) it was pretty much a non-event, as was the process of
shrinkage - people just signed up with regionals - which had originally been
set up to serve those people who couldn't get on the ARPANET.

    > The creation of the NSFnet regionals added thousands of prefixes to the
    > routing tables very quickly, causing EGP updates to grow rapidly.
    > ...
    > This pain became obvious to everyone, and was coupled with the
    > significant pain of route filtering that had to be used to prevent the
    > looping that has already been discussed.

All true, but this had nothing to do with the existence, or non-existence, of
the ARPANET (see above).

	Noel