Hi, On Mon, Apr 24, 2006 at 09:39:30AM +0100, Nick Hilliard wrote:
Gert Doering wrote:
The nice thing about Internet (as opposed to the telephone system) is the fact that we have DNS - and thus no need to take our "numbers" with us to be reachable.
This is certainly the theory. However, if you are a growing ISP, renumbering from PA space from another LIR to your own PI space or LIR/PA space can be - depending on how your customers are configured - pure pain.
Yes. Been there, done that. Couple of times (renumbering an ISP's recursive name servers is *very much* pain). But that's local pain. PI is global pain to everybody else.
The portability associated with PI space is also important in one other view, in that it allows the holder to switch providers quickly and efficiently. There's no tie-in of any form, and this is something which is extremely important to business.
This is the standard argument, but only half-true. For serious internet connections, you usually need to move your leased-line connection, or move your servers to a new colocation - which is, assuming ``standard'' setups and some planning in advance, comparable if not more effort to changing the addresses. A poorly planned network, with everything hardcoded everywhere (up to applications that access IP addresses hard-coded in the source) is not a proper excuse to burden everbody else's routers. I accept that PI for BGP multihoming purposes is - today - one of the more reasonable ways to achieve the goal (ISP independence and resilience), but I still hope that we won't ever see the "let's get PI once, and never have to renumber again!" land rush. Gert Doering -- NetMaster -- Total number of prefixes smaller than registry allocations: 92315 SpaceNet AG Mail: netmaster@Space.Net Joseph-Dollinger-Bogen 14 Tel : +49-89-32356-0 D- 80807 Muenchen Fax : +49-89-32356-234