Proper "good net neighbor" egress filtering of RFC1918 source addresses takes a number of separate rules. Several 'allows', followed by a default 'deny'.
Really? Do you have those rules on your network? Any reason why you didn't post the operational details on this operational list? Have you ever read your peering agreements or service contracts to see if filtering of RFC 1918 sourced traffic is specifically covered by them? If it is not covered by the contract, then why should your peers/upstreams filter it? Another good question is whether or not every service contract and peering agreement should contain unique text or whether there should be some community-developed best practices statement that could be plugged in by reference. For instance, software publishers can publish their software under the terms of the GPL without including the full text of the GPL verbatim in their software license. Does NANOG have a role in developing some best practices text that could be easily imcorporated into peering agreements and service contracts? --Michael Dillon