INTERNET-DRAFT R. Hinden, Ipsilon Networks July 16, 1997 M. O'Dell, UUNET TLA and NLA Assignment Rules 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 1id-abstracts.txt listing contained in the internet- drafts Shadow Directories on nic.ddn.mil, nnsc.nsf.net, nic.nordu.net, ftp.nisc.sri.com, or munnari.oz.au to learn the current status of any Internet Draft. This internet draft expires on January 17, 1998. 1.0 Introduction This document defines assignment rules for Top-Level Aggregation Identifiers (TLA ID) and Next-Level Aggregation Identifiers (NLA ID) as defined in [AGGR]. These rules apply to registries allocating TLA ID's and to organizations receiving TLA ID's. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC 2119]. draft-ietf-ipngwg-tla-assignment-00.txt [Page 1] INTERNET-DRAFT TLA and NLA Assignment Rules July 1997 2.0 IPv6 Aggregatable Global Unicast Address Format This document defines assignment rules for the TLA ID and NLA ID fields in the IPv6 Aggregatable Global Unicast Address Format. This address format is designed to support both the current provider-based aggregation and a new type of exchange-based aggregation. The combination will allow efficient routing aggregation for sites that connect directly to providers and for sites that connect to exchanges. Sites will have the choice to connect to either type of aggregation entity. While this address format is designed to support exchange-based aggregation (in addition to current provider-based aggregation) it is not dependent on exchanges for it's overall route aggregation properties. It will provide efficient route aggregation with only provider-based aggregation. The aggregatable global unicast address format as defined in [AGGR] is as follows: | 3 | 13 | 32 | 16 | 64 bits | +---+-----+-----------+--------+--------------------------------+ |FP | TLA | NLA ID | SLA ID | Interface ID | | | ID | | | | +---+-----+-----------+--------+--------------------------------+ <--Public Topology---> Site <--------> Topology <------Interface Identifier-----> Where FP Format Prefix (001) TLA ID Top-Level Aggregation Identifier NLA ID Next-Level Aggregation Identifier SLA ID Site-Level Aggregation Identifier INTERFACE ID Interface Identifier 3.0 Rules for Assignment of Top-Level Aggregation ID's TLA ID's are assigned to organizations providing public transit topology. They are specifically not assigned to organizations only providing leaf or private transit topology. TLA ID assignment does not imply ownership. It does imply stewardship over valuable Internet property. draft-ietf-ipngwg-tla-assignment-00.txt [Page 2] INTERNET-DRAFT TLA and NLA Assignment Rules July 1997 The IAB and IESG have authorized the Internet Assigned Numbers Authority (IANA) as the appropriate entity to have the responsibility for the management of the IPv6 address space as defined in [ALLOC]. The IANA will assign small blocks of TLA ID's to IPv6 registries. The registries will assign the TLA ID's to organizations meeting the requirements for TLA ID assignment. When the registries have assigned all of their TLA ID's they can request that the IANA give them another block. The blocks do not have to be contiguous. The IANA may also assign TLA ID's to organizations directly. Registries are required to insure that organizations assigned TLA ID's meet the following requirements: - Must have a plan to offer public native IPv6 service within 6 months from assignment. The plan must include plan for NLA ID allocation. - Must have a plan or track record of providing public Internet transit service on fair, reasonable, and non-discriminatory terms, to other providers. TLA ID's must not be assigned to organizations that are only providing leaf service even if multihomed. - Must provide registry services on fair, reasonable, and non- discriminatory terms, for the NLA ID address space it is responsible for under its TLA ID. This must include both sites and next level providers. - Must provide transit routing and forwarding to all assigned TLA ID's on fair, reasonable, and non-discriminatory terms. Organizations are not allowed to filter out any specific TLA ID's (except temporarily for diagnostic purposes or emergency repair purposed). - Periodically (interval set by registry) provide to registry utilization statistics of the TLA ID it has custody of. The organization must also show evidence of carrying TLA routing and transit traffic. This can be in the form of traffic statistics, traceroutes, routing table dumps, or similar means. Organizations which are given custody of a TLA ID and fail to continue to meet these may have the TLA ID custody revoked. draft-ietf-ipngwg-tla-assignment-00.txt [Page 3] INTERNET-DRAFT TLA and NLA Assignment Rules July 1997 4.0 Rules Assignment of Next-Level Aggregation ID's Next-Level Aggregation ID's are used by organization assigned a TLA ID to create an addressing hierarchy and to identify sites. The organization can assign the top part of the NLA ID in a manner to create an addressing hierarchy appropriate to its network. Organizations assigned TLA ID's are required to assume registry duties for the NLA ID's they assign. Each organization assigned a NLA ID is required to assume registry duties for the next level NLA ID's it assigns. The design of the bit layout of the NLA ID space for a specific TLA ID is left to the organization responsible for that TLA ID. Likewise the design of the bit layout of the next level NLA ID is the responsibility of the organization assigned the previous level NLA ID. It is recommended that organizations assigning NLA address space use "slow start" allocation procedures as is currently done with IPv4 CIDR blocks [CIDR]. The design of an NLA ID allocation plan is a tradeoff between routing aggregation efficiency and flexibility. Creating hierarchies allows for greater amount of aggregation and results in smaller routing tables. Flat NLA ID assignment provides for easier allocation and attachment flexibility, but results in larger routing tables. 5.0 Acknowledgments The authors would like to express our thanks to Thomas Narten, Bob Fink, Matt Crawford, Allison Mankin, Jim Bound, Christian Huitema, Scott Bradner, Brian Carpenter, and John Stewart for their review and constructive comments. 5.0 References [AGGR] Hinden, R., Deering, S., O'Dell, M., "An Aggregatable Global Unicast Address Format", Internet Draft, , July 1997. [ALLOC] IAB and IESG, "IPv6 Address Allocation Management", RFC1881, December 1995. [ARCH] Hinden, R., "IP Version 6 Addressing Architecture", Internet Draft, , July 1997. draft-ietf-ipngwg-tla-assignment-00.txt [Page 4] INTERNET-DRAFT TLA and NLA Assignment Rules July 1997 [AUTH] Atkinson, R., "IP Authentication Header", RFC1826, August 1995. [CIDR] Fuller, V., T. Li, K. Varadhan, J. Yu, "Supernetting: an Address Assignment and Aggregation Strategy", RFC1338. [IPV6] Deering, S., Hinden, R., Editors, "Internet Protocol, Version 6 (IPv6) Specification", RFC1883, December 1995. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC2119, BCP14, March 1997. 6.0 Security Considerations IPv6 addressing documents do not have any direct impact on Internet infrastructure security. Authentication of IPv6 packets is defined in [AUTH]. 7.0 Authors' Addresses Robert M. Hinden phone: 1 408 990-2004 Ipsilon Networks, Inc. email: hinden@ipsilon.com 232 Java Drive Sunnyvale, CA 94089 USA Mike O'Dell phone: 1 703 206-5890 UUNET Technologies, Inc. email: mo@uunet.uu.net 3060 Williams Drive Fairfax, VA 22030 USA draft-ietf-ipngwg-tla-assignment-00.txt [Page 5]