Geographic routing hack

Martin Cooper mjc at
Mon Aug 2 20:53:45 UTC 1999

Some weeks ago I noticed that
( appears to reach web servers
located in physically different places broadly
dependent on where you see it from.

I presume this is done by advertising the same
prefix from border routers which are in seperate
IGP domains or something (confederations maybe?),
but I wonder what people's views on the concept are,
since it could potentially be quite confusing in
certain circumstances (e.g. debugging routing
problems) ?

Superficially it seems like a 'cool hack' for
geographic content-distribution (which is what
Digital Island do), but up until now I've always
seen this sort of thing done by exploiting NS
record sorting order properties with the kludge
of different A records in the various zonefiles,
and I wondered if doing it with routing policy in
this way is strictly RFC compliant (or for that
matter if anyone cares if it isn't) ?


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