Network Working Group C. Wan Internet-Draft C. Ye Expires: December 17, 2006 X. Qin Huawei Technologies June 15, 2006 Scenario analysis and problem statement of the dual-stack mobile entity roaming in the ipv4 and ipv6 network draft-wan-mip6-nemo-dsanalysis-00.txt 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 December 17, 2006. Copyright Notice Copyright (C) The Internet Society (2006). Abstract The purpose of this document is to investigate the motivations for mobile entities using dual stacks and the scenarios of mobile entities with dual-stacks roaming in the ipv4 or ipv6 network. This document also discusses the problems to be solved during these scenarios. Wan, et al. Expires December 17, 2006 [Page 1] Internet-Draft dual stack analysis June 2006 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Analysis of these scenarios . . . . . . . . . . . . . . . . . 12 5. New functions needed in the network . . . . . . . . . . . . . 13 6. Associated problems . . . . . . . . . . . . . . . . . . . . . 14 7. Security considerations . . . . . . . . . . . . . . . . . . . 15 8. IANA considerations . . . . . . . . . . . . . . . . . . . . . 16 9. Normative References . . . . . . . . . . . . . . . . . . . . . 16 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17 Intellectual Property and Copyright Statements . . . . . . . . . . 18 Wan, et al. Expires December 17, 2006 [Page 2] Internet-Draft dual stack analysis June 2006 1. Introduction The primary requirement of the mobile ip technology is to maintain the mobile entity's ip address during its movement. This is a network layer solution. Currently, there are two kinds of network layer technology (ipv4 and ipv6). Accordingly there are two protocols for mobile ip solution: mip4 and mip6. For a long time, ipv4 and ipv6 will exist simultaneously, so the mobile entity may roam into the ipv4 or ipv6 network during its movement. However mip4 protocol can only solve roaming problems in the ipv4-only network, and mip6 protocol can only solve roaming problems in the pure ipv6 network. To maintain communication in both ipv4 network and ipv6 network, analysis of dual-stack scenarios and problems is needed. Wan, et al. Expires December 17, 2006 [Page 3] Internet-Draft dual stack analysis June 2006 2. Terminology 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 BCP 14 [RFC2119]. Mobility related terminology is defined in [RFC3753]. Wan, et al. Expires December 17, 2006 [Page 4] Internet-Draft dual stack analysis June 2006 3. Scenarios Scenarios of mobile entity roaming in both ipv4 and ipv6 [RFC2460] network are comprised of entities and their attributes. Movement of a mobile entity in both ipv4 and ipv6 network relates to several network entities: Mobile entity (ME), Home agent (HA), Access router (AR), Correspondent node. Mobile entity (ME): the mobile entity may be a mobile node or a mobile router[RFC3963]. Its attributes are listed below: The attribute ipv4 stack means whether the mobile entity supports mip4 protocol[RFC3344]. The attribute ipv6 stack means whether the mobile entity supports mip6 protocol[RFC3775]. The attribute ipv4 home address means whether the mobile entity has ipv4 home address. The attribute ipv6 home address means whether the mobile entity has ipv6 home address. The attribute care-of address means the mobile entity's COA type, in ipv6 network the mobile entity can get a COA by configuration and in ipv4 network the mobile entity can get a co-COA or configured COA. To roam within heterogeneous networks, the mobile entity must have an ipv4 stack and an ipv6 stack and it must support both mip4 and mip6 protocols. If the mobile entity has only an ipv4 stack, then it can only roam in the ipv4 network, and it acts as a normal mip4 entity. If the mobile entity has only an ipv6 stack, then it can only roam in the ipv6 network, and it acts as a normal mip6 entity. Current protocol has solved the single stack problem, so in this paper, we assume that the mobile entity has both ipv4 and ipv6 stacks and supports both mip4 and mip6 protocols. After the mobile entity is booted up, it should have at least an ipv4 address or an ipv6 address. The mobile entity will get a care-of address, when it roams into a new network. If the new network is an ipv4 network, the care-of address may be a co-COA, and the access router will be a foreign agent to the mobile entity. Home agent (HA): in the mip6/mip4 protocol, the home agent will relay packets to the mobile node. Its attributes are listed below: The attribute ipv4 stack means whether the HA has ipv4 stack and supports mip4 protocol. The attribute ipv6 stack means whether the HA has ipv6 stack and supports mip6 protocol. The attribute ipv4 address means whether the HA has ipv4 address. The attribute ipv6 address means whether the HA has ipv6 address. The attribute IPv4 address pool means whether the HA support the assignment of IPv4 address for the mobile entity. The attribute IPv6 address pool means whether the HA support the assignment of IPv6 address for the mobile node. The home agent must have at least an ipv4 stack or an ipv6 stack, and must have at least an ipv4 service address or an ipv6 service address. The home agent Wan, et al. Expires December 17, 2006 [Page 5] Internet-Draft dual stack analysis June 2006 may have an ipv4 address pool or an ipv6 address pool. Access router (AR): the mobile entity will access the network through the access router, and the access router may help the mobile entity in communication. The access router may be a foreign agent in the mip4 or a router of any kind. Its attributes are listed below: The attribute ipv4 stack means whether the access router has ipv4 stack and supports mip4 protocol. The attribute ipv6 stack means whether the access router has ipv6 stack and supports mip6 protocol. The attribute ipv4 address means whether the access router has ipv4 address. The attribute ipv6 address means whether the access router has ipv6 address. The access router should have at least a ipv4 or ipv6 stack, thus it should have an ipv4 or ipv6 address, if it is an ipv4 access router, it may give the mobile entity a co-COA. Correspondent node (CN): a node that communicates with the mobile entity. If the mobile entity communicates with the CN with its ipv4 address, then the CN's address must be an ipv4 address from mobile entity's perspective. If the mobile entity communicates with the CN with its ipv6 address, then the CN's address must be an ipv6 address from mobile entity's perspective. Usually, the dual-stack scenario will not affect the correspondent node, if the mobile entity uses the route optimization method while communicating with the correspondent node, the correspondent may act as the home agent during BU. With the analysis of entities and their attributes, we can define the dual-stack scenarios. We assume that the mobile entity has dual- stacks and supports both mip4 and mip6 protocols. If the correspondent node supports route optimization method, the attribute requirements of CN are similar to home agent. So we don't consider the correspondent node in these scenarios. Scenario 1: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 home address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has an ipv4 co-COA. Scenario 2: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. Scenario 3: The mobile entity has dual-stack and supports both mip4 Wan, et al. Expires December 17, 2006 [Page 6] Internet-Draft dual stack analysis June 2006 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only an ipv6 address, the access router has only ipv6 stack and ipv6 address. This scenario can be solved by current mip6 protocol. Scenario 4: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only an ipv6 address, the access router has ipv6/ ipv4 stack and ipv6/ipv4 address. Current mip6 protocol can solve this problem. Scenario 5: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. Scenario 6: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. Scenario 7: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv6 stack and ipv6 address. This scenario can be solved by current mip6 protocol. Scenario 8: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has both ipv6 address and ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ipv4 address. This scenario can be solved by current mip6 protocol. Scenario 9: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. This scenario will not exist. Scenario 10: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. This scenario will not exist. Scenario 11: The mobile entity has dual-stack and supports both mip4 Wan, et al. Expires December 17, 2006 [Page 7] Internet-Draft dual stack analysis June 2006 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only ipv4 address, the access router has only ipv6 stack and ipv6 address. Currently, we do not consider this scenario because this scenario will not exist. Scenario 12: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv6 home address, but it has no ipv4 address, its home agent has only ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ipv4 address. Currently, we do not consider this scenario because this scenario will not exist. Scenario 13: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. Currently, we do not consider this scenario because this scenario will not exist. Scenario 14: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. Currently, we do not consider this scenario because this scenario will not exist. Scenario 15: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only an ipv6 address, the access router has only ipv6 stack and ipv6 address. Currently, we do not consider this scenario because this scenario will not exist. Scenario 16: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only an ipv6 address, the access router has ipv6/ ipv4 stack and ipv6/ipv4 address. Currently, we do not consider this scenario because this scenario will not exist. Scenario 17: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. This scenario can be solved by mip4 protocol. Scenario 18: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. This scenario can be solved by mip4 protocol. Wan, et al. Expires December 17, 2006 [Page 8] Internet-Draft dual stack analysis June 2006 Scenario 19: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv6 stack and ipv6 address. Scenario 20: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has both ipv6 address and ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ipv4 address. This scenario can be solved by current mip4 protocol. Scenario 21: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. This scenario can be solved by current mip4 protocol. Scenario 22: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. This scenario can be solved by current mip4 protocol. Scenario 23: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only ipv4 address, the access router has only ipv6 stack and ipv6 address. Scenario 24: The mobile entity has dual-stack and supports both mip4 and mip6, it has an ipv4 home address, but it has no ipv6 address, its home agent has only ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ipv4 address. This scenario can be solved by current mip4 protocol. Scenario 25: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. This scenario will not exist, so we do not consider it. Scenario 26: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only an ipv6 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. This scenario will not exist, so we do not consider it. Scenario 27: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has Wan, et al. Expires December 17, 2006 [Page 9] Internet-Draft dual stack analysis June 2006 only an ipv6 address, the access router has only ipv6 stack and ipv6 address. This scenario will not exist, so we do not consider it. Scenario 28: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only an ipv6 address, the access router has ipv6/ipv4 stack and ipv6/ ipv4 address. This scenario will not exist, so we do not consider it. Scenario 29: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. Scenario 30: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has both ipv6 address and ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. Scenario 31: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home addresses, its home agent has both ipv6 address and ipv4 address, the access router has only ipv6 stack and ipv6 address. Scenario 32: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has both ipv6 address and ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ipv4 address. Scenario 33: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a co-COA. This scenario will not exist, so we do not consider it. Scenario 34: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only ipv4 address, the access router has only ipv4 stack and ipv4 address. The mobile entity has a configured COA. This scenario will not exist, so we do not consider it. Scenario 35: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has only ipv4 address, the access router has only ipv6 stack and ipv6 address. This scenario will not exist, so we do not consider it. Scenario 36: The mobile entity has dual-stack and supports both mip4 and mip6, it has both ipv4 and ipv6 home address, its home agent has Wan, et al. Expires December 17, 2006 [Page 10] Internet-Draft dual stack analysis June 2006 only ipv4 address, the access router has ipv6/ipv4 stack and ipv6/ ipv4 address. This scenario will not exist, so we do not consider it. Wan, et al. Expires December 17, 2006 [Page 11] Internet-Draft dual stack analysis June 2006 4. Analysis of these scenarios If the visited network is an ipv4/ipv6 mixed network, current mip4 and mip6 protocols are enough to solve the problems, so we assume that the visited network is an ipv4 or ipv6 only network. Based on this assumption, these scenarios can be divided into three categories In the first category, the home network is an ipv4/ipv6 mixed network[DSMIP]. The dual-stack mobile entity with at least an ipv6 address roams in the ipv4 or ipv6 network. In the second category, the dual-stack mobile entity with an ipv6 home address roams in the ipv4 network. The home network is an ipv6 only network. In the third category, the dual-stack mobile entity with an ipv4 home address roams in the ipv6 network. The home network is an ipv4 only network As the ipv4 and ipv6 protocol will exist simultaneously for a long time, the three categories of scenarios are all reasonable. Wan, et al. Expires December 17, 2006 [Page 12] Internet-Draft dual stack analysis June 2006 5. New functions needed in the network In the first category, the mobile entity can communicate with the home agent by ipv4 or ipv6 protocol, no new facility is needed. In the second category, the mobile entity needs to send its ipv6 binding update to the home agent or the correspondent node from an ipv4 only network. In the third category, the mobile entity needs to send its ipv4 binding update to the home agent from an ipv6 only network. In these scenarios, mobile entity can not communicate with its home agent directly. The communication between mobile entity and its home agent depends on other network facility. Currently, there are two kinds of technologies in the ipv6/ipv4 interconnection field: NAT/PT and tunnel. There are many tunneling technologies for communicating between ipv4 and ipv6 network. Surely, we can use these technologies to deal with these scenarios. There are some other solutions that rely on mip4 and mip6 protocols. Some of these solutions may need new facility in the network. For example, to solve the problems involved in the second and third category scenarios, a network facility that supports both mip4 and mip6 protocol is needed and a solution based on current mip4 and mip6 protocols is needed. Wan, et al. Expires December 17, 2006 [Page 13] Internet-Draft dual stack analysis June 2006 6. Associated problems When the mobile entity with an ipv6-only home network roams into a visited network which runs ipv4-only protocol, it can not use mip6 protocol without tunneling or other support, and it may need new facility to tunnel packet from ipv4 network into ipv6 network. When the mobile entity with an ipv4-only home network roams into the ipv6- only network, it can not use mip4 protocol without tunneling or other support, and it may need new facility to tunnel packet from ipv6 network into ipv4 network too. In these scenarios, facility discovery, routing mechanism, and binding update mechanism are all needed. If the mobile entity boots up in the visited network which runs a different ip protocol with its home network, current bootstrapping technology does not work any more[BOOT]. New protocol is needed. When the mobile entity roams from one network into another network which runs a different ip protocol, hand over perfermance is very important. And the Fmip6 protocol needs to be extended. To improve hand over perfermance, MIH system may need to consider these scenarios. As the home network and visited network maybe run different AAA protocols, it is a problem of mobile entity to get access service. At the same time, the access security may be different from the home network. How to ensure the access security is a problem too. These problems are noncommittal now. Wan, et al. Expires December 17, 2006 [Page 14] Internet-Draft dual stack analysis June 2006 7. Security considerations The security consideration is mentioned in the section associated problems. Wan, et al. Expires December 17, 2006 [Page 15] Internet-Draft dual stack analysis June 2006 8. IANA considerations The document requires nothing from IANA. 9. Normative References [BOOT] "Mobile IPv6 bootstrapping in split scenario", , June 2005. [DSMIP] "Mobile IPv6 support for dual stack Hosts and Routers (DSMIPv6)", , March 2006. [RFC2119] "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, October 1997. [RFC2460] "Internet Protocol version 6 (IPv6) specification", RFC 2460. [RFC3344] "Mobility Support for IPv4", RFC 3344. [RFC3753] "Mobility Related Terminology", RFC 3753, June 2004. [RFC3775] "Mobility Support in IPv6", RFC 3775, June 2004. [RFC3963] "Network Mobility (NEMO) Basic Support protocol", RFC 3963, January 2005. Wan, et al. Expires December 17, 2006 [Page 16] Internet-Draft dual stack analysis June 2006 Authors' Addresses Changsheng Wan Huawei Technologies Site A,Floor 10,HuiHong Mansion,No.91 BaiXia Rd. Nanjing, China 210001 Phone: +86-25-84565415 Email: wanchangsheng@huawei.com Chengping Ye Huawei Technologies Site A,Floor 10,HuiHong Mansion,No.91 BaiXia Rd. Nanjing, China 210001 Phone: +86-25-84565414 Email: yechengping@huawei.com Xia Qin Huawei Technologies Site A,Floor 10,HuiHong Mansion,No.91 BaiXia Rd. Nanjing, China 210001 Phone: +86-25-84565414 Email: alice.Q@huawei.com Wan, et al. Expires December 17, 2006 [Page 17] Internet-Draft dual stack analysis June 2006 Intellectual Property Statement 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. Disclaimer of Validity 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 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. Copyright Statement Copyright (C) The Internet Society (2006). 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. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Wan, et al. Expires December 17, 2006 [Page 18]