DMM Working Group Kyoungjae Sun Internet Draft Younghan Kim Intended status: Informational Soongsil University Expires: Janurary 2017 July 6, 2016 Multicast Anchoring in DMM draft-kjsun-dmm-multicast-anchoring-03.txt 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 Janurary 5, 2017. Copyright Notice Copyright (c) 2015 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. Sun, et al. Expires January 5, 2017 [Page 1] Internet-Draft Multicast Anchoring in DMM July 2016 Abstract In this draft, we define multicast support functions in a Distributed Mobility Management (DMM) environment. Based on the decomposed mobility management functions in [RFC7429], each defined multicast support function can be located and operated with DMM functions. Table of Contents 1. Introduction ................................................ 2 2. Conventions and Terminology ................................. 3 3. Multicast Support Functions in DMM .......................... 3 3.1. Multicast Anchoring Function (Multicast AF) ............ 3 3.2. Multicast Group Management Function (Multicast GM) ..... 4 3.3. Multicast Forwarding Management Function (Multicast FM). 5 4. Deploying Multicast Functions into Current Approaches ....... 5 4.1. Distributed AM, LM, and FM : All-in-One ................ 6 4.2. Distributed AF-DP, LM and FM with centralized AF-CP .... 6 4.3. Distributed AF-DP and FM-DP with centralized AF-CP, LM, and FM-CP .......................... 6 5. Security Considerations ..................................... 6 6. IANA Considerations ......................................... 6 7. References .................................................. 7 7.1. Normative References ................................... 7 7.2. Informative References ................................. 8 8. Acknowledgments ............................................. 8 1. Introduction Based on [RFC7333], a multicast solution in Distributed Mobility Management (DMM) should be considered early in the process of designing protocol and deployment models. Multicast support in DMM should avoid inefficient methods, such as non-optimal forwarding or tunnel convergence. To support IP multicasting, we need several functions: a multicast routing protocol, membership management, etc. When we consider multicast support in DMM, we should determine how efficiently these functions can be operated with the mobility management functions in DMM. Possible use cases are already described in [Use Case for Multicast DMM]. However, since current DMM research considers control/data separation and functional decomposition, we need to define multicast support functions following decomposed DMM anchor functions and operate with them. Sun, et al. Expires January 5, 2017 [Page 2] Internet-Draft Multicast Anchoring in DMM July 2016 In this draft, we define multicast mobility management functions that enable us to deploy the DMM functions defined in [RFC7429]. We define multicast mobility management functions in a similar way because it is easier to deploy multicast mobility management functions with DMM functions. 2. Conventions and 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 RFC-2119 [RFC2119]. This document uses the terminology defined in [RFC5213], [RFC3810], and [RFC4601]. New entities are defined by relying on the DMM functions specified in [RFC7429]: 1. Anchoring Function (AF) is an allocation to a mobile node of an IP address (e.g. Home Address (HoA))) or prefix (e.g. Home Network Prefix (HNP)), topologically anchored by the advertising node. 2. Internetwork Location Management (LM) function manages and keeps track of the internetwork location of an Mobile Node (MN). The location information may be a binding of the advertised IP address/prefix (e.g. HoA or HNP) to the MN's IP routing address, or it may be a binding of a node that can forward packets destined for the MN. 3. Forwarding Management (FM) function intercepts and forwards a packet to/from the IP address/prefix assigned to the MN based on the internetwork location information, either to the destination or to some other network element that knows how to forward the packets to their destinations. 3. Multicast Support Functions in DMM In this chapter, we define functions to support multicasting in DMM environment. The multicast support of previous mobility management schemes (e.g., MIP and PMIP) deployed multicast router or MLD proxy functions into their mobility entities (e.g., HA, LMA, and MAG). According to the decomposition of previous mobility management functions and considering the separation of the control and data planes, a multicast support function also could be decompose into several functions. 3.1. Multicast Anchoring Function (Multicast AF) The multicast AF is defined as the anchoring point for multicast subscribers in DMM domain. It means that all multicast traffic from/to the DMM domain should be forwarded through the multicast AF. Sun, et al. Expires January 5, 2017 [Page 3] Internet-Draft Multicast Anchoring in DMM July 2016 Even if the multicast AF is anchor point for multicast traffic, it does not mean that it is anchor point for unicast traffic. In other words, this function could be deployed separately with the DMM AF (e.g. MTMA solution in [RFC7028]), or combined with the DMM AF (e.g. LMA in [RFC6224]). The multicast AF function provides connectivity to the multicast infrastructure out of the DMM domain. With the multicast AF, the network entity may be part of multicast tree. That is, multicast AFs have a Tree Information Base (TIB). It could be act role of MLD proxy function which generate MLD membership report or user-defined subset in the its upstream interface. In addition, the multicast AF acts as MLD Querier of other MLD proxy instances located in DMM. To support multicast listeners, the multicast AF collects MLD report messages from mobile nodes or other entities (e.g. MLD proxy defined in [RFC4605]). To provide an appropriate multicast subscription, the multicast AF should join/prune multicast channels based on MLD reports from the mobile nodes. To support the multicast sender, this function forwards the source information of the sender to the Rendezvous Point (RP) in multicast infrastructure. The multicast AF could be separated into control-plane function and data-plane function. In that case, the multicast AF Control Plane (multicast AF-CP) is responsible of managing multicast tree information and sharing source information through multicast infrastructure. In other words, the multicast AF-CP acts as MLD Querier for the DMM domain and MLD proxy for the multicast infrastructure. For that, the multicast AF-CP maintains multicast forwarding states at its corresponding downstream interface and aggregated multicast membership states at its upstream interface. The multicast Data Plane (multicast AF-DP) is responsible of anchoring multicast data packets destined to the appropriate subscribers in the DMM domain. It should forward multicast traffic according to the multicast forwarding rules configured by the multicast AF-CP. 3.2. Multicast Group Management Function (Multicast GM) The multicast GM function is partially acts as MLD proxy which manages multicast subscriber information. According to [RFC4605], the MDL proxy devices maintain the membership database, which considers merging all subscriptions on the downstream interface. The membership database is presented a set of membership records, multicast addresses, filter modes and source lists. The multicast GM can maintain this database to support maintaining multicast subscribers and multicast sources. For that, the multicast AF function should create/delete/update membership database in the multicast GM when the mobile node join or leave multicast channel. Sun, et al. Expires January 5, 2017 [Page 4] Internet-Draft Multicast Anchoring in DMM July 2016 Especially the multicast GM support mobility management easily by requesting/updating subscriber information to this function. To track location of mobile node, the multicast GM can deployed with the location management function for DMM or can be extended flow entry table in that. Using this function, all multicast subscribers using the same multicast channel can be managed logically into the same records wherever they attach to so that it can avoid tunnel convergence problem. For example, even though two different nodes subscribing same multicast channel from different access router are moving to the same access node, the multicast GM can support to use only one upstream interface to the same multicast source address by updating its database and signaling with access node. Additionally the multicast GM function can support optimal multicast routing which sender and receiver are connected in the DMM domain. According group database in the multicast GM and location information of mobile nodes, in case that both sender and subscriber are located in DMM domain, the multicast AF can forward multicast packets directly to the access node where receiver is located in. 3.3. Multicast Forwarding Management Function (Multicast FM) The multicast FM function manages forwarding states that is used to forward packets from a source to a multicast group. Forwarding states could be managed together or separately with unicast forwarding states handled by the DMM FM function. In the former case, the multicast FM function should be located at the same entity where the DMM FM function is deployed (e.g. MAG function in [RFC7028] and [RFC6224]). Basically the multicast FM function maintains forwarding rules for routing from/to multicast infrastructure and multicast subscribers, and additionally it can be used specific forwarding mechanism such as PMIP or GRE tunneling between multicast FM entities to support mobility. The multicast FM function can be split into the control and data plane. The multicast FM control plane (FM-CP) performs multicast routing mechanism, makes forwarding rules for multicast traffic and commands to the multicast Fm data plane (FM-DP). For communication between control and data plane, [dmm-fpc-cpdp] can be a method for configuring forwarding policies. Rule of forwarding multicast traffic can be considered in various way; a set of forwarding rules of multicast subscribers or a single rule for each multicast channel. 4. Considering multicast functions into current approaches In this section, we consider how multicast functions can be merged with DMM functional deployment model. In this section, based on DMM functional deployment model in [sijeon-dmm-deployment-models], we make use cases which combine or separate multicast functions as we defined in previous section. Sun, et al. Expires January 5, 2017 [Page 5] Internet-Draft Multicast Anchoring in DMM July 2016 4.1. Distributed AM, LM, and FM : All-in-One In this model, all of DMM anchor functions (AF, FM, LM) are combined into one physical entity and such physical entities are distributed at the edge of network. This model is presented in [seite-dmm-dma] and [bernardos-dmm-pmip] To support multicast, the multicast anchor functions may be deployed together in mobility router. Optionally, in case of central LM usage, the multicast GM entity also may be centralized. On the other hand, one or more multicast entity also may be deployed independently. For example, in case of deploying the multicast AF functions separately, Signaling messages for supporting mobility are required between All-in-One DMM entity and the multicast AF. In this example, DMM entity which includes the multicast FM function can perform as multicast proxy. 4.2. Distributed AF-DP, LM and FM with centralized AF-CP This model separates AF function into control and data plane. AF-DP is distributed with LM and FM while AF-CP is centralized in a single entity. In this model, centralized AF-CP can determine AF-DP based on policy or network condition. As presented in [RFC7389], specific routing protocol, such as GTP or GRE, can be used to forward MN's traffic between AF-DPs. To support multicast in this model, the multicast AF-CP may be co- located where DMM AF-CP is placed. The multicast AF-DP may deploy together with DMM AF-DP or separately. In the latter case, like as Multimedia Broadcast Multicast Service (MBMS) gateway in [3GPP TS 36.440], specific AF-DP gateway can be used. Centralized AF-CP which includes multicast AF-CP can determine the multicast AF-DP for forwarding multicast traffic of MN. 4.3. Distributed AF-DP and FM-DP with centralized AF-CP, LM, and FM-CP This model considers separation of FM-CP and FM-DP with separation of AF-CP and AF-DP. In this model, forwarding path between AF-DP can be provided more flexible. [matsushima-stateless-uplane-vepc] is one example of this model. To support multicast in this model, multicast FM-CP, AF-CP and GM may be implemented in centralized control plane of DMM. In this case, signaling messages between control and data plane can be used by extending messages which could be used in normal DMM. For example, [dmm-fpc-cpdp] can be extended to make rule for multicast traffic by defining group forwarding rules. 5. Security Considerations TBD 6. IANA Considerations TBD Sun, et al. Expires January 5, 2017 [Page 6] Internet-Draft Multicast Anchoring in DMM July 2016 7. References 7.1. Normative References [RFC2119] S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 7.2. Informative References [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., Patil, B., "Proxy Mobile IPv6", RFC 5213, August 2008. [RFC3810] Vida, R., Costa, L., "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004. [RFC4601] Fenner, B., Handley, M., Holbrook, H., Kouvelas, I., "Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)", RFC 4601, August 2006. [RFC7429] Liu, D., Zuniga, JC., Seite, P., Chan, H., Bernardos, CJ., "Distributed Mobility Management: Current Practices and Gap Analysis", RFC 7429, January 2015. [RFC7333] Chan, H., Liu, D., Seite, P., Yokota, H., Korhonen, J., "Requirements for Distributed Mobility Management", RFC 7333, August 2014. [Use Case for Multicast DMM] Figueiredo, S., Jeon, S., Aguiar, R., L., "IP Multicast Use Cases and Analysis over Distributed Mobility Management", draft-sfigueiredo-multimob-use-case- dmm-03, October 2012 (Expired). [RFC4605] Fenner, B., He, H., Haberman, B., Sandick, H., "Internet Group Management Protocol (IGMP) / Multicast Listener Discovery (MLD)-Based Multicast Forwarding ("IGMP/MLD Proxying")", RFC 4605, August 2006. [RFC6224] Schmidt, T., Waehlisch, M., Krishnan, S., "Base Deployment for Multicast Listener Support in Proxy Mobile IPv6 (PMIPv6) Domains", RFC 6224, April 2011. [dmm-fpc-cpdp] Liebsch, M., Matsushima, S., Gundavelli, S., Moses, D., Bertz, L., "Protocol for Forwarding Policy Configuration (FPC) in DMM", draft-ietf-dmm-fpc-cpdp-03 (work in progress), March 2016. [sijeon-dmm-deployment-models] Jeon, S., Kim, Y., "Deployment Models for Distributed Mobility Management", draft-sijeon-dmm- deployment-models-02 (work in progress), March 2016. Sun, et al. Expires January 5, 2017 [Page 7] Internet-Draft Multicast Anchoring in DMM July 2016 [seite-dmm-dma] Seite, P., Bertin, P., and J. Lee, "Distributed Mobility Anchoring" (Expired), draft-seite-dmm-dma-07, February 2014. [bernardos-dmm-pmip] Bernardos, C., Oliva, A., and F. Giust, "A PMIPv6-based solution for Distributed Mobility Management", draft-bernardos-dmm-pmip-06 (work in progress), March 2016. [RFC7389] Wakikawa, R., Pazhyannur, R., Gundavelli, S., and C. Perkins, "Separation of Control and User Plane for Proxy Mobile IPv6", RFC 7389, October 2014. [3GPP TS 36.440] ETSI TS 36.440 v12.0.0, "LTE; Evolved Universal Terrestrial Radio Access Network (E-UTRAN); General aspects and principles for interfaces supporting Multimedia Broadcast Multicast Service (MBMS) within E-UTRAN (3GPP TS 36.440 version 12.0.0 Release 12)", September 2014. [matsushima-stateless-uplane-vepc] Matsushima, S. and R. Wakikawa, "Stateless user-plane architecture for virtualized EPC (vEPC)", draft-matsushima-stateless-uplane-vepc-06 (work in progress), March 2016. 8. Acknowledgments Sun, et al. Expires January 5, 2017 [Page 8] Internet-Draft Multicast Anchoring in DMM July 2016 Authors' Addresses Kyoungjae Sun Soongsil University 369, SSnagdo-ro, Dongjak-gu Seoul, Korea Email: gomjae@dcn.ssu.ac.kr Younghan Kim Soongsil University 369, SSnagdo-ro, Dongjak-gu Seoul, Korea Email: younghak@ssu.ac.kr Sun, et al. Expires January 5, 2017 [Page 9]