Internet Engineering Task Force Y. Shirasaki, Ed. Internet-Draft S. Miyakawa Expires: May 3, 2009 NTT Communications A. Nakagawa KDDI CORPORATION J. Yamaguchi IIJ H. Ashida iTSCOM October 30, 2008 ISP Shared Address draft-shirasaki-isp-shared-addr-01 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. 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 and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on May 3, 2009. Copyright Notice Copyright (C) The IETF Trust (2008). Abstract This document defines IPv4 ISP Shared Address to be jointly used among Internet Service Providers (ISPs). This space is intended to Shirasaki, et al. Expires May 3, 2009 [Page 1] Internet-Draft ISP Shared Address October 2008 enable ISPs' continuous IPv4 based operation even after the IPv4 address exhaustion. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. ISP Shared Address . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Details . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Size of Address Space . . . . . . . . . . . . . . . . . . . . . 4 4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 5 Intellectual Property and Copyright Statements . . . . . . . . . . 8 Shirasaki, et al. Expires May 3, 2009 [Page 2] Internet-Draft ISP Shared Address October 2008 1. Introduction IPv4 Global address is said to be run out soon. Unless ISP takes any action, it will not be able to provide the service to new customers. To expand ISP's business, ISP has to continue assigning IPv4 address to its network. Thus, under the condition of the IPv4 Global address exhaustion, ISP needs alternative address block. This document defines ISP Shared Address for this purpose. It is used between Customer Premises Equipment (CPE) and Carrier Grade NAT [I-D.nishitani-cgn] (CGN) in a NAT444 network model [I-D.shirasaki-nat444-isp-shared-addr]. ISP Shared Address is needed until the IPv4 Internet fades out. 2. ISP Shared Address 2.1. Definition ISP Shared Address is intended to be assigned between CPE and CGN in a NAT444. 2.2. Details - Each ISP can use ISP Shared Address without any coordination with IANA or Internet registries. - ISP Shared Address can be used by many ISPs. - ISP has to install CGN to use ISP Shared Address. - ISP Shared Address must not be used at customers' site or Internet Exchanges. - Routing information of ISP Shared Address must not be advertised to the Internet. - Reverse DNS queries for this address space must not be sent to root DNS servers. - Packets with this space as source address and/or destination address must be filtered out at the border of each ISP. - It is known that almost every equipment such as routers, servers, and PCs reject packets from or to Class-E address [I-D.wilson-class-e]. Therefore, Class-E address is not applicable Shirasaki, et al. Expires May 3, 2009 [Page 3] Internet-Draft ISP Shared Address October 2008 as ISP Shared Address. - Addresses within this address space should be unique within the ISP, or the set of ISPs which choose to cooperate over this space so they may directly communicate with each other in their networks. 3. Size of Address Space The following table shows the coverage by the size of ISP Shared Address. This table shows that four blocks of /8 are required to cover all ISPs on the Earth. On the other hand, because, the minimum aggregation size of rural network is /12 in Japan (actually this happens around Tokyo area), we think /12 is the hard limit of minimum size ISP Shared Address. Therefore, we recommend to assign four /8 as the ISP Shared Address space but of cause we understand this can be determined by further discussions. +----------------------------+--------------+----------------+ | Size of ISP Shared Address | ISP Coverage | Number of ISPs | +----------------------------+--------------+----------------+ | /10 | 44% | 103 | | /9 | 52% | 58 | | /8 | 65% | 35 | | /8 x2 | 82% | 19 | | /8 x3 | 92% | 6 | | /8 x4 | 100% | 2 | +----------------------------+--------------+----------------+ ISP coverage is the ratio that ISPs are covered by the size of ISP Shared Address as of October in 2008. It is calculated with numbers of hosts in the IPv4 internet. Table was generated by observing actual BGP announcements. Table 1: Coverage by Size of ISP Shared Address 4. Acknowledgements Thanks for the input and review by Shirou Niinobe, Takeshi Tomochika, Tomohiro Fujisaki, Dai Nishino, JP address community members, AP address community members and JPNIC members. Shirasaki, et al. Expires May 3, 2009 [Page 4] Internet-Draft ISP Shared Address October 2008 5. IANA Considerations IANA is to record the allocation of the IPv4 global unicast address as ISP Shared Address in the IPv4 address registry. 6. Security Considerations ISP Shared Address is supposed to be used with CGN. The Global IPv4 address that is assigned outside CGN may be used as source address of 'Denial of Service' attack. 7. References 7.1. Normative References [I-D.nishitani-cgn] Nishitani, T. and S. Miyakawa, "Carrier Grade Network Address Translator (NAT) Behavioral Requirements for Unicast UDP, TCP and ICMP", draft-nishitani-cgn-00 (work in progress), July 2008. [I-D.shirasaki-nat444-isp-shared-addr] Shirasaki, Y., Ed., Miyakawa, S., Nakagawa, A., Yamaguchi, J., and H. Ashida, "NAT444 with ISP Shared Address", draft-shirasaki-nat444-isp-shared-addr-00 (work in progress), October 2008. [I-D.wilson-class-e] Wilson, P., Michaelson, G., and G. Huston, "Redesignation of 240/4 from "Future Use" to "Private Use"", draft-wilson-class-e-02 (work in progress), September 2008. 7.2. Informative References [PROP58] Niinobe, S., Tomochika, T., Yamaguchi, J., Nishino, D., Ashida, H., Nakagawa, A., and T. Hosaka, "Proposal to create IPv4 shared use address space among LIRs", 2008, . Shirasaki, et al. Expires May 3, 2009 [Page 5] Internet-Draft ISP Shared Address October 2008 Authors' Addresses Yasuhiro Shirasaki (editor) NTT Communications Corporation NTT Hibiya Bldg. 7F, 1-1-6 Uchisaiwai-cho, Chiyoda-ku Tokyo 100-8019 Japan Phone: +81 3 6700 8530 Email: yasuhiro@nttv6.jp Shin Miyakawa NTT Communications Corporation Tokyo Opera City Tower 21F, 3-20-2 Nishi-Shinjuku, Shinjuku-ku Tokyo 163-1421 Japan Phone: +81 3 6800 3262 Email: miyakawa@nttv6.jp Akira Nakagawa KDDI CORPORATION GARDEN AIR TOWER, 3-10-10, Iidabashi, Chiyoda-ku Tokyo 102-8460 Japan Email: ai-nakagawa@kddi.com Jiro Yamaguchi Internet Initiative Japan Inc. Jinbocho Mitsui Bldg., 1-105 Kanda Jinbo-cho, Chiyoda-ku Tokyo 101-0051 Japan Phone: +81 3 5205 6500 Email: jiro-y@iij.ad.jp Shirasaki, et al. Expires May 3, 2009 [Page 6] Internet-Draft ISP Shared Address October 2008 Hiroyuki Ashida its communications Inc. 3-5-7 Hisamoto Takatsu-ku Kawasaki-shi Kanagawa 213-0011 Japan Email: ashida@itscom.ad.jp Shirasaki, et al. Expires May 3, 2009 [Page 7] Internet-Draft ISP Shared Address October 2008 Full Copyright Statement Copyright (C) The IETF Trust (2008). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Shirasaki, et al. Expires May 3, 2009 [Page 8]