IPv4 address length technical design
pvinci at VinciConsulting.com
Sun Oct 7 22:20:28 UTC 2012
> Ok, then let's take a step back, perhaps not permanently, and say DNS
> resolution is only really useful for routers with more than just a
> single default external route.
> So DNS could be reduced to an inter-router only protocol, similar to
> BGP in some sense.
LISP DDT uses a lookup to determine EID location.
We operate one of the DDT roots, and yes the difference is that LISP uses an on-demand pull mechanism, where the route is looked up and then cached until it ages out from inactivity. BGP pushes every route to peers and everyone running BGP pays a hardware tax for carrying each and every route. (See Bill Herrin's work at http://bill.herrin.us/network/bgpcost.html) DDT provides a scalable, distributed database similar to DNS for looking up prefixes in LISP mapping servers.
More information about the NANOG