In message <18974_1354801737_50c0a249_18974_12639_1_5c4880217cbf5346a0c211c7dab9140104e...@pexcvzym14.corporate.adroot.infra.ftgr oup>, [email protected] writes: > All, > > In the document draft-howard-isp-ip6rdns-05, a proposal to manage the > ip6-addr.arpa zone is to generate a PTR record on demand, and cache or > prepopulate the forward (AAAA) entry for the duration of the time-to-live > of the PTR. > > It is possible to generate PTR responses to reverse lookups on the fly > without need to keep the forward entry into cache memory. > > > Kazunori Fujiwara has implemented a prototype "On the Fly" DNS server > which does not require caching. > > > > http://member.wide.ad.jp/~fujiwara/v6rev.html > > > The algorithm is simple. The DNS server builds the reverse host name as > the concatenation of the IPv6 address (using a 32-character hexadecimal > representation without :) with a fixed domain name suffix. > The generated hostname can be easily resolved by forward lookup since the > generated hostname contains raw IPv6 address. The response is in the > question. > > Here below an example of reverse lookup matching a forward lookup. > > The reverse lookup on IPv6 "2a01:c012:3456:789a:bcde:f012:3456:789a" > gives the following: > > # dig -x 2a01:c012:3456:789a:bcde:f012:3456:789a +short > 2a01c0123456789abcdef0123456789a.ip6.abo.orange.fr. > > In the forward lookup response, we retrieve the original IPv6 address: > > # dig 2a01c0123456789abcdef0123456789a.ip6.abo.orange.fr -t aaaa +short > 2a01:c012:3456:789a:bcde:f012:3456:789a > > > Philippe Lemordant
While it is staight forward enough to do this technically it is still *not* a good idea to deploy it. ISP's have leased the address to their customers and for the duration of that lease the CUSTOMER not the ISP should be the one naming the machine. When ISPs started doing this with IN-ADDR.ARPA the protocols necessary to have machines populate the zone themselves did not exist. A lot has changed in the intervening years. > __________________________________________________________________________ > _______________________________________________ > > Ce message et ses pieces jointes peuvent contenir des informations > confidentielles ou privilegiees et ne doivent donc > pas etre diffuses, exploites ou copies sans autorisation. Si vous avez > recu ce message par erreur, veuillez le signaler > a l'expediteur et le detruire ainsi que les pieces jointes. Les messages > electroniques etant susceptibles d'alteration, > France Telecom - Orange decline toute responsabilite si ce message a ete > altere, deforme ou falsifie. Merci. > > This message and its attachments may contain confidential or privileged > information that may be protected by law; > they should not be distributed, used or copied without authorisation. > If you have received this email in error, please notify the sender and > delete this message and its attachments. > As emails may be altered, France Telecom - Orange is not liable for > messages that have been modified, changed or falsified. > Thank you. -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: [email protected] _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
