Folks, Here's the updated document. I was planning on sending this out over the weekend, but forgot the modem cable ;-( Anyway, let's see if we can get agreement on this. Please note that the database specific things I do not want to spend too much on, this should be done at the RIPE meeting. A few more days to comment. Want to start delegating blocks end of the week, and during next week (although I will be at the IETF). -Marten Guidelines for the delegation of class C blocks in the 193.in-addr.arpa domain Marten Terpstra March 1993 V1.1 Introduction This document describes the procedures for the delegation of authority of zones in the 193.in-addr.arpa domain. As of March 16th 1993 the RIPE NCC has been delegated the authority for the 193.in-addr.arpa domain from the root. Due to the fact that in the 193.x.y address space blocks of 256 class C network numbers are further delegated to local registries and national registries, the possibility exists to also delegate the zone for these blocks in the 193.in-addr.arpa domain. This document describes some guidelines and procedures for this type of delegation. A bit more explained With the assignment of class C network numbers following the CIDR (RFC 1338) model, in which large chunks of the address space are delegated to one region, and within that region blocks of class C network numbers are delegated to service providers and national registries, some hierarchy in the address space is created, similar to the hierarchy in the domain name space. Due to this hierarchy the reverse Domain Name System mapping can also be delegated in a similar model as used for the normal Domain Name System. For instance, the RIPE NCC has been delegated the complete class C address space starting with 193. It is therefore possible to delegate the 193.in-addr.arpa domain completely to the RIPE NCC, in stead of each and every reverse mapping in the 193.in-addr.arpa domain to be registered with the INTERNIC. This implies that all 193.in-addr.arpa resistrations will be done by the RIPE NCC. Even better, since service providers receive complete class C network blocks from the RIPE NCC, the RIPE NCC can delegate the reverse registrations for such complete blocks to these local registries. This implies that customers of these service providers no longer have to register their reverse domain mapping with the root, but the service provider have authority over that part of the reverse mapping. This decreases the workload on the INTERNIC and the RIPE NCC, and at the same time increase the service a provider can offer its customers and response times for such additions. However there are some things that need to be examined a bit more closely to avoid confusion and inconsistencies. These issues are covered in the next section. Procedures 1. A secondary nameserver at ns.ripe.net is mandatory for all blocks of class C network numbers delegated in the 193.in-addr.arpa domain. 2. Because of the increasing importance of correct reverse address mapping, for all delegated blocks a good set of secondaries must be defined. There should be at least 2 nameservers for all blocks delegated, excluding the RIPE NCC secondary. 3. The delegation of a class C block in the 193.in-addr.arpa domain can be requested by sending in a domain object for the RIPE database to <hostmaster@ripe.net> with all necessary contact and nameserver information. The RIPE NCC will then forward all current reverse zones inside this block to the registry, and after addition by the registry, the NCC will check the working of the reverse server. Once everything is setup properly, the NCC will delegate the block, and submit the database object for inclusion in the database. An example domain object can be at the end of this document. 4. All reverse servers for blocks must be reachable from the whole of the Internet. In short, all servers must meet similar connectivity requirements as top-level domain servers. 5. Running the reverse server for class C blocks does not imply that one controls that part of the reverse domain, it only implies that one administers that part of the reverse domain. 6. Before adding individual nets, the administrator of a reverse domain must check wether all servers to be added for these nets are indeed setup properly. 7. There are some serious implications when a customer of a service provider that uses address space out of the service provider class C blocks, moves to another service provider. The service provider cannot force its ex-customer to change network addresses, and will have to continue to provide the appropriate delegation records for reverse mapping of these addresses, even though it is no longer a customer of his. 8. The registration of the reverse zones for individual class C networks will usually be done by the registry administering the class C block this network has been assigned from. The registry will make the necessary changes to the zone, and update the network objects in the RIPE database for these networks, to reflect the correct "rev-srv" fields. In case the RIPE NCC receives a request for the reverse zone of an individual class C network out of a block that has been delegated, the request will be forwarded to the zone contact for this reverse block. Above procedures are defined to ensure the necessary high availability for the 193 reverse domains, and to minimize confusion. The NCC will ensure fast repsonse times for addition requests, and will in principle update the 193.in-addr.arpa domain at least once per working day. The NCC also suggests that similar procedures are set up for the delegation of reverse zones from the registries to individual organisations. Example domain object to request a block delegation domain: 202.193.in-addr.arpa descr: Pan European Organisations class C block admin-c: Daniel Karrenberg tech-c: Marten Terpstra zone-c: Marten Terpstra nserver: ns.eu.net nserver: sunic.sunet.se nserver: ns.ripe.net changed: marten@ripe.net 930319 source: RIPE