On 27-mei-2007, at 0:10, Simon Leinen wrote:
ISPs generally feel strongly about their rights to decide for themselves with which other ISPs they want to peer (settlement-free).
And rightly so.
Proponents of new schemes should make it very clear that they won't take this right away from ISPs, if they want buy-in from that community. Personally I think geographical addressing could lead to better aggregation, even without imposing full interconnection (settlement-free or not :-) within a geographic region.
If you only peer in one location for traffic towards a certain geopgraphic area, then routing is simple and very scalable: in theory, only one router in that specific location has to know all the specific routes for that geographic area; all other routers only see an aggregatte.
Today, all default-free routers must know all the specific routes for the entire world.
The first extreme is obviously bad for business for ISPs (not to mention fragile, what if your single location becomes unreachable?) and the other extreme has scalability issues (as a matter of principe--whether it keeps working in practice is a different question). Some kind of knob that allows an ISP to move from one extreme to the other would allow the level of geographic aggregation to be traded off against investments in more or larger routers or less optimal traffic flow, making it a business problem for ISPs rather than an engineering problem for router vendors.