Rob's bogon lists are good, but unless you have the processes in place to keep it update to date (or hire an consulting firm to do it for you), its about as useful as putting a list of "invalid" phone numbers in your PBX. The lists change all the time, and unless you are a full-time LERG expert, it will probably get quickly out of date.

Of course, we can always use LDAP to keep all the PBX's updated.

Well, we use DNS to keep all of our resolvers updated with the latest IP address changes and it works so well that most people never even think about what is happening under the hood unless they are renumbering. Compare this to what happens when the root hints file changes. In that case you need processes and people or, more likely, you wait until something breaks and then hire a consultant who updates your root hints file for a nice fee. This is not the model I would use to solve the bogon problem. --Michael Dillon