It should be pointed out that pre-provisioned AS_Path filters and prefix-lists would actually be effective at defeating this and preventing someone who is actually malicious from using this technique. This is an excellent argument for implementing SIDR...
Finally we agree. Although I am not certain SIDR is the optimal answer, we agree it would solve the problem.
The sidr wg is working on protection of the origination of the route - so the origin AS in the AS_PATH is known to be authorized to originate routes to the prefix. That's not full AS_PATH protection. sidr is not doing full AS_PATH protection. Yet. Protecting the origination is not sufficient, everyone recognizes that. But protecting the origination is necessary for eventual full AS_PATH protection, so we're not wasting our time, either. Feel free to chime in on the sidr list about wanting full path protection. As loud as you like. --Sandy