Re: Policy Statement on Address Space Allocations
| 1) Provider X can announce the aggregate outside of the area & thus | give free transit to the whole area; or | | 2) Provider X can announce just provider X's customers outside of the | area, thus defeating the gain from aggregation; or | | 3) Provider X can be paid by everyone else in the area to provide | transit to the entire area to where ever else Provider X connects to. Just to be vicious, I think I should mention option #4: Provider X can announce the aggregate outside of the area and drop packets bound for people in the area who do not pay Provider X for transiting packets to them. I think you will find that if a system were set up such that there were many touchdowns of this nature (announcing a single prefix), people would be screaming that they were at the mercies of the decisions about to whom in each local aggregate each long-distance carrier would be willing to deliver traffic. One could also view this as a way to push the problems of CIDRization out to the edges -- it would then be the end sites which would have to learn and be able to route towards the exceptions in the local aggregates, rather than the long-haul carriers. Sean.
| 1) Provider X can announce the aggregate outside of the area & thus | give free transit to the whole area; or | | 2) Provider X can announce just provider X's customers outside of the | area, thus defeating the gain from aggregation; or | | 3) Provider X can be paid by everyone else in the area to provide | transit to the entire area to where ever else Provider X connects to.
Just to be vicious, I think I should mention option #4: Provider X can announce the aggregate outside of the area and drop packets bound for people in the area who do not pay Provider X for transiting packets to them.
Option 5: Provider X can announce nothing outside the area, except to people who are paying X for transit to all X-reachable sites and networks. This would work great if all the backbones touch down in the area. Customers out in the Rest of the World get transit through their backbone to all the area sites. Other regional networks or areas get transit to it via whomever they get global transit from. It only gets really touchy if few of the backbones touch down in the area. I think that the intended target area (SF Bay Area) already has everyone of interest... getting this to work would merely require getting everyone to play in the party, not having anyone bring wires to the house. They're already here. -george
From : George Herbert <gherbert@crl.com>
Option 5: Provider X can announce nothing outside the area, except to people who are paying X for transit to all X-reachable sites and networks.
This would work great if all the backbones touch down in the area. Customers out in the Rest of the World get transit through their backbone to all the area sites. Other regional networks or areas get transit to it via whomever they get global transit from.
Which works fine as long as only one area on the planet ever implements Option 5. Any pair of such areas without internal connectivity won't be able to talk. Seems like a scaling problem. Dennis Ferguson
Option 5: Provider X can announce nothing outside the area, except to people who are paying X for transit to all X-reachable sites and networks.
This would work great if all the backbones touch down in the area. Customers out in the Rest of the World get transit through their backbone to all the area sites. Other regional networks or areas get transit to it via whomever they get global transit from.
Which works fine as long as only one area on the planet ever implements Option 5. Any pair of such areas without internal connectivity won't be able to talk. Seems like a scaling problem.
No, they can talk just fine. In the worst case with asymetric paths, but they can talk fine. Backbones A and B, small providers a in region 1 and z in region 2. a buys transit to the world from A and is in the region 1 block. z buys transit to the world from B ans is in the region 2 block. a->z goes a->A. A knows about region 2 block, sends it to region 2. Once it reaches there, it either goes A->B->z or A->z if there is a direct interconnect somewhere. z->a goes out the z->B pipe, and thence to region 1 and either B->A->a or B->a if there is a direct interconnection somewhere. -george
participants (3)
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Dennis Ferguson -
George Herbert -
Sean Doran