David Conrad wrote:
One of the advantages I see in LISP(-like) solutions is that it allows multi-homing without having to do BGP...
By having a lot larger table than BGP. http://datatracker.ietf.org/doc/draft-ietf-lisp-architecture/?include_text=1 It should be noted that the caching spoken of here is likely not classic caching, where there is a fixed/limited size cache, and entries have to be discarded to make room for newly needed entries. The economics of memory being what they are, there is no reason to discard mappings once they have been loaded (although of course implementations are free to chose to do so, if they wish to). Worse, the table is updated so frequently. http://datatracker.ietf.org/doc/draft-ietf-lisp-introduction/?include_text=1 A node may have more than one RLOC, or its RLOC may change over time (e.g. if the node is mobile), but it keeps the same EID. Assuming that there are 4G mobile devices in the world, the mapping table has more than 4G entries each updated every minute or second. The problem of LISP is that it breaks the end to end principle to introduce intelligent intermediate entities of ITR and ETR. Mobility can best be handled end to end by end systems of MN, HA and, optionally, CN. Masataka Ohta PS Considering that the Internet is connectionless because all the routers have routing tables covering all the IP addresses in realtime, LISP won't be operational unless most of routers in DFZ have full mapping table in realtime.