Dear RIPE NCC Services-WG, please have a look at a new proposal: _Purpose: optimize Reverse-DNS operations_ 1. Assumption: There is a ton of negative reverse-DNS replies (no PTR-record/NXDOMAIN) returned from the RIPE NCC rev-DNS-Servers, for all not-yet-delegated address-blocks they are responsible for (also called “lame” delegations ?). 2. Question: How could this be optimized or at least encouraged to be fixed? Proposal: The RIPE NCC ops starts collecting statistics per member/LIR account of negative reverse-DNS queries for a respective address block (which is not yet delegated) and reports those statistics optionally to the LIRs, sorted by amount (i.e. top10 or top20 list in a fixed interval - say 1/month). There should be NO information about WHO requested rev-DNS values or when. Just a simple, aggregated summary of top requested addresses/blocks. 3. In case a member opts-in to view such statistics, one could decide to actively reply to such reverse-DNS requests and instead offer “good results” for requests, the address owners would never would see. 4. As a result: better performance, less errors through better infomation for RIR-members. I propose to run a test with a given address-block, which are not yet reverse-delegated and check if this approach is feasable, or where breakpoints might be, if this needs to work at a larger scale (across all rev-DNS Servers, operated by RIPE NCC for many members ideally). Best regards, Kurt Kayser