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/mobinet.html

Mobile Networks Support in Mobile IPv6

draft-ernst-mobileip-v6-network-00.txt

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

2Mobile 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.

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

3Mobile Networks in Mobile IPv6:Experimentation 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

• 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 MR’s home address.

< home address 3ffe:306:1130:100:eui64

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

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Packets sent from CN to MR:• HA intercepts packets addressed to MR

• HA tunnels packets to MR’s care-of address

=> 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 …

=> Problems:

• HA does not know how to route packets sent to MNN.

• How to perform “route optimization” between CN and MNN ?

Mobile Networks in Mobile IPv6:Experimentation 2/2

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

5Mobile IPv6 extensions: Binding Updates with a network scope

• All nodes in the mobile network have the same network prefix => instruct HA and CNs to route all packets bearing a network prefix corresponding

to the prefix of the the mobile network via the MR’s 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 MR’s interface in the mobile network , not MR’s 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-Option Type| Sub-Option Len| Prefix Length | |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| |+ Mobile Network Prefix +

| 3ffe:306:1130:200::/64 |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

6Mobile 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 registration”is

set, only the <length> 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.

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

7Mobile 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

48th IETF - draft-ernst-mobileip-v6-network-00.txt - July 2000

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For more information:draft-ernst-mobileip-v6-network-00.txt

http://www.inrialpes.fr/planete/pub/MobiNet/mobinet.html

Thierry Ernst - MOTOROLA LABS / INRIA

thierry.ernst@inrialpes.fr

at INRIA Rhône-Alpes - project PLANETE

http://www.inrialpes.fr/planete/people/ernst/Welcome.html