North American Network Operators Group

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Re: IPv6 news

  • From: Paul Jakma
  • Date: Tue Oct 18 11:02:00 2005

On Tue, 18 Oct 2005, Andre Oppermann wrote:

Yes, but it's a very cumbersum process. You have to track this stuff for all regions and countries. They all vary how they do it. For example your ComReg publishes a couple of tables now and then with new/changed information. (Look for ComReg 04/35, 03/143R, etc.)
Presumably, for IP, we'd use databases and processes more typical to normal IP ops, eg RIR databases and such, to record which ISPs can service which geo-prefixes. The subscriber_prefix->provider information itself can just be dynamically routed locally.

SS7 over IP is quite popular these days. However call routing != SS7 message routing.
By call-routing you mean the actual circuit switching of each call? I don't mean that, I mean the number routing, which SS7 /does/ do - you referred to it as being more analogous to DNS iirc in operation.

IP routing is not symmetric whereas circuit switching is. In a case of individual IP address portability the return traffic always goes back to the ISP who has that particular prefix. No matter who 'opened' the connection. If I port my static dial-up IP to my new super FTTH ISP then suddenly up to 100Mbit of return traffic have to pass from Dial-Up ISP to FTTH ISP. I'd say this screws the Dial-Up ISP pretty royally. And you too because he most likely doesn't have that much capacity.
Ah, multi-homed. We havn't considered this case yet, but in the above, you're a customer of both these ISPs. I'd say the dial-up ISP would ask you sharpish to relist your "home" ISP as the FTTH ISP while charging you for that 100Mb/s of traffic (as the contract would provide for).

The same thing can happen today with multihomed PI customers - what would happen today?

Nope, it's not.  Can you name a phone prefix routing protocol?
Ehm, SS7 ;).

You might call it DNS-like because it's request based, but it still provides routing information.

However there is no dynamic call routing as we know it from BGP or OSPF. At least not directly. Some switch vendors have developed call optimization software which runs in some sort of central intelligence center in the network and tries to optimize the trunk usage and priorities based on statistical and historical data.
I meant only the routing information, not the switching (which is clearly completely different in packet switched IP).

The stumbling block is that all IP packets return to the prefix
holder (the old ISP) and the end-user bandwidth is not fixed.
See above, what happens today? Multihomed sites can already try screw upstreams in this way, so no difference.

$RIR making allocations that way is not sufficient. It would need regulatory backing to enforce IP address portability.

Every established carrier is not very interested in porting IP addresses to competitors.
Why not, if you can money off it. Two-edged sword too, if you must easily port addresses to competitors you can get their customers more easily too.

Whether this is the right solution depends on whether ISPs would prefer such a mechanism to end-host based solutions. I can't answer that question.

Paul Jakma [email protected] [email protected] Key ID: 64A2FF6A
If you stand on your head, you will get footprints in your hair.