Thierry Ernst - MOTOROLA Labs / INRIA

1
Mobile Networks Support in Mobile
IPv6draft-ernst-mobileip-v6-network-00.txt

• Thierry Ernst - MOTOROLA Labs / INRIA
• Ludovic Bellier - INRIA project PLANETE
• Claude Castelluccia - INRIA project PLANETE
• Hong-Yon Lach - MOTOROLA Labs
• http//www.inrialpes.fr/planete/pub/MobiNet/mobine
  t.html

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Mobile Networks

• Definition
• Mobile Network Mobile Router (MR) its
  attached Nodes and Routers.

• Aim of this work
• To provide continuous Internet connectivity to
  nodes located in the mobile network.
• To offer optimal routing between Correspondent
  Nodes (CNs) and nodes in the mobile network
  (MNNs).
• What does the Mobile IPv6 specification say
• Mobile IPv6 nodes may either be mobile hosts or
  mobile routers.
• But no explicit mention of mobile networks.

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Mobile Networks in Mobile IPv6Experimentation 1/2

• Francis Dupont INRIA IPv6 Implementation under
  FreeBSD 3.3
• MR has two interfaces
• BR home address of MR is next hop to the mobile
  network

lt home address 3ffe3061130100eui64

• Mobile Network attaches to foreign link
• MR obtains a care-of address on the foreign link
• MR registers care-of address with HA.
• HA performs proxy NDP on the home link for the
  MRs home address.

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Mobile Networks in Mobile IPv6Experimentation 2/2

• Packets sent from CN to MR
• HA intercepts packets addressed to MR
• HA tunnels packets to MRs care-of address
• gt No Problems works fine whether mobile is a
  HOST or a ROUTER

• Packets sent from CN to MNN
• BR has a route to the mobile network MR next
  hop towards MNN
• HA intercepts packets addressed to MR
• HA does not have an entry corresponding to the
  destination address of MNN
• Packet is sent by HA to the default route (i.e.
  BR)
• BR resends the packet which is intercepted by HA
  and so on
• gt Problems
• HA does not know how to route packets sent to
  MNN.
• How to perform route optimization between CN
  and MNN ?

5
Mobile IPv6 extensions Binding Updates with a
network scope

• All nodes in the mobile network have the same
  network prefix
• gt instruct HA and CNs to route all packets
  bearing a network prefix corresponding to the
  prefix of the the mobile network via the MRs
  care-of address
• Means
• A bit Prefix Scope Registration in the Binding
  Update option that tells BU contains a care-of
  address valid for a mobile network
• Mobile Network Prefix Sub-Option to carry prefix
  of the mobile network
• (i.e. the prefix of MRs interface in the
  mobile network , not MRs interface on the home
  link)

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 -----------
--------------------- Sub-O
ption Type Sub-Option Len Prefix Length
--------------------
------------

Mobile Network Prefix

3ffe3061130200/64
------------
--------------------
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Mobile IPv6 extensions Impact on the current
specification

• Reception at the HA / CN of a Mobile Network
  Prefix Sub-Option
• add an entry in the binding cache
• flag Prefix scope registration
• prefix length length of the mobile network
  prefix
• home address is filled with mobile network prefix
• care-of address as usual
• Sending Packets to MNN
• searching the binding cache for records where
  flag Prefix scope registrationis set, only the
  ltlengthgt initial bits are compared instead of the
  full 128-bits address
• packets are sent to the MNN via the care-of
  address of MR using a Routing Extension Header
• Security and authentication
• no additional problems
• BU are not sent on behalf of another node BUs
  are sent by the node that obtains the care-of
  address, i.e. the Mobile Router
• the sender of the BU is authenticated
• we assume that the Mobile Router is certified as
  an authorized router to send network scope BUs.

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Mobile Networks in Mobile IPv6 Summary

• Future needs require to consider (potentially
  large) mobile networks in IPv6.
• Problem
• Communication between CN and MNN is not possible.
• No optimal route between the CN and MNN
• This draft proposes minor Mobile IPv6 extensions
  to support mobile networks efficiently.
• we propose to send BUs with a network scope
• the care-of address carried in the BU is used
  for all destination address that share the same
  network prefix.
• means
• a new Sub-Option
• recording a prefix in the binding cache
• searching the binding cache for a prefix

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• For more information
• draft-ernst-mobileip-v6-network-00.txt
• http//www.inrialpes.fr/planete/pub/MobiNet/mobine
  t.html
• Thierry Ernst - MOTOROLA LABS / INRIA
• thierry.ernst_at_inrialpes.fr
• at INRIA Rhône-Alpes - project PLANETE
• http//www.inrialpes.fr/planete/people/ernst/Welco
  me.html