| The key thing here is that there is some kind of contractual agreement | between the second tier and the core members. If the second tier breaks | the agreement, their email flow is summarily cut off. You can do that | with contracts.
Yup.
As you've mentioned, we already have a mechanism for peering between providers - it's called BGP. Is it too much to ask for BGP peering contracts to include requirements to deal with abuse ?
Yes, I think that it is too much to ask for. Abuse has little to no impact on peering beyond minor traffic increments. Why should a BGP peering contract place a lot of importance on this? Certainly, BGP peering contracts do include some mention of abuse contacts and so on, but it is a side issue. However, when you consider email services, it is a different story. Whether it is abuse or whether it is shoddy email operations or whether it is misconfigured email server software, it WILL create major impacts on the quality of the email service. Most of this isn't even noticed by the NOC because they only care that packets flow smoothly. In order to improve the quality of Internet email service, we need more than the smooth flow of packets. We need the right packets in the right place at the right time, and only the right packets. --Michael Dillon