netext X. Zhou Internet-Draft ZTE Corporation Intended status: Standards Track January 28, 2011 Expires: August 1, 2011 Prefix Delegation for Proxy Mobile IPv6 draft-zhou-netext-pd-pmip-00.txt Abstract This document attempts to explain how proxy mobile IPv6 supports prefix delegation. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on August 1, 2011. Copyright Notice Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November Zhou Expires August 1, 2011 [Page 1] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Protocol Overview . . . . . . . . . . . . . . . . . . . . . . 4 2.1. DHCPv6 Relay Agent Co-located with the MAG . . . . . . . . 4 2.2. DHCPv6 Server Co-located with the MAG . . . . . . . . . . 6 3. Mobility Option . . . . . . . . . . . . . . . . . . . . . . . 9 3.1. Delegated Prefix Notify Option . . . . . . . . . . . . . . 9 3.2. Delegated Prefix Reply Option . . . . . . . . . . . . . . 10 4. Local Mobility Anchor Operation . . . . . . . . . . . . . . . 12 4.1. Processing Proxy Binding Update . . . . . . . . . . . . . 12 4.2. Forwarding Considerations . . . . . . . . . . . . . . . . 12 5. Mobile Access Gateway Operation . . . . . . . . . . . . . . . 13 5.1. Forwarding Considerations . . . . . . . . . . . . . . . . 13 6. Security Considerations . . . . . . . . . . . . . . . . . . . 14 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 8. Normative References . . . . . . . . . . . . . . . . . . . . . 16 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 17 Zhou Expires August 1, 2011 [Page 2] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 1. Introduction DHCPv6 prefix delegation rfc3633 (DHCPv6PD) can be used to assign a prefix or prefix(es) to a Mobile Router. If a MR is provided Proxy Mobile IPv6 Protocol as its mobility management when connecting the network, currently neither the MAG nor the LMA can be able to identify the packet including delegated prefix(es). When the MR (Requesting Router) uses DHCPv6PD to obtain the delegated prefix(es), these prefix(es) SHOULD be associated with the PMIP binding, or the relevant packets may be discarded by the MAG or the LMA. This document describes extension to PMIP for supporting prefix delegation. Zhou Expires August 1, 2011 [Page 3] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 2. Protocol Overview Two DHCPv6 prefix delegation deployment configurations are as following o DHCPv6 relay agent co-located with the mobile access gateway. o DHCPv6 server co-located with the mobile access gateway. The MN (requesting router) MUST obtain the home network prefix before initiating the DHCPv6 prefix delegation procedure. 2.1. DHCPv6 Relay Agent Co-located with the MAG This section gives explanation on protocol operation in the case of DHCPv6 relay agent being located in the MAG. In this scenario, the procedure of DHCPv6 prefix delegation is transparent to the LMA. Upon receiving the DHCPv6 REPLY message from the delegating router the MAG SHOULD explicitly notify the LMA that the delegated prefix(es) need to be associated with current binding via sending a Proxy Binding Update message. Zhou Expires August 1, 2011 [Page 4] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 +-------------------+ +------------------+ +--------+ +------------+ | MN | | MAG | | LMA | | Delegating | |(Requesting Router)| |(DHCP Relay Agent)| +--------+ | Router | +-------------------+ +------------------+ | +------------+ | | | | | |---------------------| | | | 1.PMIP tunnel | | | |---------------------| | |--2.DHCPv6 SOLICIT-->| | | | |---------2.DHCPv6 SOLICIT---------->| | |<--------3.DHCPv6 ADVERTIZE---------| | | | | |<-3.DHCPv6 ADVERTIZE-| | | | | | | |--4.DHCPv6 REQUEST-->| | | | |--4.DHCPv6 REQUEST----------------->| | | | | | |<-----5.DHCPv6 REPLAY---------------| | | | | | |--------6.PBU------->| | | | | | | |<-------7.PBA--------| | | | | | |<--8.DHCPv6 REPLY----| | | | | | | | | | | Figure 1: Case of DHCPv6 relay located at MAG for PMIP supporting prefix delegation The steps of the procedure in Figure 1 are as following. 1. The PMIPv6 tunnel is set up between the MAG and LMA. The MAG plays function of DHCPv6 relay agent between the MN and the DHCPv6 server. 2. The MN which acts as a !oRequesting Router!+/- as described in rfc3633 sends DHCPv6 SOLICIT massage including one or more IA_PD option(s) to the MAG to acquire the delegated prefix(es). The DHCPv6 relay agent on the MAG as described in rfc3315 relays the DHCPv6 SOLICIT message to the delegation router. The LMA can be aware of the DHCPv6 message which is transported through the LMA. 3. The delegating router inserts one or more IA_PD option(s) including the delegated prefix(es) and send it to the MAG (DHCPv6 relay agent) via the DHCPv6 ADVERTIZE message. The MAG relays the DHCPv6 ADVERTIZE message to the MN. Zhou Expires August 1, 2011 [Page 5] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 4. The MN sends DHCPv6 REQUEST message with the IA_PD option(s) received from previous message to the MAG (DHCPv6 relay agent). The MAG relays the DHCPv6 REQUEST message to the delegating router. The delegating router responses the REQUEST to the MAG via DHCPv6 REPLY message. 5. Upon receiving the DHCPv6 REPLY message, the MAG notifies the delegated prefix(es) to the LMA by sending Proxy Binding Update message. A new mobility option, the Delegated Prefix Notify Option, is defined to include the delegated prefix(es), see section 3.1. 6. On reception of the PBU containing the Delegated Prefix Notify Option the LMA SHOULD add the delegated prefix(es) into the Binding Cache and include the Delegated Prefix Reply Option which is a new mobility option (see section 3.2) in the Proxy Binding Acknowledgement message to confirm binding of the delegated prefix(es). 7. After receiving the Proxy Binding Acknowledgement message the MAG SHOULD add the delegated prefix(es) into the Binding Update List locally. The MAG SHOULD not relay the DHCPv6 REPLY message to the MN until receiving the Proxy Binding Acknowledgement from the LMA. 8. The MN receives one or more IA_PD prefix(es) in the DHCPv6 REPLY message from the MAG. 2.2. DHCPv6 Server Co-located with the MAG This section explains how PMIPv6 support DHCPv6 prefix delegation in the deployment of delegating router located at the mobile access gateway, see Figure 3. Zhou Expires August 1, 2011 [Page 6] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 +-------------------+ +-------------------+ +-------+ | MN | | MAG | | LMA | |(Requesting Router)| |(Delegating Router)| +-------+ +-------------------+ +-------------------+ | | | | | |------------------| | | 1.PMIP tunnel | | |------------------| |---2.DHCPv6 SOLICIT-->| | | | | |<--3.DHCPv6 ADVERTIZE-| | | | | |---4.DHCPv6 REQUEST-->| | | | | | |------5.PBU------>| | | | | |<-----6.PBA-------| | | | |<--7.DHCPv6 REPLY-----| | | | | | | | Figure 2: DHCPv6 server located at MAG for PMIP supporting prefix delegation The steps of the procedure in Figure 2 are as following. 1. The PMIPv6 tunnel is set up between the MAG and LMA. The MAG plays function of delegating router. 2. The MN which acts as a !oRequesting Router!+/- as described in rfc3633 sends DHCPv6 SOLICIT massage including one or more IA_PD option(s) to the MAG which acts as a !oDelegating Router!+/- to acquire the delegated prefix(es). 3. The Delegating Router on the MAG as described in rfc3633 inserts one or more IA_PD option(s) including the delegated prefix(es) and send it to the MN via the DHCPv6 ADVERTIZE message. 4. The MN sends DHCPv6 REQUEST message to the MAG with the IA_PD option(s) received from previous message. 5. Before sending the DHCPv6 REPLY message to the MN the MAG SHOULD send the Proxy Binding Update message to the LMA to notify the association between the delegated prefix(es) and the binding. A new mobility option, the Delegated Prefix Option, is defined to contain the delegated prefix(es) in the PBU, see section 3.1. Zhou Expires August 1, 2011 [Page 7] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 6. On reception of the PBU containing the Delegated Prefix Option the LMA SHOULD add the delegated prefix(es) into the Binding Cache and insert a Delegated Prefix Reply Option which is a new option defined in section 3.2 into the Proxy Binding Acknowledgement message to confirm binding of the delegated prefix(es). After receiving the Proxy Binding Acknowledgement message the MAG SHOULD add the delegated prefix(es) into the Binding Update List locally. The MAG SHOULD not send the DHCPv6 REPLY message to the MN until receiving the Proxy Binding Acknowledgement from the LMA. 7. The MN receives one or more IA_PD prefix(es) in the DHCPv6 REPLY message from the MAG. Zhou Expires August 1, 2011 [Page 8] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 3. Mobility Option 3.1. Delegated Prefix Notify Option A new mobility option, Delegated Prefix Notify Option, is defined for use in the Proxy Binding Update sent by the MAG to the LMA. This option can be used to notify the LMA the delegated prefix(es) assigned to the MN. If there are more than one delegated prefix needing to be associated with the binding, more than one options are included in the Proxy Binding Update message. The Delegated Prefix Notify Option has an alignment requirement of 8n+4. Its format is as follows: 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | Prefix Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Delegated Prefix + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: Delegated Prefix Notify Option Type Assigned by the IANA Length 8-bit unsigned integer indicates the length of the option in octets, excluding the type and length fields. This field MUST be set to 18. Reserved (R) This 8-bit field is unused for now. The value MUST be initialized to 0 by the sender and MUST be ignored by the receiver. Prefix Length 8-bit unsigned integer indicating the prefix length of the delegated prefix contained in the option. Zhou Expires August 1, 2011 [Page 9] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 Delegated Prefix A 128-bit field containing the mobile node's Delegated Prefix. 3.2. Delegated Prefix Reply Option A new mobility option, Delegated Prefix Reply Option, is used to notify the MAG of confirmation of delegated prefix(es). The Delegated Prefix Reply Option has an alignment requirement of 8n+4. Its format is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Status | Prefix Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Delegated Prefix + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: Delegated Prefix Reply Option Type Assigned by the IANA Length 8-bit unsigned integer indicates the length of the option in octets, excluding the type and length fields. This field MUST be set to 18. Status Indicates success or failure for associating the delegated prefix with the binding. Values from 0 to 127 indicate success. Higher values (128 to 255) indicate failure. Prefix Length 8-bit unsigned integer the value is copied from the corresponding field of the Delegated Prefix Reply Option. Zhou Expires August 1, 2011 [Page 10] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 Delegated Prefix A 128-bit field which contains the mobile node's Delegated Prefix copied from the Delegated Prefix Notify Option. Zhou Expires August 1, 2011 [Page 11] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 4. Local Mobility Anchor Operation 4.1. Processing Proxy Binding Update All the considerations from Section 5.3.1 of rfc5213 MUST be applied on the encapsulated Proxy Binding Update message. Upon receiving the Proxy Binding Update message containing Delegated Prefix Notify Option, the local mobility anchor MUST add the delegated prefix(es) in its binding cache. The local mobility anchor MUST send the Proxy Binding Acknowledgement message with the Status field value set to 0. The message MUST be constructed as specified in Section x.x.x. 4.2. Forwarding Considerations Once the local mobility anchor receives the packet from the corresponding node whose destination IPv6 address belonging to the delegated prefix, the local mobility anchor SHOULD treat the packet as treating the ones with home network prefix. The local mobility SHOULD encapsulate the packet and send it to the mobile access gateway through the PMIPv6 bi-directional tunnel. Zhou Expires August 1, 2011 [Page 12] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 5. Mobile Access Gateway Operation 5.1. Forwarding Considerations Once the mobile access gateway receives an IPv6 packet whose destination IPv6 address belonging to the delegated prefix from the mobile node, the mobile access gateway SHOULD encapsulate the packet and send it to the local mobility anchor through the PMIPv6 bi- directional tunnel. Zhou Expires August 1, 2011 [Page 13] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 6. Security Considerations TBD Zhou Expires August 1, 2011 [Page 14] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 7. IANA Considerations TBD Zhou Expires August 1, 2011 [Page 15] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 8. Normative References [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. [RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6", RFC 3633, December 2003. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. Zhou Expires August 1, 2011 [Page 16] Internet-Draft Prefix Delegation for Proxy Mobile IPv6 January 2011 Author's Address Xingyue Zhou ZTE Corporation No.68 Zijinghua Rd,Yuhuatai District Nanjing China Phone: +86-25-5287-2129 Email: zhou.xingyue@zte.com.cn Zhou Expires August 1, 2011 [Page 17]