I reread this and still don't see how geographical ip address allocation is going to work if typical customer connections are network-centric and any large area has number of competitive access providers (unless you're fine with multiple providers announcing aggregate summary in anycast fashion). The only way I see that geographical addressing might have some advantage is if the area is covered by large monopoly that connects everyone else there (and its not to say that such situation does not exist in some countries, but I don't think this situation should be encouraged and forced to continue forever with network allocation policies). On Tue, 18 Oct 2005 Michael.Dillon@btradianz.com wrote:
Here, the suggestion is that netblocks should be allocated to cities, not to providers. Within
I am a multihomed customer and my ISPs are in two different cities. What are my IP addresses going to be?
Your assumptions are flawed. I never suggested that there would be a flag day. I never suggested that geotopological addressing would work everywhere or solve all problems. I never suggested that we should turn off the existing provider aggregatable IP address allocations.
I just suggested an alternative way of issuing addresses so that they are geotopologically aggregatable, not provider aggregatable. There are sufficient reserved addresses in the IPv6 address space to do this. We could start issuing geotopological netblocks and try it for 5 years or so to see whether it works better or not.
In any case, you are located in Montreal which is such a major city that I expect any ISP selling service (geotopologically) in Montreal would use Montreal address space even if they backhauled at layer two to some other city.
However, there will likely be lots of situations where people in small towns roughly equidistant from two cities will choose to multihome with links to separate cities. This will either have to be done using provider-aggregated addresses or by using addresses from one of the cities with a longer prefix inside that city's routing table to direct the traffic to the neighboring city. If this is suboptimal, it won't be by much considering that these are neighboring cities.
I'm not suggesting any change to IPv6 stacks or to routing protocols. I'm just suggesting that we could allocate the same IPv6 addresses to operators in a way that allows geotopological aggregation rather than the existing provider aggregation. Combine this with local traffic exchange in every city and you have a more robust Internet with lower overall latency that will run with a smaller global routing table.
I know that some individual operators, such as the one I work for, have very robust IP networks with low overall latency. But when we talk about the Internet, then we include all the private interconnects and public exchange points and tromboning of traffic due to peering "issues", etc.
--Michael Dillon
-- William Leibzon Elan Networks william@elan.net