INTERNET-DRAFT Haisheng Jiang Intended Status: Proposed Standard Huawei Expires: July 1, 2012 December 29, 2011 Load sharing support for MAGs in Proxy Mobile IPv6 draft-jiang-netext-ls-pmip-00 Abstract Proxy Mobile IPv6 (PMIPv6) is standardized by IETF to supply mobility management for mobile nodes (MN) in a local small area. When the numbers of MNs which attaching to the same MAG is very large, it will cause the problem that the arrival rate of data traffic is far surpass the process capacity of the MAG. So the MAG will suffer from process bottleneck. The IETF is working on optimization for PMIPv6. This document proposes a load sharing solution for MAGs by migrating the Picked Mobile Node (PMN) to some MAGs without overload to sharing the traffic load, which can relieve stress of the overloaded MAG and improve the performance of PMIPv6 network. Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Copyright and License Notice Copyright (c) 2011 IETF Trust and the persons identified as the Haisheng Jiang Expires July 1, 2012 [Page 1] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 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. Requirements and Terminology . . . . . . . . . . . . . . . . . 3 2.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Load Sharing Strategy . . . . . . . . . . . . . . . . . . . . 3 4 PMN Handover Process . . . . . . . . . . . . . . . . . . . . . 5 5 Security Considerations . . . . . . . . . . . . . . . . . . . . 6 6 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6 7 References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7.1 Normative References . . . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 6 Haisheng Jiang Expires July 1, 2012 [Page 2] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 1. Introduction This specification describes the load sharing support for Mobile Access Gateways (MAG) in Proxy Mobile IPv6 (PMIPv6) [RFC5213] protocol. In PMIPv6, MAG performs the mobility-related signaling on behalf of the Mobile Nodes (MN) attached to the access links. A Local Mobility Domain (LMD) includes one Local Mobile Anchor (LMA) and multiple MAGs. With the number of MNs attaching to the specified MAG increasing, the overall traffic flow will surpass the processing capacity of the MAG. Thus MN will suffer from delay caused in the MAG, which will lower the transmission performance. So supplying the load sharing mechanism among MAGs can improve the data transmission capability for the PMIPv6 network. 2. Requirements and Terminology 2.1 Requirements 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]. 2.2 Terminology In addition to the terminology defined in [RFC5213], the following terminology is also used: Picked Mobile Node (PMN) - the MN selected by the scheme to migrate from the past MAG to the new MAG. The picking criterion is based on the traffic load stemming from the MN with some traffic parameters such as arrived rate of the traffic or the traffic pattern. 3. Load Sharing Strategy In PMIPv6 network, the MN migration from the overload MAG to some MAGs with low load can realize the load sharing among MAGs. In the initial stage, MAG measures the arrival rate of packets V1 from the MN. In general the access router is used as the MAG, so the packet process capacity V2 can be used to compare with V1. With the condition and weighted basis, the overload MAG initiates to perform the load sharing. The detailed comparative method can be discussed outside of this specification. The LMA located in a LMD will setup the bi-tunnel with each MAG. Load State Message (LSM) is used to periodically send the load information to LMA. The detailed message format is shown in Figure 1. A new flag (N) is included in the LSM message to reflect the MN attachment state of the MAG. The LSM is designated as MH type 10 in the Mobility Haisheng Jiang Expires July 1, 2012 [Page 3] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 Header as defined in Mobile IPv6 [RFC 6275]. In order to respond to the LSM from MAG, Load Sate Acknowledgement Message (LSAM) is utilized to send optional MAGs message to MAG for migrating the new arrival MN. The message format is presented in Figure 2. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence # | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |N| Reserved | Lifetime | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Mobility Options | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: LSM 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence # | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Reserved | Lifetime | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Mobility Options | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: LSAM According to the received load statement of those connected MAGs, LMA constructs an optional MN allocation set for the load sharing among MAGs. Based on MN attachment statement of the MN allocation set, LMA sends the LSAM to the MAG with the heaviest load. For the new arrival MNs, MAG compares the V1 with V2 and chooses the requirements of the MN with higher transmission rate as PMN. With this condition, the criterion generally depends on the service type of the MN. MN operating traditional Internet application such as text and web service with low delay requirements and packet loss can be selected as PMN. Haisheng Jiang Expires July 1, 2012 [Page 4] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 4 PMN Handover Process When the overloaded MAG initializes the load sharing process, the sequence of events illustrating the handover for PMN is shown in Figure 3. +---+ +-------+ +-------+ +-------+ +-------+ |PMN| | O-MAG | |MAG Set|->| A-MAG | | LMA | +---+ +-------+ +-------+ +-------+ +-------+ | access | | | | |----------->| | | | | | LSM | | |------------------------------>| | | | | | | | LSAM | | |<------------------------------| | | Request | | | | |-------->| | | | |feedback | | | | |<--------| | | | | select A-MAG | | | |------------------->| | |notification| | | | |<-----------| | | | | Router Solicitation | | |-------------------------------->| | | | | | PBU | | | | |--------->| | | | | PBA | | | | |<---------| | Router Advertisement | | |<--------------------------------| | | | | | | Figure 3: PMN Handover Process (a)According to the accessing message and the service type, the MN is picked as PMN. The overloaded MAG actives the load sharing process and sends LSM to LMA. (b)LMA gives a feedback with the load information of a MAG set with MAGs in the same LMD with the overload MAG and no overload. (c)The overload MAG sends handover request to one step MAGs. (d)Those MAGs give feedback with load information. (e)According to the comparing, the overload MAG selects the alternate MAG to migrate the PMN and sends information of PMN to the alternate Haisheng Jiang Expires July 1, 2012 [Page 5] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 MAG. (f)The overload MAG sends the message with the alternate MAG information to PMN to activate the migration. (g)PMN sends the Router Solicitation to the alternate MAG. (h)After the access authentication, the alternate MAG sends the PBU message to LMA. (i)LMA gives a PBA message to respond MAG. (j)The MAG sends a Router Advertisement with home network prefix to PMN. Through the bi-tunnel between PMN and alternate MAG, the new data transmission can be setup. 5 Security Considerations This document raises no new security issues for PMIPv6 network. 6 IANA Considerations None 7 References 7.1 Normative References [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC5213, August 2008. [RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support in IPv6", RFC6275, July 2011. Authors' Addresses Haisheng Jiang Huawei Building, No.156 Beiqing Rd. Z-park ,Shi-Chuang-Ke-Ji-Shi-Fan-Yuan,Hai-Dian District, Beijing 100095 P.R. China EMail: haisheng.jiang@huawei.com Haisheng Jiang Expires July 1, 2012 [Page 6] INTERNET DRAFT Load sharing for PMIPv6 December 29, 2011 Haisheng Jiang Expires July 1, 2012 [Page 7]