On 11, Apr, 2011, at 15:37 , Owen DeLong wrote: > > On Apr 11, 2011, at 6:30 AM, Luigi Iannone wrote: > >> >> On 11, Apr, 2011, at 15:17 , Owen DeLong wrote: >> >> [snip] >>>>> >>>>> Doing IPv4 LISP on any kind of scale requires significant additional >>>>> prefixes which at this time doesn't seem so practical to me. >>>> >>>> This is not accurate IMO. To inject prefixes in the BGP is needed only to >>>> make non-LISP sites talk to LISP sites. Even there you can aggressively >>>> aggregate, as explained in draft-ietf-lisp-interworking. >>>> >>>> As long as the LISP deployment progress you can even withdraw some >>>> prefixes from the BGP infrastructure and advertise only a larger aggregate >>>> in order for legacy site to reach the new LISP site. >>>> >>>> Luigi >>>> >>> Who said anything about BGP? I was talking about the amount of additional >>> IP space needed vs. the >>> amount of IPv4 free space remaining. >>> >> >> Sorry. I misunderstood. >> >> But can you explain better? Why should LISP require more IP space than >> normal IPv4 deployment? >> >> If you are a new site, you ask for an IP block. This is independent from >> whether or not you will use LISP. >> > Sure, but, if you also need locators, don't you need additional IP space to > use for locators?
No, those are the IP address that you provider gives to your border router. > >> If you are an existing site and you want to switch to LISP why you need more >> space? you can re-use what you have? >> > Perhaps I misunderstand LISP, but, I though you needed space to use for > locators and space > to use for IDs if you are an independently routed multi-homed site. Not exactly. You do not need more space. You re-use what you have. > > If you are not an independently routed multi-homed site, then, don't you need > a set of host IDs > to go with each of your upstream locators? > > As I understand LISP, it's basically a dynamic tunneling system where you > have two discrete, > but non-overlapping address spaces, one inside the tunnels and one outside. > > If that's the case, then, I believe it leads to at least some amount of > duplicate consumption of > IP numbers. > No true. I ask for a PI block that I will use as EID-Prefix, then the locators are part of the address space of my providers. There is no duplication. >> Or I missed the point again? >> > Or perhaps the complexity of LISP in the details still confuses me, despite > people's insistence > that it is not complex. > IMHO it is very simple. As any new technology there is just a learning curve to follow, but for LISP it is not steep ;-) Luigi > Owen > >> thanks >> >> Luigi >> >> >> >>> Owen >>> >> >
