DMM D. Liu Internet-Draft China Mobile Intended status: Standards Track Octorber 14, 2012 Expires: April 17, 2013 Deployment of existing mobility protocols in DMM Scenario. draft-liu-dmm-of-deployment-00 Abstract Distributed Mobility Managment(DMM) aims to eliminate the centralized anchor point of current IP mobility solutions to get better scalability and optimize the data plane routing. Many soulutions have been proposed in DMM working group but before defining any new DMM protocol, it is a good approach to investigate first whether it is feasible to deploy current IP mobility protocol in DMM scenario in a way that can meet all the requirment of DMM.This document discusses the way of the deployment of current IP mobility protocol in DMM scenario and analyses the gaps between this approach and the DMM requirment. Requirements Language 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 [RFC2119]. 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 April 17, 2013. Copyright Notice Copyright (c) 2012 IETF Trust and the persons identified as the Liu Expires April 17, 2013 [Page 1] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Distributed Mobility Management Use Cases . . . . . . . . . . . 3 3. Deployment of current IP mobility protocol in DMM scenario . . 4 3.1. Client-based mobility solution in DMM scenario . . . . . . 4 3.2. Network based mobility solution in DMM scenario . . . . . . 5 4. Gap analysis . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 7. Co-authors and Contributors . . . . . . . . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 9.1. Normative References . . . . . . . . . . . . . . . . . . . 8 9.2. Informative References . . . . . . . . . . . . . . . . . . 8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 8 Liu Expires April 17, 2013 [Page 2] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 1. Introduction Most existing IP mobility solutions are derived from Mobile IP [RFC3775] principles where a given mobility anchor (e.g. the Home Agent (HA) in Mobile IP or the Local Mobility Agent (LMA) in Proxy Mobile IPv6 [RFC5213] maintains Mobile Nodes (MNs) bindings. Data traffic is then encapsulated between the MN or its Access Router (e.g. the Mobile Access Gateway (MAG) in PMIPv6) and its mobility agent. These approaches lead to the implementation of centralised architectures where both MN context and traffic encapsulation need to be maintained at a central network entity, the mobility anchor. Such centralised approach provides the ability to route MN traffic whatever MN's localisation while maintaining IP session continuity during handovers. However, when hundreds of thousands of MNs are communicating in a given cellular network, a centralized mobility anchoring point causes well-known bottlenecks and single point of failure issues, which requires costly network dimensioning and engineering to be fixed. In addition, tunnelling encapsulations impact the overall network efficiency since they require the maintenance of MN's specific contexts in each tunnel end nodes and they incur delays in packet processing and transport functions. 2. Distributed Mobility Management Use Cases Distribued Mobility Managment can be use in the following use cases: 1.Local break out scenario The fast increase of data traffic gives operators much presure on their core network, operators have to extend their core network capacity and thence increase the cost. To deal with this problem, operators tend to offload their traffic in the network edge to decrease the presure of their core network. This kind of solution usually called "local break out". In 3GPP, LIPA/SIPTO architecture is such kind of offload solutions for mobile operators. In the local break out scenario, the traffic is routed near the access point, but current IP mobility solution's anchor point usually located in the core network level. To solve this problem we can deploy the mobility anchor in the network edge, it will be discussed in detail in the following section. 2. CDN/Cache scenario Similar to the local break out scenario, CDN/Cache usually been deployed in the network edge. In this scenario if all the data traffic still need to go back to a centralized mobility anchor in the core network it will cancel out the effect of CDN/cache. So the Liu Expires April 17, 2013 [Page 3] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 solution is also to deploy the mobility anchor point near the access network. 3. Deployment of current IP mobility protocol in DMM scenario Current IP mobility protocol can be classified into client-based solution and network based solution. The basic idea is to deploy the mobility anchor near the access network and in this scenario, the MN may have more than one mobility anchors. 3.1. Client-based mobility solution in DMM scenario One solution to deploy Mobile IP in DMM scenario is to implement the HA functionalities in the access routers, as shown on Figure 1. Any given IP flow can be considered as implicitly anchored on the current host's access router when set up. In addition, dynamic mobility anchoring [I-D.kassi-mobileip-dmi] could avoid data encapsulation for motionless nodes: until the host does not move, the IP flow is delivered as for any standard IPv6 node. The anchoring function at the access router is acting only to manage traffic indirection while the host moves to a new access router. So, when the MN handoff, its current traffic is still attached to the anchor access router which is responsible for forwarding the IP flows to the MN.For example, let's consider an IP flow, flow#1, initiated by the mobile node, MN, when attached to AR2. Flow#1 will is routed in a standard way as long as the MN remain attached to AR2. If the MN moves to AR3, flow#1 remains anchored to AR2, which plays the role of HA. If MN starts a new IP communication, flow#2, while attached to AR3; flow#2 will be routed in a standard way as long as the MN remains attached to AR3. Then, if the MN moves to AR1, flow#1 and flow#2 will be respectively anchored to AR2/HA and AR3/HA. Liu Expires April 17, 2013 [Page 4] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 +---+ +---+ +---+ |CN1| |CN2| |CN3| +---+ +---+ +--,+ _.---------+----------. \ ,----'' | `---'-. ,-' |flow#1 \ `-. ,' | ' `. ( IP Network| \ `. | ' ,' `-. ; ,\' ;-----. ; _.----' ' ,' `---------+----------'' | / | ' +---'---+ +---:---+ +-------+ | AR1 | | AR2`--|------------| AR3 | | HA | | HA |------------|HA | +-------+ +-------+ +-------+ flow#1 \\ \ flow#2 tunnelled \\ ' +-----+ +--\--+ | MN | ----move-------> | MN | +-----+ +-----+ Distributed Client Based Mobility 3.2. Network based mobility solution in DMM scenario Figure 2 shows the deployment of PMIP [RFC5213] in DMM scenario. The basic is to distribute mobility traffic management with dynamic user's traffic anchoring in the access network nodes. Each AR supports both the MAG and LMA functionalities. Any given IP flow can be considered as implicitly anchored on the current host's access router when set up. Until the host does not move, the IP flow is delivered as for any standard IPv6 node. The anchoring function at the access router is thus acting only to manage traffic indirection while the host moves to a new access router. So, when the MN handoff, its current traffic is still attached to the anchor access router which is responsible for forwarding its anchored MN's IP flows to the new MN's location (i.e. to the AR the MN is attached to). For example, let's consider an IP flow, flow#1, initiated by the mobile node, MN, when attached to AR2. Flow#1 will is routed in a standard way as long as the MN remain attached to AR2. If the MN moves to AR3, flow#1 remains anchored to AR2, which plays the role of LMA. AR3 plays the role of MAG for MN/flow#1. If MN starts a new IP communication, flow#2, while attached to AR3; flow#2 will be routed in a standard way as long as the MN remains attached to AR3. Then, if the MN moves to AR1, flow#1 and flow#2 will be respectively anchored to AR2/LMA and AR3/LMA and AR1 will provide MAG Liu Expires April 17, 2013 [Page 5] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 functionalities for MN. +---+ +---+ +---+ |CN1| |CN2| |CN3| +---+ +---+ +--,+ _.---------+----------. \ ,----'' | `---+-. ,-' |flow#1 \ `-. ,' | \ `. ( IP Network| \ `. | \ ,' `-. ; ,+' ;-----. ; _.----' `. ,' `---------+----------'' | / | flow#1 \ +---'---+ +---:---+ tunnelled +-------+ | AR1 | | AR2`--|------------| AR3 | |MAG/LMA| |MAG/LMA|------------|MAG/LMA| +-------+ +-------+ +-------+ flow#1 `. \ flow#2 +--`--+ +-----+ | MN | ----move-------> | MN | +-----+ +-----+ Distributed Network Based Mobility 4. Gap analysis There are several problems need to consider in the above solutions. draft draft-liu-dmm-dynamic-anchor-discussion-00 , draft-liu-dmm-address-selection-00 and draft-liu-dmm-mobility-api-00 has discussed those problems in detail. 5. IANA Considerations This document makes no request of IANA. Note to RFC Editor: this section may be removed on publication as an RFC. 6. Security Considerations TBD Liu Expires April 17, 2013 [Page 6] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 7. Co-authors and Contributors Many content of this document comes from DMM barbof and draft-liu-distributed-mobility-02, the original authors was list here as co-authors and contributors: Pierrick Seite: pierrick.seite@orange-ftgroup.com Hidetoshi Yokota: yokota@kddilabs.jp Charles E. Perkins: charliep@computer.org Hui Deng: denghui@chinamobile.com Melia Telemaco: telemaco.melia@alcatel-lucent.com Elena Demaria: elena.demaria@telecomitalia.it Peter McCann: Peter.McCann@huawei.com Kostas Pentikousis: k.pentikousis@huawei.com Tricci So: tso@zteusa.com Jong-Hyouk Lee: jh.lee@telecom-bretagne.eu Jouni Korhonen: jouni.korhonen@nsn.com Sri Gundavelli: sgundave@cisco.com Carlos J. Bernardos: cjbc@it.uc3m.es Marco Liebsch: Marco.Liebsch@neclab.eu Wen Luo: luo.wen@zte.com.cn Georgios Karagiannis: g.karagiannis@utwente.nl Julien Laganier: jlaganier@juniper.net Wassim Michel Haddad: Wassam.Haddad@ericsson.com Alexandru Petrescu: alexandru.petrescu@gmail.com Seok Joo Koh: sjkoh@knu.ac.kr Dirk von Hugo: Dirk.von-Hugo@telekom.de Liu Expires April 17, 2013 [Page 7] Internet-Draft draft-liu-dmm-of-deployment-00 Oct. 2012 Ahmad Muhanna: amuhanna@awardsolutions.com 8. Acknowledgements TBD 9. References 9.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 9.2. Informative References [I-D.draft-seite-dmm-dma-00] Seite, P. and P. Bertin, "Distributed Mobility Anchoring, draft-seite-dmm-dma-00", February 2012. Author's Address Dapeng Liu China Mobile 32 Xuanwumen West Street Beijng, Xicheng District, 100053 China Phone: +86-13911788933 Email: liudapeng@chinamobile.com Liu Expires April 17, 2013 [Page 8]