On Mon, Apr 11, 2011 at 9:19 AM, Jeff Wheeler <j...@inconcepts.biz> wrote: > On Mon, Apr 11, 2011 at 11:26 AM, Owen DeLong <o...@delong.com> wrote: >> I'd agree with you if it weren't for the fact I keep thinking I just about >> understand LISP and then get told >> that my understanding is incorrect (repeatedly). > > I agree it is not simple. > > At a conceptual level, we can think of existing multi-homing practices > as falling into one of three broad categories: > 1) more state in DFZ -- end-site injects a route into BGP > > 2) triangular routing -- tunnel/circuits/etc to one or more upstream > routers while not injecting anything to DFZ > > 3) added work/complexity on end-host -- SCTP and friends > > LISP is a compromise of all these things, except #3 happens on a > router which does tunneling, not the end-host. Whether you think it's > "the best of both [three?] worlds," or the worst of them, is up to > you. > > I personally believe LISP is a horrible idea that will have trouble
Yep. > scaling up, because a large table of LISP mappings is not any easier > to store in FIB than a larger DFZ. The "solution" the LISP folks > think works for this is a side-chain mapping service which the router > can query to setup encapsulation next-hops on-demand, which means if > your FIB isn't big enough to hold every mapping entry, you are > essentially doing flow-based routing, but with "flows" defined as > being toward a remotely-defined end-site rather than toward an > individual IP address (so not quite as bad as "flow-based routing" of > the past, but still bad.) > > Maybe I also don't understand LISP and need to RTFM more, but my > current understanding is that it is a dead-end technology without the > ability to dramatically scale up the number of multi-homed end-sites > in a cheaper manner than what is done today with BGP. > > I think we would be better off with more work on things like SCTP. > +1 SCTP and IPv6, then ILNP. > -- > Jeff S Wheeler <j...@inconcepts.biz> > Sr Network Operator / Innovative Network Concepts > >
