Drew Weaver <drew.weaver@thenap.com> inquired:
I know you all have probably already thought of this, but can anyone think of a feasible way to run a RBL list that does not have a single point of failure? Or any attackable entry?
Fedex. "Never underestimate the bandwidth of a station wagon loaded with DLT cartridges barreling along the highway at 70mph"... Seriously, as has already been pointed out, the distribution side of the equation is the easy part. Server admins can use an out-of-band technique like ordinary dialup to get access to the blocklist. But generating the blocklist requires real-time reporting back to a central server. Even if the server is decentralized, it will still require a relatively small handful of accessable IP addresses. An out of band layer-2 network could be created for that at the peering points, so as to prevent outside attack. Probably worth doing among major ISPs. Wouldn't scale to end users, of course. But end users could still subscribe to the blocklist through periodic updates. The other obvious thing that could be done would work pretty much like caller ID: create a set of SMTP enhancements that allow email recipients to accept mail from those who have provided traceable ID to the ISPs that participate, and who have agreed to acceptable-use policies that place strict limits on bulk email. Wait, hasn't that been done? The pre-1987 ARPAnet? Oh yeah, we've outgrown that... Public humiliation might also work. Bring back the stockades so we can place spammers out front of courthouses everywhere. Too bad society's outgrown that too... -rich