Network Working Group P. Tsuchiya INTERNET-DRAFT S. Thomson Bellcore January 1993 Use of DNS with Pip Status of this Memo This document is an Internet Draft. Internet Drafts are working documents of the Internet Engineering Task Force (IETF), its Areas, and its Working Groups. Note that other groups may also distribute working documents as Internet Drafts). Internet Drafts are draft documents valid for a maximum of six months. Internet Drafts may be updated, replaced, or obsoleted by other documents at any time. It is not appropriate to use Internet Drafts as reference material or to cite them other than as a "working draft" or "work in progress." Please check the I-D abstract listing contained in each Internet Draft directory to learn the current status of this or any other Internet Draft. Abstract Pip is an internet protocol intended as the replacement for IP version 4. Pip is a general purpose internet protocol, designed to handle all forseeable internet protocol requirements. This specification describes the use of DNS to support Pip. Because Pip carries IDs and addresses separately, and because Pip Addresses are variable length, DNS must be modified to support Pip. In addition to these necessary modifications, we have chosen to add new elements to DNS in order to support additional functions, such as policy routing, mobile hosts, routing through Public Data Networks, and transition. Later multicast support will be added as well (for CBT). Acknowledgements The authors would like to acknowledge Bob Smart and Garrett Wollman for their initial work on Pip in DNS. Pip WG, Expires July. 15, 1993 [Page 1] INTERNET-DRAFT Pip DNS January 1993 Conventions All functions in this specification are mandatory. 1. Introduction Pip is an internet protocol intended as the replacement for IP ver- sion 4. Pip is a general purpose internet protocol, designed to han- dle all forseeable internet protocol requirements. This specifica- tion describes the use of DNS to support Pip. Because Pip carries IDs and addresses separately, and because Pip Addresses are variable length, DNS must be modified to support Pip. In addition to these necessary modifications, we have chosen to add new elements to DNS in order to support additional functions, such as policy routing, mobile hosts, routing through Public Data Networks, and transition. Later multicast support will be added as well (for CBT). In spite of this additional functionality, we retain the fundamental DNS paradigm of source-independency (this DNS record is returned to the queryer no matter who the queryer is). We also retain the funda- mental DNS paradigm that the information stored by DNS does not change often. This draft is still rough, and subject to change and expansion. Com- ments are very welcome. 2. SUMMARY OF THE PIP DNS INFORMATION Following is a summary of the information in DNS for Pip. 1. One or more Pip IDs (though usually just one). 2. Multiple Pip addresses. While these addresses are returned in a DNS Answer as complete addresses, in the DNS files they are par- titioned as external and internal parts (external is the high- order part of the pip address that is assigned to it by the private domain's carrier. Internal is the low-order part of the pip address that is assigned by the private network. Generally a Pip host will have a single low-order part, but may have Pip WG, Expires July. 15, 1993 [Page 2] INTERNET-DRAFT Pip DNS January 1993 multiple high-order parts.) 3. Public data network address. This tells, in the case where the destination is reachable via a major public data network (PDN) service, what the public data network address (such as E.164) is. This can be put in an option of the Pip header, and subse- quently used by the ingress Pip router. 4. Mobile Address Server. For the case where the destination is a mobile host, this would contain the domain name of a server that knows the current location of the mobile host. In the case where a host is predominantly mobile (that is, doesn't have a "normal" reachable address), the Pip address part may be null, and this part filled in. In the case where the server address and normal address of the host is the same, this record may be excluded. 5. Descriptive information associated with the backbone represented by the Pip Address. The purpose of this information is to allow the source to make a policy decision. The descriptive info will include backbone type (internet, frame relay, smds, etc.), res- triction class (commercial, research, etc.), available Type of Service (TOS) (full-motion video, voice, telnet, etc.), and pro- vider name (ANS, AT&T, etc.). The purpose of this is to give information that is useful and sufficient for the large majority of users, but not necessarily satisfy every possible policy requirement. This information will allow the source to choose the best source and destination providers for a given communica- tions. 6. The domain name of a Pip/IP translator for the destination. This is used in the case where the destination is an IP-only, and so the Pip header must be addressed to the Pip/IP translator positioned at the border between the IP domain and the Pip domain. Note that in the case where both source and destination are IP-only, with Pip in the middle, the entry Pip/IP translator must do a DNS query to obtain this information. 3. SPECIFICATION OF QUERY AND RECORD TYPES The following types are the new types of resource records we are Pip WG, Expires July. 15, 1993 [Page 3] INTERNET-DRAFT Pip DNS January 1993 adding to DNS. Note that query types are a superset of resource record types, and hence any resource record type is a valid query type. Type Value and Meaning ---- ----------------- PID 64 Pip identifier PA 65 Pip address MS 66 Mobile host server BBD 67 Backbone descriptor PDNA 68 PDN attachment point address TRAN 69 Name of Pip/IP translation gateway In addition, the following special-purpose query types are added: ADDR_SOME 250 A request for Pip identifiers and some address information (A, PID, PA) ADDR_ALL 251 A request for all identifying and address-related information (A, PID, PA, MS, TRAN) 3.1. Resource Record (RR) definitions PID data format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | PIPID | | | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: PIPID A 64-bit Pip identifier represented in its modified ASN.1 notation (see specification on Pip Identifiers). PID RRs cause no additional section processing. PA data format Pip WG, Expires July. 15, 1993 [Page 4] INTERNET-DRAFT Pip DNS January 1993 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / PA / / / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: PA A Pip address, consisting of a sequence of FTIFs, each one represented by a 32-bit word. PA RRs do cause additional section processing. PDN attachment point addresses are returned in the additional section. MS data format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / MS / / / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: MS A of the host acting as the mobile server for the specified domain. MS RRs do cause additional section processing. An ADDR_SOME query is done on the domain name of the mobile host server. TRAN data format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / TRAN / / / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: TRAN A of the Pip/IP translation gateway that is to be used for the specified domain. TRAN RRs do cause additional section processing. An ADDR_SOME query is done on the domain name of the Pip/IP translation gateway. Pip WG, Expires July. 15, 1993 [Page 5] INTERNET-DRAFT Pip DNS January 1993 BBD data format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | reserved | CHARSET | NUMCLASS | NUMTOS | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / BBNAME / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / BBTYPE / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / BBCLASS / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / BBTOS / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: An 8-bit reserved field. CHARSET An 8-bit field indicating the character set used in the BBD text fields. NUMCLASS An 8-bit field indicating the number of user classes in the BBCLASS field. NUMTOS An 8-bit field indicating the number of TOS descriptors in the BBTOS field. BBNAME A which specifies the backbone (provider) name. BBTYPE A which specifies the backbone type. BBCLASS A sequence of s, each of which specifies a user class descriptor. BBTOS A sequence of TOS descriptors as defined below: +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / TOSTYPE / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | OBJNAME | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: TOSTYPE A which specifies the TOS type. OBJNAME A which specifies a Pip object name. Standard values for character sets, names, classes and types must Pip WG, Expires July. 15, 1993 [Page 6] INTERNET-DRAFT Pip DNS January 1993 still be defined. BBD resource records are associated with a particular Pip address using a reverse lookup domain (see below). This record causes no additional section processing. PDNA data format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / PDNADDR / / / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: PDNADDR A which specifies the public data network attachment point address. PDNA resource records are associated with a particular Pip address using a reverse lookup domain (see below). This record causes no additional section processing. 3.2. PIP-ADDR.ARPA and PIP-ID.ARPA domains The above two special domains are used to map PIP addresses and PIP identifiers to regular domain names, respectively. As with IP4 addresses, the PTR resource record type is used to query this map- ping. Note that PTR types cause no additional section processing. Pip addresses are represented by a sequence of decimal FTIF values in reverse order with the suffix PIP-ADDR.ARPA. Pip identifiers are represented by hex labels in reverse order, with the suffix PIP- ID.ARPA. These labels are determined from the hierarchical structure of the Pip identifier. Pip address and identifier labels are separated by dots. Pip WG, Expires July. 15, 1993 [Page 7] INTERNET-DRAFT Pip DNS January 1993 The PIP-ADDR.ARPA domain is also used to map Pip addresses to back- bone descriptors (BBD type) and PDN attachment point addresses (PDNA type). 3.3. Special-purpose Query Types The ADDR_SOME query type A query on a regular domain name of this type causes resource records of type A, PID and PA to be returned. Since PA queries do type PDNA additional section processing, PDNA information corresponding to each physical address will be returned in the additional section. The ADDR_ALL query type A query on a regular domain name of this type causes resource records of type A, PID, PA, MS and TRANS to be returned. Since PA, MS and TRANS queries do additional section processing, PDNA information corresponding to each physical address will be returned as well as address information (defined by the ADDR_SOME type) associated with the domain's mobile host server and Pip/IP translation gateway. 3.4. Modifications to Existing Resource Record Definitions NS, MX and MB resource record definitions will be modified to cause type ADDR_SOME additional section processing, rather than type A additional section processing. Otherwise, these definitions remain the same. Pip WG, Expires July. 15, 1993 [Page 8]