DemoIPv6Nemo

NEMO BS

Context

The IPv6 mobility is mainly managed by two protocols defined at IETF : Mobile IPv6 and NEMO BS (NEtwork MObility Basic Support). Mobile IPv6 enables single host mobility across different IPv6 networks whereas NEMO BS manages the mobility of an entire IPv6 network (known as mobile network). In NEMO BS, the mobility management is handled by a network entity called the mobile router. By this means, every movement (when the mobile network roams from one access network to another) is completely hidden to the nodes located in the mobile network. As a result, a legacy IPv6 node (when connected to a mobile network) can benefit from pervasive IPv6 connectivity without the needs of additional software or great configuration skills. Coupled with specific extensions, NEMO BS can also take benefit from multi-interfaced devices to enable multihoming support in the mobile network.

Through various ANR projects (e.g. REMORA) and research contracts, the "Networking & Protocols" research team works on several enhancements of this protocol:

• Bootstrapping autoconfiguration
  • Mobile routers autoconfiguration at start-up
  • Service discovery over the mobile network
• Multihoming
  • Load sharing and balancing
  • Fault tolerance
  • Auto-adaptive user softwares
  • Multiple mobile routers management

Showcase

Principle

To illustrate the mechanisms introduced by NEMO BS, we have set up a testbed which refers to a mobility provider scenario. When the mobile network roams between various access networks, the NEMO BS protocol maintains the continuity of user sessions and flows. Thanks to the NEMO BS mechanisms, such movement remains imperceptible for users.

Platform

The showcase platform introduces several entities:

• The mobility service
  • The home agent
  • The mobile router
• The IPv6 media servers
  • Video streaming (VLC)
  • Radio streaming (Icecast)
  • Voice over IP (AsteriskIPv6)
• The users of the mobile IPv6 network
  • IPv6 compliant operating system (Mac OS X, Windows Vista, GNU/Linux)
  • IPv6 compliant softwares (SIP-Communicator, VLC)
  • Laptop or tablet PC equipped with a wireless network interface (Wi-Fi)

Scenario

After the boot sequence, the mobile router is self-configured in order to provide a connectivity to the associated users. These users can auto-discover the IPv6 services provided by the operator. Finally, the moving router changes its access network and maintains the connexions in a invisible way for the users.

Service discovery

• At the operator level, the mobile router is self-configuring with the right parameters (prefix of the mobile network, address of the home agent, etc.).
• In the mobile network, the associated clients are IPv6 auto-configured and can discover the available services (VoD, VoIP).

Fig.1 Service discovery in a mobile network

Multihoming

Each stream is distributed over the available interfaces by order of preferences and in accordance to the protocol and the port used. Figure 2 illustrates a mobile router with 3 network connexions activated (2 Wi-Fi and 1 satellite). The VoIP stream is assigned to the satellite interface when available.

Fig.2 Multi interfaces

Mobility management

The mobile router is always reachable through is main address, as well as the clients associated to the mobile network. The stream persistence is maintained by the home agent, which takes care of the stream redirection when the mobile router change its access network (Figure 3 and 4).

Fig.3 Mobility, access network A

Fig.4 Mobility, moving toward the access network B