who gets a /32 [Re: IPV6 renumbering painless?]

Alex Bligh alex at alex.org.uk
Sat Nov 20 13:18:13 UTC 2004




--On 19 November 2004 09:40 -0800 Owen DeLong <owen at delong.com> wrote:

> If it were true, then I would have to renumber
> every time I changed telephone companies.  I don't, so, obviously, there
> is some solution to this problem.

But I'm not sure you'd like it applied to the internet. Firstly, in
essence, PSTN uses static routes for interprovider routing (not quite true,
but nearly - if you add a new prefix everyone else has to build it into
their table on all switches). Secondly, IIRC porting works in the UK
something like - call delivered to switch of operator who owns the block,
marked as ported number, lookup in central porting database (one for all
operators), operator port prefix put on dialed number, call sent back out
all the way to interconnect, enters new operator network, goes to switch
managing ports, further signalling info added to make call go to the
correct local switch, call goes to correct local switch, dross removed,
call terminated.

Roughly speaking this is the internet equivalent of:
* Configure all interprovider routes by a static routing config loaded
  every week or so.
* Handle porting by getting ICANN to run a box with a primative gated
  BGP feed connected to all your distribution routers. Where a packet
  is delivered to a distribution router and the IP address has changed
  providers, change the next hop received from the ICANN BGP feed
  to a GRE tunnel to the appropriate provider's tunnel termination box.
* At that tunnel termination box, static route all ported-in IP addresses
  to the correct distribution router.

Yum yum.

Sometimes we don't have lessons to learn from the PSTN world, and instead
the reverse is true.

Alex



More information about the NANOG mailing list