[ih] Source routing, IEN 80, and IEN 95

[Miles Fidelman]

At 0:40 +0200 2010/08/06, Matthias Bärwolff wrote:
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>>> Hi everyone out there. I am wondering (mainly just out of curiosity)
>>> about the implementation and usage record of source routing in the 
>>> early
>>> Internet. The IPv4 spec (starting with IEN 80) came to include it
>>> eventually, but my impression is that while people *thought* it 
>>> would be
>>> important, in reality no one cared too much and it wasn't used much.
>>>
>>> My question: have people actually been using it for purposes other than
>>> spoofing attacks? What about routing debugging? And, load balancing?
Your question sparked my curiousity, so I did a little digging.

As I recall, from a long time back, there was a collection of work on 
routing that involved "route servers" and source routing - instead of 
relying on routers to maintain routing information, a protocol stack 
would request a route from a route server, and then use source routing 
to send packets along that route.

More recently, it looks like source routing is being used in some of the 
experimental routing models applied in MANETs (mobile ad hoc networks) - 
for example DSR (Dynamic Source Routing), 
http://tools.ietf.org/html/rfc4728 - the basic model is that nodes do 
"route discovery," to find paths to other nodes, and then use source 
routing to push packets along those routes.  There's a pretty good list 
of various MANET protocols on Wikipedia, at 
http://en.wikipedia.org/wiki/Ad_hoc_routing_protocol_list

I haven't dug further, but I expect that source routing becomes a lot 
more secure if you add some cryptographic authentication into the mix.

Miles Fidelman


-- 
In theory, there is no difference between theory and practice.
In<fnord>  practice, there is.   .... Yogi Berra