Proxy Mobile IPv6

Last updated

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.

Contents

Introduction

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.

Proxy Mobile IPv6 Deployment Models

               +--------+       _----_                 |                +--------+       _----_                |        |     _(      )_               |                |        |     _(      )_                |        |----( Internet )              |                |        |----( Internet )                              |  (LMA) |     (_      _)               |                |  (LMA) |     (_      _)                               |        |       '----'                 |                |        |       '----'                                 +--------+                              |                +--------+                                                   |                                  |                    |            /--------------------\                       |                  _----_          /                      \                      |                _(      )_         /                        \                     |               ( internet )        /       IP Network         \                    |                (_      _)        \                          /                    |                  '----'         \                        /                     |                     |           \----------------------/                      |               +-----------+            /                   \                       |               |    MAG    |----        +-------------+       +-------------+               |               +-----------+    |--- (Session Chaining)    |             |       |             |               |               |    LMA    |----     |     MAG     |       |     MAG     |               |               +-----------+    |             |       |             |               |                     |                  +-------------+       +-------------+               |                  _----_       |        |            |        |                 |                _(      )_        +-----+  +-----+      +-----+  +-----+              |            --(IP Network )--            |  AP |  |  AP |      |  AP |  |  AP |              |            |   (_      _)   |    | (L2)|  | (L2)|      | (L2)|  | (L2)|              |            |     '----'     |    +-----+  +-----+      +-----+  +-----+              |         +-----+           +-----+           abhishek thakur       .        .            .        .                 |         | MAG |           | MAG |         / \      / \          / \      / \                |         +-----+           +-----+                                    MN                                                  |            /\                                                        |            MN                                                                            |            Proxy Mobile IPv6: Flat Domain Model                  |    Proxy Mobile IPv6: Domain Chaining                                                        |

Key Properties of Proxy Mobile IPv6 Technology

Proxy Mobile IPv6: Technology Overview

Functional Entities

The PMIPv6 architecture defines following functional entities:

Messaging Call Flows

PMIPv6-IPv6-Signaling.jpg PMIPv6-CN6-to-MN6.jpg

Protocol Operation

  1. A mobile host enters a PMIP domain
  2. A Mobile Access Gateway on that link checks host authorization
  3. A mobile host obtains an IP address
  4. A Mobile Access Gateway updates a Local Mobility Anchor about the current location of a host
  5. Both MAG and LMA create a bi-directional tunnel
  6. A Mobile Access Gateway sends a Router Advertise message to MN with Care-of-Address

Access Authentication

Security Considerations

Address Assignment

Proxy Mobile IPv6: Technology Applications

Selective IP Traffic Offload (SIPTO) Support with Proxy Mobile IPv6

Mobile Operators today are facing two fundamental challenges:

To 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.

SIPTO.jpg

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.

How to Implement Proxy Mobile IPv6

Mobile Access Gateway

Functional BlockRequirementPlatform APIDescription
Trigger HandlerEvents: MN-ATTACHED, MN-DETACHED Parameters: Mac-Address, MN-Id (if present)Linux API - TBDThis functional block is required for detecting the triggers related to mobile node's attachment, detachment, address configuration and router discovery related events. The network triggers, ARP message for the default-router’s MAC address, Gratuitous ARP message, DHCP Request message, IPv6 ND messages are the potential triggers for the MAG to initiate PMIPv6 signaling. In some cases, trigger can also be based on detecting a new MAC address on the access link by other link-layer specific means. Refer to: RFC 5844, RFC 5213, RFC 4436, RFC 5227. The identity of the mobile node in these triggers is always the Mac address, except for DHCPv4, where the client-identifier option can potentially be the mobile node identifier (if set by the client or a transit node such as an access point, or a WLAN controller).
Identity ManagementGET-MN-Identity. Parameters: Mac Address, MN-IdTBDThe identity of the mobile node is tied to the access authentication. When the mobile node using 802.1x/EAP mechanisms complete the access authentication, its identity used for authentication and the corresponding Mac address of the MN is known. If access Authenticator function and the MAG are functionally collocated on the same node, it is internal to the implementation as how that mapping between the mobile node’s identity and its link-layer/Mac identifier is obtained. It is also possible these functions are hosted on different network nodes (Ex: Authenticator on the AP and the MAG on the Wireless-LAN-controller/first-hop-router), but with some protocol interface between the two nodes, that enables the MAG to obtain the mobile node's identity. Refer to Section 6.6, RFC 5213. When using Mac Address as the MN-Id, the security implications and the Mac address in the policy profile needs to be understood.
Policy ProfileGET-MN-Profile. Parameters: MN-IdTBDThe mobile's node policy profile identifies the service preferences for a given mobile node. Parameters such as PMIPV6 Domain, LMA IP Address, 3GPP APN ..etc., are present in the profile. Refer to Section 6.2, RFC 5213 This profile is typically on a central policy store such as AAA, or it can also be locally configured. Refer to PMIPv6 RADIUS draft, or PMIPv6 Diameter Interface (RFC 5779).
PMIPv6 SignalingPBU/PBA MessagesTBDThe options that are required in the PBU message are a.) Home Network Prefix option b.) IPv4 Home Address Request option c.) Access Technology Type option d.) Link-layer Identifier option e.) Handoff Indicator option. Other optional parameters such as Service Selection Option for carrying the 3GPP APN information, Access Network Information option, IPv4 Traffic Offload Option, and any Vendor Specific options. Refer to Section 8 (RFC 5213). Section 3 (RFC 5844), Section 3 (RFC 5094), Section 3 (RFC 5149). The PBU is just MIPv6 BU message. Any of the MIPv6 Open source implementations can be used as the messaging library after adding the new options.
DHCPv4 InteractionsGet-IP-Address-From-LMA, Assign-IP-Address-To-MN. Parameters: MN-Id, Mac Address, IPv4 home Address, Subnet Mask, Default-router AddressExampleThe mobile node obtains its IPv4 address using DHCPv4. RFC-5844 supports two modes of DHCP configurations, DHCP server collocated on the MAG and the DHCP Relay collocated on the MAG. Implementing DHCP server (minimalistic) collocation on the MAG is the simpler approach. The needed interactions are the ability to influence the DHCP server to assign an IPv4 address that the MAG obtained from LMA over PMIPv6 signaling plane. When there is DHCP Discover request from the mobile node, the DHCP server should trigger the MAG and the MAG should return the IP address after completing the PMIPv6 signaling with the mobile node's LMA. The DHCP server should assign the IP address that it obtains from the LMA. The MAG should also be able to respond to any ARP requests for the default-router address.
Tunnel ManagementCreate-Tunnel, Delete Tunnel. Parameters: Encap-Type, IP Source Address, IP Destination AddressExamplePMIPv6 specifications support GRE, IP-in-IP encapsulation modes. In other words, the tunnel encapsulations can be IPv4-GRE, IPv6-GRE, IPv4 and IPv6. The payload packet can be IPv4, or IPv6, carried with the negotiated tunnel encap. The linux open source package, IPRoute2, support both these encapsulation modes.
IP ForwardingAdd-IPv4-Tunnel-Route, Delete-IPv4-Tunnel-Route, Add-Reverse-Tunnel-Policy-Route, Delete-Reverse-Tunnel-Policy-Route. Parameters: IPv4 Address, IPv6-Prefix, Tunnel-Interface-Id, MN-MAG-Interface-Id.TBDThe MAG should ensure any IPv4 or IPv6 packets from the mobile node using the IP addresses assigned by the LMA, should be reverse tunneled over the PMIPv6 LMA tunnel. Typically, a PBR route tied to the MAC address, source IPv4 address, source IPv6 prefix in the packet headers can be used for selecting the packet for reverse tunneling. When local-routing is enabled, there are some optimizations needed.

Local Mobility Anchor

Functional BlockRequirementPlatform APIDescription
Proxy ModelTBDTBDExtend open source MIPv6 Home Agent to support PMIPv6
Addressing ModelTBDTBDTBD
Security ModelTBDTBDTBD
Data StructuresTBDTBDExtend the BCE table with new parameters, define new PMIPv6 mobility options

Proxy Mobile IPv6 Implementations

Proxy Mobile IPv6 Specifications

Internet Standards (IETF)

SDO Standards (3GPP, 3GPP2 & WiMAX)

See also

Related Research Articles

The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network using a client–server architecture.

An Internet Protocol address is a numerical label such as 192.0.2.1 that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface identification, and location addressing.

<span class="mw-page-title-main">IPv4</span> Fourth version of the Internet Protocol

Internet Protocol version 4 (IPv4) is the first version of the Internet Protocol (IP) as a standalone specification. It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version deployed for production on SATNET in 1982 and on the ARPANET in January 1983. It is still used to route most Internet traffic today, even with the ongoing deployment of Internet Protocol version 6 (IPv6), its successor.

<span class="mw-page-title-main">IPv6</span> Version 6 of the Internet Protocol

Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. IPv6 was developed by the Internet Engineering Task Force (IETF) to deal with the long-anticipated problem of IPv4 address exhaustion, and was intended to replace IPv4. In December 1998, IPv6 became a Draft Standard for the IETF, which subsequently ratified it as an Internet Standard on 14 July 2017.

In computing, Internet Protocol Security (IPsec) is a secure network protocol suite that authenticates and encrypts packets of data to provide secure encrypted communication between two computers over an Internet Protocol network. It is used in virtual private networks (VPNs).

<span class="mw-page-title-main">Subnet</span> Logical subdivision of an IP network

A subnetwork, or subnet, is a logical subdivision of an IP network. The practice of dividing a network into two or more networks is called subnetting.

SOCKS is an Internet protocol that exchanges network packets between a client and server through a proxy server. SOCKS5 optionally provides authentication so only authorized users may access a server. Practically, a SOCKS server proxies TCP connections to an arbitrary IP address, and provides a means for UDP packets to be forwarded. A SOCKS server accepts incoming client connection on TCP port 1080, as defined in RFC 1928.

In Internet networking, a private network is a computer network that uses a private address space of IP addresses. These addresses are commonly used for local area networks (LANs) in residential, office, and enterprise environments. Both the IPv4 and the IPv6 specifications define private IP address ranges.

Mobile IP is an Internet Engineering Task Force (IETF) standard communications protocol that is designed to allow mobile device users to move from one network to another while maintaining a permanent IP address. Mobile IP for IPv4 is described in IETF RFC 5944, and extensions are defined in IETF RFC 4721. Mobile IPv6, the IP mobility implementation for the next generation of the Internet Protocol, IPv6, is described in RFC 6275.

The IP Multimedia Subsystem or IP Multimedia Core Network Subsystem (IMS) is a standardised architectural framework for delivering IP multimedia services. Historically, mobile phones have provided voice call services over a circuit-switched-style network, rather than strictly over an IP packet-switched network. Various voice over IP technologies are available on smartphones; IMS provides a standard protocol across vendors.

The Host Identity Protocol (HIP) is a host identification technology for use on Internet Protocol (IP) networks, such as the Internet. The Internet has two main name spaces, IP addresses and the Domain Name System. HIP separates the end-point identifier and locator roles of IP addresses. It introduces a Host Identity (HI) name space, based on a public key security infrastructure.

The Neighbor Discovery Protocol (NDP), or simply Neighbor Discovery (ND), is a protocol of the Internet protocol suite used with Internet Protocol Version 6 (IPv6). It operates at the internet layer of the Internet model, and is responsible for gathering various information required for network communication, including the configuration of local connections and the domain name servers and gateways.

GPRS Tunnelling Protocol (GTP) is a group of IP-based communications protocols used to carry general packet radio service (GPRS) within GSM, UMTS, LTE and 5G NR radio networks. In 3GPP architectures, GTP and Proxy Mobile IPv6 based interfaces are specified on various interface points.

Anything In Anything (AYIYA) is a computer networking protocol for managing IP tunneling protocols in use between separated Internet Protocol networks. It is most often used to provide IPv6 transit over an IPv4 network link when network address translation masquerades a private network with a single IP address that may change frequently because of DHCP provisioning by Internet service providers.

In computer networking, a link-local address is a network address that is valid only for communications on a local link, i.e. within a subnetwork that a host is connected to. Link-local addresses are most often unicast network addresses assigned automatically through a process known as stateless address autoconfiguration (SLAAC) or link-local address autoconfiguration, also known as automatic private IP addressing (APIPA) or auto-IP. Link-local addresses are not all unicast; e.g. IPv6 addresses beginning with ff02:, and IPv4 addresses beginning with 224.0.0. are multicast addresses that are link-local.

System Architecture Evolution (SAE) is the core network architecture of mobile communications protocol group 3GPP's LTE wireless communication standard.

IP networks are divided logically into subnetworks. Computers in the same subnetwork have the same address prefix. For example, in a typical home network with legacy Internet Protocol version 4, the network prefix would be something like 192.168.1.0/24, as expressed in CIDR notation.

<span class="mw-page-title-main">Locator/Identifier Separation Protocol</span>

Locator/ID Separation Protocol (LISP) is a "map-and-encapsulate" protocol which is developed by the Internet Engineering Task Force LISP Working Group. The basic idea behind the separation is that the Internet architecture combines two functions, routing locators and identifiers in one number space: the IP address. LISP supports the separation of the IPv4 and IPv6 address space following a network-based map-and-encapsulate scheme. In LISP, both identifiers and locators can be IP addresses or arbitrary elements like a set of GPS coordinates or a MAC address.

NAT64 is an IPv6 transition mechanism that facilitates communication between IPv6 and IPv4 hosts by using a form of network address translation (NAT). The NAT64 gateway is a translator between IPv4 and IPv6 protocols, for which function it needs at least one IPv4 address and an IPv6 network segment comprising a 32-bit address space. The "well-known prefix" reserved for this service is 64:ff9b::/96.

<span class="mw-page-title-main">Multipath TCP</span> Transmission Control Protocol technology

Multipath TCP (MPTCP) is an ongoing effort of the Internet Engineering Task Force's (IETF) Multipath TCP working group, that aims at allowing a Transmission Control Protocol (TCP) connection to use multiple paths to maximize throughput and increase redundancy.

References

  1. "Proxy Mobile IPv6: Network-Based Mobility Deployment Guide - Proxy Mobile IPv6 Network-Based Mobility [Cisco IOS XE 3S]". Cisco.
  2. "OpenAirInterface Proxy Mobile IPv6 (OAI PMIPv6) | Open Air Interface". Archived from the original on 2013-01-14. Retrieved 2012-07-02.
  3. "OPMIP - ATNoG - Aveiro Telecommunications and Networking Group (TN-AV)". atnog.av.it.pt.
  4. "UMIP - Mobile IPv6 and NEMO Basic Support implementation for Linux". umip.org.