Colleagues, This is a technical, operational announcement regarding changes to the ARPA top-level domain. Apologies in advance for duplicates received through different mailing lists. No specific action is requested of operators. This message is for your information only. The ARPA zone is about to be signed using DNSSEC. The technical parameters by which ARPA will be signed are as follows: KSK Algorithm and Size: 2048 bit RSA KSK Rollover: every 2-5 years, scheduled rollover to follow RFC 5011 KSK Signature Algorithm: SHA-256 Validity period for signatures made with KSK: 15 days; new signatures published every 10 days ZSK Algorithm and Size: 1024 bit RSA ZSK Rollover: every 3 months ZSK Signature Algorithm: SHA-256 Authenticated proof of non-existence: NSEC Validity period for signatures made with ZSK: 7 days; zone generated and re-signed twice per day The twelve root server operators [1] will begin to serve a signed ARPA zone instead of the (current) unsigned ARPA zone during a maintenance window which will open at 2010-03-15 0001 UTC and close at 2010-03-17 2359 UTC. Individual root server operators will carry out their maintenance at times within that window according to their own operational preference. The trust anchor for the ARPA zone will be published in the ITAR [2], and in the root zone in the form of a DS record once the root zone is signed. If you have any concerns or require further information, please let me know. Regards, Joe Abley Director DNS Operations, ICANN [1] http://www.root-servers.org/ [2] https://itar.iana.org/