Proxy Mobile IPv6 (or PMIPv6, or PMIP) is a network-based mobility management protocol standardized by IETF and is specified in RFC 5213. It is a protocol for building a common and access technology independent of mobile core networks, accommodating various access technologies such as WiMAX, 3GPP, 3GPP2 and WLAN based access architectures. Proxy Mobile IPv6 is the only network-based mobility management protocol standardized by IETF.
Network-based mobility management enables the same functionality as Mobile IP, without any modifications to the host's TCP/IP Protocol stack. With PMIP the host can change its point-of-attachment to the Internet without changing its IP address. Contrary to Mobile IP approach, this functionality is implemented by the network, which is responsible for tracking the movements of the host and initiating the required mobility signalling on its behalf. However, in case the mobility involves different network interfaces, the host needs modifications similar to Mobile IP in order to maintain the same IP address across different interfaces.
The "SaMOG" (S2a Mobility based on GTP) study item in 3GPP defines the interworking between mobile packet core and a trusted WLAN access network (3GPP TR 23.852). The interface that SaMOG defines for this interworking is the 3GPP S2a GTP interface.
+--------+ _----_ | +--------+ _----_ | | _( )_ | | | _( )_ | |----( Internet ) | | |----( Internet ) | (LMA) | (_ _) | | (LMA) | (_ _) | | '----' | | | '----' +--------+ | +--------+ | | | -- -- --- -- -- | _----_ -- -- | _( )_ -- -- | ( internet ) -- IP Network -- | (_ _) -- -- | '----' -- -- | | -- -- --- -- -- | +-----------+ / | | MAG |---- +-------------+ +-------------+ | +-----------+ |--- (Session Chaining) | | | | | | LMA |---- | MAG | | MAG | | +-----------+ | | | | | | +-------------+ +-------------+ | _----_ | | | | | _( )_ +-----+ +-----+ +-----+ +-----+ | --(IP Network )-- | AP | | AP | | AP | | AP | | | (_ _) | | (L2)| | (L2)| | (L2)| | (L2)| | | '----' | +-----+ +-----+ +-----+ +-----+ | +-----+ +-----+ . . . . | | MAG | | MAG | / / / / | +-----+ +-----+ MN | / | MN | Proxy Mobile IPv6: Flat Domain Model | Proxy Mobile IPv6: Domain Chaining |
Based on Open Internet StandardsNo client software requirementIP Address ContinuitySession Continuity when roaming within a single access technology domainThe mobile node can be an IPv4-client, IPv6 client or a dual stack clientThe transport network between LMA (Local Mobility Anchor) and MAG (Mobile Access Gateway) can be IPv4 or IPv6The tunnel between the LMA and MAG is a shared tunnelThe tunnel between LMA and MAG can be based on GRE or IP-in-IPNo packet fragmentation, as PMIP advertises adjusted MTU values on the access sideExtremely Light Weight Protocol, MAG function can be implemented on a low-cost access pointMinimal Handover LatencySignaling semantics are based on IPv6, but can be enabled on an IPv4 networkPMIPv6 signaling can be protected using standard IPsec transport mode ESPNatural Support for Client Mobility. The LMA is a Mobile IPv6 Home AgentProtocol Interface supported in 3GPP LTE ArchitectureStandard Protocol Glue for linking access technology domainsIndustry Wide Participation in StandardizationAdopted in 3GPP, WiMAX and 3GPP2 ArchitecturesCentral traffic aggregation for charging, policy enforcement, LI and DPI EnforcementSupported in all 3GPP LTE Packet Data Gateways (LMA function in PDN Gateway)Future proofThe PMIPv6 architecture defines following functional entities:
Local Mobility Anchor (LMA)Mobile Access Gateway (MAG)Mobile Node (MN)Correspondent Node (CN)- A mobile host enters a PMIP domain
- A Mobile Access Gateway on that link checks host authorization
- A mobile host obtains an IP address
- A Mobile Access Gateway updates a Local Mobility Anchor about the current location of a host
- Both MAG and LMA create a bi-directional tunnel
- A Mobile Access Gateway sends a Router Advertise message to MN with Care-of-Address
Access authentication and mobile node's identityMobile node's policy profileMAG and Authenticator CollocationControl Plane SecurityData Plane SecurityIPv4 Address Assignment over DHCPv4Stateless Autoconf for IPv6Selective IP Traffic Offload Support with Proxy Mobile IPv6Network-based Mobility Management in a local domain (Single Access Technology Domain)Inter-technology handoffs across access technology domains (Ex: LTE to WLAN, eHRPD to LTE, WiMAX to LTE)Access Aggregation replacing L2TP, Static GRE, CAPWAP based architectures, for 3G/4G integration and mobilityMobile Operators today are facing two fundamental challenges:
There is availability of only finite amount of licensed spectrum, limiting the number of mobile nodes that can be active at a point of time in the macro network. This is proving to be a major issue in high-density areas, such as San Francisco city.The exponential growth in the mobile data traffic is creating significant capacity problems in the mobile packet coreTo address these scaling challenges, mobile operators are exploring new technology approaches for expanding their network coverage by integrating alternative access technologies into a common mobile core. Specifically, Wireless LAN networks based on IEEE 802.11 standards is showing lot of promise.
Secondly, for addressing the issue with the massive growth in mobile data traffic, mobile operators are exploring new ways to offload some of the IP traffic flows at the nearest WLAN access edge wherever there is an internet peering point, as opposed to carrying it all the way to the mobility anchor in the home network. Not all IP traffic needs to be routed back to the home network; some of the non-essential traffic which does not require IP mobility support can be offloaded at the access edge gateway. This approach provides greater leverage and efficient usage of the mobile packet core with increased overall network capacity and by lowering transport costs. Approaches such as, Selective IP Traffic Offload Option can be provide the basic offload semantics.
Cisco PMIPv6: Network-Based Mobility Deployment GuideNokia Siemens NetworksStarent (now part of Cisco)Number of other LTE PGW vendorsOpenAirInterface Proxy Mobile IPv6 (OAI PMIPv6)OPMIP - an open-source implementation of the Proxy MIPv6 mobility management protocolUMIP - Mobile IPv6 and NEMO for LinuxInternet Standards (IETF)
S. Gundavelli, K. Leung, V. Devarapalli, K. Chowdhury, and B. Patil "Proxy Mobile IPv6", RFC 5213, August 2008R. Wakikawa and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", RFC 5844, May 2010A. Muhanna, M. Khalil, S. Gundavelli and K. Leung, "Generic Routing Encapsulation (GRE) Key Option for Proxy Mobile IPv6", RFC 5845, June 2010A. Muhanna, M. Khalil, S. Gundavelli, and K. Leung, "Binding Revocation for IPv6 Mobility", RFC 5846, June 2010V. Devarapalli, R. Koodli, H. Lim, N. Kant, S. Krishnan & J. Laganier, "Heartbeat Mechanism for Proxy Mobile IPv6", RFC 5847, June 2010S. Gundavelli, M. Townsley, O. Troan and W. Dec, "Address Mapping of IPv6 Multicast Packets on Ethernet", RFC 6085, January 2011T. Schmidt, M. Waehlisch, S. Krishna, "Base Deployment for Multicast Listener Support in Proxy Mobile IPv6", RFC 6224, April 2011J. Korhonen & V. Devarapalli, "Local Mobility Anchor (LMA) Discovery for Proxy Mobile IPv6", RFC 6097, February 2011J. Korhonen, J. Bournelle, K. Chowdhury, A. Muhanna, U. Meyer, "MAG & LMA Interactions with Diameter Server", RFC 5779, February 2011V. Devarapalli, A. Patel & K. Leung, "Mobile IPv6 Vendor Specific Option", RFC 5094, December 2007J. Korhonen, S. Gundavelli, H. Yokota, and X. Cui, "Dynamic LMA Assignment Support in Proxy Mobile IPv6", RFC 6463, December 2011F. Abinader, S. Gundavelli, K. Leung, S. Krishnan, and D. Premec, "Bulk Registration Support in Proxy Mobile IPv6", RFC 6602, April 2012F. Xia, B. Sarikaya, J. Korhonen, S. Gundavelli and D. Damic, "RADIUS Support for Proxy Mobile IPv6", RFC 6572, April 2012G. Keeni, K. Koide, S. Gundavelli, and R. Wakikawa, "Proxy Mobile IPv6 Management Information Base", RFC 6475, January 2012M. Liebsch, S. Jeong & Q. Wu, "Localized Routing Problem Statement", RFC 6275, June 2011S. Krishnan, R. Koodli, P. Loureiro, Q. Wu & A. Dutta, "Localized Routing for Proxy Mobile IPv6", RFC 6705, September 2012S. Gundavelli, X. Zhou, J. Korhonen, R. Koodli, G. Feige, "IPv4 Traffic Offload Option for Proxy Mobile IPv6 (SIPTO)" RFC 6909, April 2013S. Gundavelli, J. Korhonen, M. Grayson, K. Leung, & R. Pazhyannur, "Access Network Information Option for PMIPv6", RFC 6757, October 2012X. Zhou, J. Korhonen, C. Williams, and S. Gundavelli, "Prefix Delegation for PMIPv6", RFC 7148 February 2014S. Gundavelli, "Reserved IPv6 Interface Identifier for Proxy Mobile IPv6", RFC 6543 March, 2012M. Liebsch, P. Seite, H. Yokota, J. Korhonen & S. Gundavelli, "QoS Support for Proxy Mobile IPv6", RFC 7222 April 2014S. Krishnan, S. Gundavelli, M. Liebsch, H. Yokota & J. Korhonen, "Update Notifications for Proxy Mobile IPv6", RFC 7077, November 2013R. Wakikawa, R. Pazhyannur, S. Gundavelli & C. Perkins, "Separation of Control and User Plane for Proxy Mobile IPv6", RFC 7389, October 2014R. Pazhyannur, S. Speicher, S. Gundavelli, J. Korhonen & J. Kaippallimalil, "Extensions to the Proxy Mobile IPv6 (PMIPv6) ANI Option", RFC 7563, June 2015T. Melia & S. Gundavelli, "Logical Interface Support", http://datatracker.ietf.org/doc/draft-ietf-netext-logical-interface-support, September 2011CJ. Bernardos, "IP Flow Mobility Support for Proxy Mobile IPv6", http://datatracker.ietf.org/doc/draft-ietf-netext-pmipv6-flowmob, September 2011S. Gundavelli, "Applicability of Proxy Mobile IPv6 Protocol for WLAN Access Networks", http://tools.ietf.org/html/draft-gundavelli-netext-pmipv6-wlan-applicability, October 2011M. Liebsch & S. Gundavelli, "Proxy Mobile IPv6 inter-working with WiFi Access Authentication", http://tools.ietf.org/html/draft-liebsch-netext-pmip6-authiwk, February, 2011S. Gundavelli, M. Grayson, Y. Lee, H. Deng & H. Yokota, "Multiple APN Support for Trusted Wireless LAN Access", http://tools.ietf.org/html/draft-gundavelli-netext-multiple-apn-pmipv6, March 2012SDO Standards (3GPP, 3GPP2 & WiMAX)
3GPP SA2, "Architecture for Non-3GPP Access", 3GPP TS 23.402, http://www.3gpp.org/ftp/Specs/archive/23_series/23.402, October 20083GPP CT4, "Proxy Mobile IPv6 - Stage 3 Specification", 3GPP TS 29.275, http://www.3gpp.org/ftp/Specs/archive/29_series/29.275/29275-a20.zip, June 20113GPP2, "Network PMIP Support", X.S0061-0 v1.0, http://www.3gpp2.org/Public_html/specs/X.S0061-0_v1.0_081209.pdf, December 2008WIMAX, "NWG PMIPv6 Stage-3 Specification", http://members.wimaxforum.org/apps/org/workgroup/nwg/download.php/38973/01085_r000_NWG_R1.5_PMIPv6_Stage3_Specification_D1.zip, October 2008