Network Working Group Zhengming. Ma Internet-Draft Lin. Wang Intended status: Informational SUN YAT-SEN UNIVERSITY Expires: June 16, 2012 December 14, 2011 Prefix Delegation for Hierarchy Mobile IPv6 draft-ma-netext-pdhmip-00.txt Abstract This document explains how network mobility and DHCPv6-based Prefix Delegation works with hierarchy mobile IPv6. It is an extension of HMIPv6 and allows a mobile network to attach to a MAP via a mobile router. It also makes use of the mechanism of DHCPv6PD to assign mobile network prefix (es) to the mobile router which plays the role of requesting router. 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 June 16, 2012. 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 Ma & Wang Expires June 16, 2012 [Page 1] Internet-Draft PDHMIP December 2011 described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. NEMO protocol for hierarchical mobile networks . . . . . . . . 4 3.1. Assumption . . . . . . . . . . . . . . . . . . . . . . . . 4 3.2. Set Up a tunnel . . . . . . . . . . . . . . . . . . . . . . 4 4. DHCPv6 Prefix Delegation for hierarchy mobile IPv6 . . . . . . 4 4.1. Assumption . . . . . . . . . . . . . . . . . . . . . . . . 5 4.2. Transmission of DHCPv6 Messages . . . . . . . . . . . . . . 5 4.3. Binding association with the delegated prefix . . . . . . . 5 4.4. Mobile Anchor Point Forward . . . . . . . . . . . . . . . . 7 4.4.1. Intercepting packets sent to the mobile router's mobile network prefix . . . . . . . . . . . . . . . . . 7 4.4.2. Forward packets to the mobile router . . . . . . . . . 7 4.5. Handover . . . . . . . . . . . . . . . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8 7. Normative References . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8 Ma & Wang Expires June 16, 2012 [Page 2] Internet-Draft PDHMIP December 2011 1. Introduction This document describes protocol extensions to HMIPv6 to enable support for network mobility. The extensions ensure session continuity for all the nodes in the mobile network, even as the mobile router changes its point of attachment to the MAP. The solution described in the document proposes a bi-directional tunnel between the Mobile Router and its Mobile Anchor Point. It also uses DHCPv6 prefix delegation to assign mobile network prefix (es) to a Mobile Router as specified in DHCPv6 Prefix Delegation for NEMO. The DHCPv6 server running at the MAP is provisioned with prefixes to be assigned using any of the prefix assignment mechanisms described in the DHCPv6PD specification [RFC3933] 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 [RFC2119]. The following terms used in this document are defined in the Mobile IPv6 specification [RFC6275]: Home Agent (HA) Home address (HoA) The following terms used in this document are defined in the Hierarchical Mobile IPv6 (HMIPv6) Mobility Management [RFC5380]: Access Router (AR) Mobility Anchor Point (MAP) HMIPv6-Aware Mobile Node On-Link Care-of Address (LCoA) Local Binding Update (LBU) Local Binding Acknowledgement (LBA) The following terms used in this document are defined in the Mobile Network terminology document [RFC4885]: Mobile Router (MR) Ma & Wang Expires June 16, 2012 [Page 3] Internet-Draft PDHMIP December 2011 Mobile Network (NEMO) Mobile Network Prefix (MNP) The following terms used in this documents are defined in the DHCPv6 [RFC3115] and DHCPv6 prefix delegation [RFC3633]specifications: Delegation Router (DR; acts as a DHCPv6 server) Requesting Router (RR; acts as a DHCPv6 client) DHCPv6 Relay Agent (DRA) DHCPv6 Prefix Delegation (DHCPv6PD) 3. NEMO protocol for hierarchical mobile networks With the network mobility basic support protocol [RFC3963], a mobile network can only be accessed via specific gateways called Mobile Routers. The Mobile Router is also the default gateway for the Mobile Network. A Mobile Router has a unique Home Address through which it is reachable when it is registered with its Home Agent. 3.1. Assumption In order to use the NEMO protocol for hierarchical mobile networks, this specification assumes a mobile network can be accessed via a mobile router which is a hmipv6-aware mobile router and should receive and process the MAP option and also be able to send local binding updates to the MAP. 3.2. Set Up a tunnel The network mobility service of a mobile router is managed by the mobile node's policy profile defined in [RFC5380]. The mobile router gets a LCoA and a RCoA during the mobile router initial attachment procedure. Then the mobile router sends LBU message to the MAP which will then reply a LBA message to the mobile router. The bi- directional tunnel is set up between the mobile router and the MAP. The LCoA and RCoA is stored in the binding cache of MAP. 4. DHCPv6 Prefix Delegation for hierarchy mobile IPv6 IPv6 Prefix Option for (DHCPv6) [RFC3633] extends the DHCPv6 [RFC3315] to support a mechanism for automated delegation of IPv6 prefixes. This mechanism is intended for delegating a long-lived Ma & Wang Expires June 16, 2012 [Page 4] Internet-Draft PDHMIP December 2011 prefix from a delegating router to a requesting router. 4.1. Assumption In order to use DHCPv6PD for hierarchical mobile networks, this specification also has following assumptions. o The MAP assumes the role of the delegating router which is configured with a set of prefixes to be used for assignment to customers at the time of each customer's first connection to the ISP service. o The MR assumes the role of the requesting router and the role of a DHCPv6 relay agent co-located with the requesting router function. 4.2. Transmission of DHCPv6 Messages The MAP (DR) and the mobile router (RR and DRA) exchange DHCPv6PD protocol messages as specified in [RFC3633]. 4.3. Binding association with the delegated prefix The MAP (DR) and the mobile router (RR) exchange DHCPv6PD protocol messages as specified in [RFC3633]. Ma & Wang Expires June 16, 2012 [Page 5] Internet-Draft PDHMIP December 2011 ----------------------------- -------- | MR | | MAP | | (RR) (DRA) | | (DR) | ---------------------------- -------- | | 1.Lcoal Binding Update | | |------------------------>| | | (LCoA, RCoA) | | | | | | 2.Lcoal Binding Ack | | |<------------------------| | | | |3.DHCPv6 Solicit | DHCPv6 Solicit | |..................>|--=====================->| | | | | DHCPv6 Advertise | 4.DHCPv6 Advertise | |<..................|<-=====================--| | | | |5.DHCPv6 Request | DHCPv6 Request | |..................>|--=====================->| | | | | DHCPv6 Reply | 6. DHCPv6 Reply | |<..................|<-=====================--| | | (Mobile Network Prefix) | | | | Figure 1: Prefix Delegation in HMIPv6 The steps of the procedure in Figure 1 are as following. 1. The MR sends a local binding update to the MAP in order to establish a binding between the RCoA and LCoA. 2. MAP replies a local binding acknowledgement to MR, and the HMIPv6 tunnel is set up between the MR and MAP. 3. The mobile router which acts as a "Requesting Router" as described in [RFC3633] sends DHCPv6 SOLICIT massage including one or more IA_PD option(s) to the MAP to acquire the delegated prefix(es). 4. Upon receiving DHCPv6 SOLICIT the MAP inserts one or more IA_PD option(s) including the delegated prefix(es) and send it to the MR (DHCPv6 relay agent) via the DHCPv6 ADVERTISE message. 5. The MR sends DHCPv6 REQUEST message with the IA_PD option(s) received from previous message to the MAP (DHCPv6 relay agent). 6. The delegating router responses the REQUEST to the MR via DHCPv6 REPLY message. The MAP adds an entry in its binding cache including Ma & Wang Expires June 16, 2012 [Page 6] Internet-Draft PDHMIP December 2011 the delegated prefixes and LCoA. 4.4. Mobile Anchor Point Forward 4.4.1. Intercepting packets sent to the mobile router's mobile network prefix When the MAP is serving to the mobile router, it MUST be able to receive packets those are sent to the mobile router!_s mobile network. In order to receive those packets, the MAP MUST adversative a connected router into the Routing Infrastructure for the mobile router!_s mobile network. 4.4.2. Forward packets to the mobile router On receiving a packet from a correspondent node with the destination address matching the mobile router!_s mobile network prefix (es) the MAP MUST forward the packet through the bi-directional tunnel set up for that mobile router. 4.5. Handover When the MR moves from the previously AR to a newly AR which is also in the domain of the same MAPGBP[not]the MR gets a new LCoA and needs to verify that the delegated Prefix (es) is available. The MR sends DHCPv6 Renew message to extend the lifetime of the delegated prefix. If the MR finds that the lifetime of the delegated prefix which is stored in the IA_PD Prefix Option carried by the DHCPv6 reply messages set to zero, the MR should triggers a DHCPv6 SOLICIT to MAP to acquire new delegated prefix(es). The MAP, once the DHCPv6 signaling has been completed, MUST add an entry in its binding cache including the delegated prefix(es) and LCoA. When the MR moves from the previously MAP to a newly MAP, MR will register with the new MAP, and register its new RCoA with its HA by sending a BU that specifies the binding (RCoA, home address), as in Mobile IPv6. In additional, MR should request the delegated prefix(es) from the Delegated Router at the MAP. 5. Security Considerations All security considerations from the Hierarchical Mobile IPv6 (HMIPv6) Mobility Management [RFC5380], DHCPv6 Prefix Delegation specification [RFC3633] apply when using the extensions defined in this document Ma & Wang Expires June 16, 2012 [Page 7] Internet-Draft PDHMIP December 2011 6. IANA Considerations This document reuses the mobile network prefix option defined in [RFC 3963] in hierarchy mobile IPv6 to assgin the mobile network prefix via DHCPv6 for prefix delegation. It does not introduce any additional IANA considerations 7. Normative References [RFC5380] Soliman, H., Castelluccia, C., ElMalki, K. and L. Bellier, "Hierarchical Mobile IPv6 (HMIPv6) Mobility Management", RFC 5380, October 2008. [RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6", RFC 3633, December 2003. [RFC6276] Droms, R. ,Thubert, P., Dupont, F., Haddad, W. and C. Bernardos, "DHCPv6 Prefix Delegation for Network Mobility (NEMO)", RFC 6276, July 2011. [RFC6275] Perkins, C., Johnson, D. and J. Arkko, "Mobility Support in IPv6", RFC 6275, July 2011. [RFC3963] Devarapalli, V., Wakikawa, R., Petrescu, A., and P. Thubert, "Network Mobility (NEMO) Basic Support Protocol", RFC 3963, January 2005. [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 Droms, R., "IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6", RFC3633, December 2003. Authors' Addresses Zhengming Ma SUN YAT-SEN UNIVERSITY GuangZhou, Higher Mega Center 510006 China Email: issmzm@mail.sysu.edu.cn Ma & Wang Expires June 16, 2012 [Page 8] Internet-Draft PDHMIP December 2011 Lin Wang SUN YAT-SEN UNIVERSITY GuangZhou, Higher Mega Center 510006 China Email: darling135603@163.com Ma & Wang Expires June 16, 2012 [Page 9]