Ok, Larry, let me ask the $10,000 question:
If I announce 204.137.64/20 to you, how do you know if I am authorized to do so or not?
The answer is, absent something LIKE a NACR (ie: RR, RA, etc) you don't.
So now, if you *don't know*, do you take it or don't you?
I'm not arguing against NACRs and RAs. In fact, just the opposite. If you're going to filter, and I understand that it can serve a purpose, then you *MUST* trust some authoritative source, and that source must have the information to make the decision.
Even with a route registry, you have no way of knowing, apriora, that the registration is correct. There have already been "helpful" attempts to register information for others w/o their consent. Eric C. & I came up with this idea about the same time. I call it "Chain of Custody" and Eric has other names for it. In general, it depends on religious registration in whois and/or rwhois, the distributed IRR and PGP. Here is a brief summary: Basically, I have made a proposal to have the Internic set an example by registering all delegations in whois/RWhois and signing the delegation. All down-stream ISPs should do the same (register delegations in RWhois and sign any downstream delegations) When a custodian wishes to register a delegation for routing, they sign the request. That way, registry operators can follow a "chain of custody" to give priority when duplicate registration requests are entered into one or more registries. --bill