On 07/02/11 14:25, Jamie Bowden wrote:
It would help if we weren't shipping the routing equivalent of the pre
DNS /etc/hosts all over the network (it's automated, but it's still the
equivalent). There has to be a better way to handle routing information
than what's currently being done. The old voice telephony guys built a
system that built SVCs on the fly from any phone in the world to any
other phone in the world; it (normally) took less than a second for it
to do it between any pair of phones under the NANPA, and only slightly
longer for international outside the US and Canada. There have to be
things to be learned from there.
Jamie
They did indeed, but they did it by centrally precomputing and then
downloading centrally-built routing tables to each exchange, with added
statically-configured routing between telco provider domains, and then
doing step-by-step call setup, with added load balancing and crankback
on the most-favoured links in the static routing table at each stage.
All this works fine in a fairly static environment where there are only
a few, well-known, and fairly trustworthy officially-endorsed entities
involved within each country, and topology changes could be centrally
planned.
BGP is a hack, but it's a hack that works. I'm not sure how PSTN-style
routing could have coped with the explosive growth of the Internet, with
its very large number or routing participants with no central planning
or central authority to establish trust, and an endlessly-churning
routing topology.
Still, every good old idea is eventually reinvented, so it may have its
time again one day.
-- Neil
