NEMO Working Group Eranga Perera
INTERNET DRAFT UNSW
29th July 2003 Robert Hsieh
UNSW
Aruna Seneviratne
UNSW
Extended Network Mobility Support
draft-perera-nemo-extended-00.txt
Status of This Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
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Abstract
This draft proposes a solution for extended network mobility support,
that is a mechanism to enable optimal routing between mobile network
nodes and its correspondent nodes. The proposed scheme not only
provides optimal routing for the mobility aware nodes but also
maintains the benefits of mobility transparency. Our solution
achieves route optimization by expecting the Mobile Router to take
the role of an Access Router thereby reducing the number of external
signaling messages a node behind the Mobile Router needs to perform.
In order to further reduce the number of signaling messages beyond
the scope of the mobile network we further propose the Mobile Router
to play the role of an Home Agent for NEMO-enabled nodes.
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Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1 Dual Roles of the Mobile Router. . . . . . . . . . . . . . 7
3.1.1 Mobile Router as an Access Router. . . . . . . . . . 7
3.1.2 Mobile Router as a Home Agent. . . . . . . . . . . . 8
3.2 Enabling Route Optimization for the Mobile Network Nodes . 9
3.2.1 Enabling Route Optimization for the Mobile Router. . 9
3.2.2 Enabling Route Optimization for Nodes behind the
Mobile Router. . . . . . . . . . . . . . . . . . . . 9
4. Mobile Router Operations . . . . . . . . . . . . . . . . . . . 10
4.1 Mobile Router Operations as an Access Router. . . . . . . . 10
4.2 Mobile Router operations as a Home Agent. . . . . . . . . . 11
4.2.1 Process of Discovering the Mobile Router . . . . . . 11
4.2.2 Establishment of a Bidirectional between the Mobile
Router and the NEMO-enabled nodes . . . . . . . . . 12
4.2.3 Establishment of a Bidirectional tunnel between the
Mobile Router and its Home Agent . . . . . . . . . . 12
5. Mobile Router's Home Agent Operations . . . . . . . . . . . . . 13
6. Mobile Network Nodes Route Optimization Operations . . . . . . 14
6.1 MIPv6-enabled Mobile Network Nodes Route Optimization
operations . . . . . . . . . . . . . . . . . . . . . . . . 14
6.2 NEMO-enabled Local Mobile Node and Local Fixed Node
Operations . . . . . . . . . . . . . . . . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
The basic NEMO protocol [1] provides session continuity to all the
nodes in the mobile network. This is achieved by creating a
bidirectional tunnel between the Mobile Router and its Home Agent.
Although this is achieved while providing complete mobility
transparency to the nodes within the network, the solution forces all
datagrams for a mobile node to be routed through the Home Agent. Our
solution proposes a mechanism in order to overcome this indirect
routing and provide route optimization for all MIPv6-enabled nodes of
a mobile network.
In MIPv6 [2] route optimization provide a means for mobile nodes to
send their current mobility bindings, in particular, the care-of
address to the correspondent nodes, enabling direct communication. It
is evident that in order for a mobile node to perform route
optimization, it should be aware of its current location.
If we were to provide network mobility transparency to all nodes
within the mobile network, as the mobile nodes within the mobile
network are unaware of their current location, would need to depend
on the Mobile Router to deal with all mobility management issues
including route optimization. We advocate on not adhering to the
design goal of network mobility transparency when providing extended
mobility support. We believe that allowing a mobile node to handle
sending Binding Updates to its correspondent nodes is a much secure
task than depending on another node to perform this task. Our scheme
preserves benefits of mobility transparency when providing optimal
routing for MIPv6-enabled nodes. This is achieved by extending the
Mobile Router's operations, in order to limit the signaling that a
mobile network node needs to perform beyond the scope of the mobile
network to a minimum.
Although our solution would only support MIPv6-enabled nodes in
optimal routing our solution does not inhibit in anyway the correct
operation of the NEMO basic protocol for mobility unaware nodes. Our
solution is backward compatible with MIPv6 and also compatible with
the solution for basic NEMO support.
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2. Terminology
This document uses the mobility related terminology defined in [2],
[3] and [4].
The following terms are used as defined in [2].
- Home Agent
- Home Address
- Care-of Address
- Binding Update
The following terms defined in [3] specific to network mobility are
used in this draft.
- Local Mobile Node
- Local Fixed Node
- Visiting Mobile Node
- Mobile Network Node
- Correspondent Nodes
- Home Subnet Prefix
- MIPv6-enabled (MIPv6-node)
- Node behind the Mobile Router
Except for the definitions of the terms 'Mobile Router' and
'NEMO-enabled' the rest of the above terms are used as per
definitions in [3]. Before presenting our extensions to the
definition of a Mobile Router we state the definitions of a Home
Agent [2] and Access Router [4], since our definition relies on these
two terms.
Access Router -
An Access Network Router residing on the edge of an Access Network
and connected to one or more Access Points. The Access Points
maybe of different technology. An Access Router offers IP
connectivity to Mobile Nodes, acting as a default router to the
Mobile Nodes it is currently serving. The Access Router may
include intelligence beyond a simple forwarding service offered
by ordinary IP routers.
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Home Agent -
A router on a mobile node's home link with which the mobile node
has registered its current care-of address. While the mobile
node is away from home, the Home Agent intercepts packets on the
home link destined to the mobile node's home address,
encapsulates them, and tunnels them to the mobile node's
registered care-of address.
Mobile Router -
A router capable of changing its point of attachment to the
network, moving from one link to another link. The Mobile Router
is capable of forwarding packets between two or more interfaces,
and possibly running a dynamic routing protocol modifying the
state by which to do packet forwarding.
The interface of a Mobile Router attached to a link inside the
mobile network is called the Ingress interface. The interface of a
Mobile Router attached to the home link if the Mobile Router is at
home, or attached to a foreign link if the Mobile Router is in a
foreign network is called the Egress interface.
A Mobile Router acting as a gateway between an entire mobile
network and the rest of the Internet has one or more Egress
interface(s) and one or more Ingress interface(s). Packets
forwarded upstream to the rest of the Internet are transmitted
through one of the Mobile Router's Egress interfaces; packets
forwarded downstream to the mobile network are transmitted through
one of the Mobile Router's Ingress interfaces.
Our extension to this definition -
A router capable of playing the role of a Home Agent for the
Local Mobile Nodes and Local Fixed Nodes belonging to its home
network link and playing the role of an Access Router for Local
Mobile Nodes, Local Fixed Nodes, Visiting Mobile Nodes.
NEMO-enabled -
A MIPv6-enabled Local Mobile Node or Local Fixed Node that is
capable of dynamically reconfiguring its Home Agent to be the
Mobile Router when the Mobile Network is attached to a foreign
link.
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [].
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3. Overview
This scheme provides a mechanism to enable route optimization for the
mobile network nodes that are MIPv6-enabled. One might question the
need for the Mobile Router's participation in the mobility management
of these nodes when they are MIPv6-enabled. The reason for relying on
the Mobile Router to perform certain tasks for the nodes behind it,
is to preserve the benefits of mobility transparency. Consider a
mobile network scenario of an aircraft with potentially many Visiting
Mobile Nodes (passengers with mobile devices), Local Fixed Nodes
(fixed terminals on every seat for Internet access) and Local Mobile
Nodes (mobile devices that belong to aircraft personnel). In such a
scenario, as the aircraft moves each of the above mentioned devices
would need to communicate with an external Access Router in order to
get the prefix of the new access network. These mobile devices would
need to be technologically sophisticated to communicate with external
Access Routers potentially via satellite links. These devices can
overcome such technical difficulties and minimize the number of
signaling messages beyond the scope of the mobile network by relying
on the Mobile Router to perform the tasks of an Access Router for the
nodes sitting behind it.
Consider in the above aircraft scenario the need for each Local
Mobile Node and Local Fixed Node having to send a separate Binding
Update to their respective Home Agents. We advocate on making these
nodes to be NEMO-enabled in order to avoid the need for individual
Binding Updates to be sent to their Home Agents. The Mobile Router
can send one Binding Update to a Home Agent on the Home network
representing itself and the NEMO-enabled nodes behind it. This
mechanism reduces the number of external signaling messages a
NEMO-enabled node needs to perform, reduces the overall usage of
bandwidth beyond the scope of the mobile network and also reduces the
burden on the Home Agent residing on the home network. By requiring
the Mobile Router to play the role of a Home Agent for NEMO-enabled
nodes, our scheme introduces a hierarchical Home Agent structure for
network mobility which is depicted in figure 1.
__|_
| |
| HA | <----- Mobile Router's Home Agent
|____|
______|__
_|__
| |
| MR | <----- NEMO-enabled node's Home Agent
|____|
|
_____|_____________________________
__|__ __|__ __|__
| | | | | |
| LFN | | LMN | | LFN | . . . . . . .
|_____| |_____| |_____|
Figure 1: Hierarchical Home Agent Structure
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3.1 Dual Roles of the Mobile Router
This section provides an overview of roles that the Mobile Router
performs in order to preserve the benefits of hiding mobility from
the nodes within the mobile network.
3.1.1 Mobile Router as an Access Router
The Mobile Router when attached to a foreign network will
obtain a prefix pertaining to the new network. Once this is
done the Mobile Router will act as an Access Router for the
nodes behind it and will send Router Advertisement messages
on its Ingress interface. Any MIPv6-enabled node sitting
behind the Mobile Router will be able to use the prefix
advertised by the Mobile Router and using stateless address
auto configuration [5] form a care-of address for itself.
Figure 2 depicts an instance of the Mobile Router playing the
role of an Access Router to MIPv6-enabled Local Mobile Nodes,
Local Fixed Nodes and Visiting Mobile Nodes.
____ ____
| | | |
| CN | | CN |
|____| |____|
___|_______________|____
| |
| |
| Internet |
| |
|________________________|
__|_ __|_
| | Access | |
| AR | Router | AR |
|____| |____|
______|__ Foreign
_|__ Link
| |
| MR |
|____|
|<------- Access Router Mode
_____|______________________
__|__ __|__ __|__
| | | | | |
| VMN | | LMN | | LFN |
|_____| |_____| |_____|
Figure 2: Instance of a Mobile Router playing the role of
an Access Router
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3.1.2 Mobile Router as a Home Agent
NEMO-enabled nodes sitting behind the Mobile Router can
further reduce the number of external signaling messages by
relying on the Mobile Router to perform the role of a Home
Agent for them. Since a Home Agent is a router that resides in
a mobile nodes home network we can take the Mobile Router to
be a Home Agent for the Local Fixed Nodes and the Local Mobile
Nodes because with respect to the Mobile Router's topology
these nodes are at home. These nodes would obtain a prefix
from the Access Router that is the Mobile Router and auto
configure a care-of address. These operations will not differ
from a standard MIPv6 mobile node operations. The NEMO-enabled
nodes will register its current care-of address with the
Mobile Router by dynamically configuring the Mobile Router to
be their Home Agent if they belong to the Mobile Router's home
network. Mobile Router would send an aggregated Binding Update
to the Home Agent residing in the home network to which this
mobile network belongs, reducing the usage of bandwidth. The
Mobile Router on receiving any packets for the registered
nodes will tunnel these packets to the registered care-of
addresses of the NEMO-enabled nodes. Figure 3 depicts an
instance of a Mobile Router playing the role of a Home Agent
for NEMO-enabled nodes.
____ ____
| | | |
| CN | | CN |
|____| |____|
___|_______________|____
| |
| |
| Internet |
| |
|________________________|
__|_
| | Access
| AR | Router
|____|
______|__ Foreign
_|__ Link
| |
| MR |
|____|
|<------- Home Agent Mode
_____|______________________
__|__ __|__
| | | |
| LMN | | LFN |
|_____| |_____|
Figure 3: Mobile Router playing the role of a Home Agent
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3.2 Enabling Route Optimization for the Mobile Network Nodes
This section provides an overview of the route optimization procedure
for MIPv6-enabled mobile network nodes.
3.2.1 Enabling Route Optimization for the Mobile Router
The Mobile Router acting as a Mobile Node can register its
care-of address with a Home Agent as well as its Correspondent
Nodes. This enables direct communication between the Mobile
Router and the MIPv6-enabled Correspondent Nodes. This operation
does not differ from standard MIPv6 route optimization procedure
for a Mobile node. If the Mobile Router is operating as a Home
Agent then the Mobile Router would send a Binding Update to its
Home Agent representing the nodes registered with it according
to the NEMO basic protocol.
3.2.2 Enabling Route Optimization for MIPv6-enabled nodes sitting
behind the Mobile Router
These nodes can obtain prefix information pertaining to the
current position of the Mobile Network from the Mobile Router,
now acting as an Access Router. This process will be described in
detail in Section 4. Once the prefix is obtained these nodes can
auto configure a care-of address and send Binding Updates to
their Home Agent as well as their Correspondent Nodes. Again it
is evident that route optimization is achieved by these nodes
using a reduced number of signaling messages with external
routers as the Mobile Router plays the role of an Access Router
for the nodes within the mobile network. It is also evident that
optimal routing for nodes behind the Mobile Router is achieved
without requiring any changes to the standard MIPv6 operation of
these nodes as well as their Correspondent Nodes.
The NEMO-enabled nodes can opt to dynamically configure the
Mobile Router to be their Home Agent. This process will be
explained in Section 5. In this case these nodes need only to
send a Binding Update to the Mobile Router and the Mobile Router
will perform the duties of a MIPv6 Home Agent for these nodes.
NEMO-enabled nodes can perform route optimization as a standard
MIPv6 node once they dynamically configure the Mobile Router to
be their Home Agent.
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4. Mobile Router Operations
In Section 4.1 we provide the details of operations a Mobile Router
needs to perform when playing the role of an Access Router. This is
followed by a description of operations a Mobile Router performs as a
Home Agent in Section 4.2.
4.1 Mobile Router Operations as an Access Router
The Mobile Router would obtain a prefix from the Access Router in
the visited network operating as a standard MIPv6 node. This is
performed by running a prefix delegation protocol such as DHCPv6
[5]. (Details of this is beyond the scope of this document) After
obtaining the prefix the Mobile Router would advertise this prefix
to the nodes behind the Mobile Router. This can be done by using
Router Advertisements as described in RFC 2461 [6] with no
extensions.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cur Hop Limit |M|O| Reserved | Router Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reachable Time |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Retrans Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ...
+-+-+-+-+-+-+-+-+-+-+-+-
Figure 4: Router Advertisement Message Format
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4.2 Mobile Router operations as a Home Agent
In this section we describe the operations a Mobile Router needs to
perform when it is capable of playing the role of an Home Agent.
4.2.1 Process of Discovering the Mobile Router
If the Mobile Router is capable of playing the role of a Home
Agent we propose to extend the above Router Advertisement
message format by introducing a new flag bit R. This is to
indicate to the NEMO-enabled nodes that the Router sending the
Advertisements is a Mobile Router. The receivers which do not
understand this flag MUST ignore it. We also introduce a new
option named 'Home Link' to specify the Mobile Router's home
link prefix. This option assists the NEMO-enabled nodes to
determine whether they belong to the same link as the Mobile
Router. If the prefix advertised on the 'Home Link' option
matches the home address prefix of any of the NEMO-enabled
nodes, these nodes can opt to reconfigure the Mobile Router as
their Home Agent.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cur Hop Limit |M|O|R| Reserved| Router Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reachable Time |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Retrans Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ...
+-+-+-+-+-+-+-+-+-+-+-+-
Figure 5: Router Advertisement Message Format
This format represents the following changes over that
originally specified in RFC 2461 [6]:
Mobile Router Bit(R)-
The Mobile Router (R) bit MUST be set to 1 in the Router
Advertisement sent by the Mobile Router while the Mobile Router
is attached to a foreign link.
Reserved Field -
The Reserved Field changed from 6 bits to 5 bits.
Options -
Home Link :
This option specifies the Mobile Router's home link prefix.
Receivers MUST ignore any options they do not recognize and
continue processing the message [6].
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4.2.2 Establishment of a Bidirectional Tunnel between the Mobile
Router and the NEMO-enabled nodes
The nodes which opts to use the Mobile Router as the Home Agent
would send Binding Updates to the Mobile Router. If the Binding
update is valid that is if the message is from a node that
belongs to the Mobile Router's home network, the Mobile Router
would send a Binding Acknowledgement to the sending node. This
process would establish a bidirectional tunnel between the
Mobile Router and these nodes. The binding messages exchanged
here are in the same format as standard MIPv6.
4.2.3 Establishment of a Bidirectional Tunnel between the Mobile
Router and its Home Agent
The Mobile Router would send a Binding Update to its Home Agent
indicating that its behaving as a Mobile Router and not a
Mobile Node. This can be done by employing the Binding Update
format used in the NEMO basic protocol [1]. A new flag bit,
Mobile Router flag(R) is used in [1]. When this flag is set the
the Home Agent forwards packets destined to the mobile network
to the Mobile Router. We propose to use the new mobility
options defined in [1] in addition to what is defined in [2] in
order to adhere with the NEMO basic protocol. These options are
not described on this document, for details refer Section 4.1
in [1]. Figure 5 illustrates the new Binding Update format.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A|H|L|K|R| Reserved | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6 : Format of Binding Update with new Mobile
Router Flag bit (R)
Mobile Router Flag (R)
The Mobile Router Flag is set to indicate to the Home Agent
that the Binding Update is from a Mobile Router. If the flag
is set to 0, the Home Agent assumes that the Mobile Router is
just behaving as a Mobile Node, and should not forward packets
destined for the mobile network to the Mobile Router.
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5. Mobile Router's Home Agent Operations
On receiving a Binding Update with the Mobile Router flag bit (R) set
the Home Agent of the mobile network would place it in its binding
cache. When a packet arrives at the home network the Home Agent would
intercept the packet and would look up the binding cache with a
longest prefix matching algorithm. We advocate on the use of such an
algorithm at the Home Agent in order to accommodate Local Mobile
Nodes being away from the home network as well as not being in the
mobile network. Figure 6 below depicts such a scenario. Use of such
an algorithm would also accommodate nodes which are not NEMO-enabled
but are MIPv6 capable. If the Home Agent has a Binding Update for a
full address or a longer prefix than the mobile network's prefix it
would be routed to the care-of address on this Binding Update.
____ ____ ____ ____
| | | | | | | |
| CN | | CN | | CN | | CN |
|____| |____| |____| |____|
_____|_______________|____________|_____________|______
| |
| |
| Internet |
| |
|_______________________________________________________|
__|_ __|_ __|_
| | Access | | | |
| AR | Router | AR | | AR |
|____| |____| |____|
______|__ Foreign _____|___ Home ______|___ Foreign
_|__ Link __|_ Link _|___ Link
| | | | | |
| MR | | HA | | LMN |
|____| |____| |_____|
|
_____|______________________
__|__ __|__ __|__
| | | | | |
| VMN | | LMN | | LFN |
|_____| |_____| |_____|
Figure 7: Local Mobile Node away from the Home Network and Mobile
Network
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6. Mobile Network Nodes Route Optimization Operations
6.1 MIPv6-enabled Mobile Network Nodes Operations
These nodes would obtain the new access network prefix from the
Router Advertisement messages sent by the Mobile Router, which
enables them to auto configure a topologically correct address.
Each of them having their own care-of address can operate as
standard MIPv6 nodes and enable route optimization.
6.2 Operations specific to NEMO-enabled Nodes
We define any NEMO-enabled node to be capable of dynamically
reconfiguring its Home Agent to be the Mobile Router. These nodes
upon receiving Router Advertisements with the Mobile Router Flag
(R) set can choose to make the Mobile Router to be their Home
Agent. After reconfiguring the Mobile Router to be their Home Agent
these nodes need not perform any other network mobility related
operations. These nodes are then able to achieve route optimization
by following the standard MIPv6 protocol while needing to only
communicate with a Home Agent that resides locally. Since the
Mobile Router plays the role of a standard MIPv6 Home Agent for
these nodes this hierarchical Home Agent structure is hidden from
the NEMO-enabled nodes.
7. Security Considerations
The Mobile Network Nodes having their own care-of address can perform
the return routability procedure [2] as standard MIPv6 nodes. When
the Mobile Router is sending a Binding Update representing the
NEMO-enabled nodes sitting behind it, it is necessary that the Home
Agent verifies that these Binding Updates belong to the Mobile
Network. This does not add any security consideration other than what
is described in NEMO basic protocol [1].
Acknowledgements
This work was carried out through an Australian Research Council Linkage
Postgraduate Research Award with Vodafone Australia Future Technologies.
References
[1] V. Devarapalli, R. Wakikawa, A. Petrescu and P. Thubert. Nemo
Basic Support Protocol (work in progress), Internet Draft,
IETF. draft-ietf-nemo-basic-support-00.txt, June 2003
[2] D. Johnson, C. Perkins and J. Arkko. Mobility Support in IPv6 (work
in progress),Internet Draft, IETF, draft-ietf-mobileip-ipv6-22.txt.
May 2003
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[4] J. Manner and M. Kojo, "Mobility Related Terminology", (work in
progress), draft-ietf-seamoby-mobility-terminology.txt, Internet
Draft, IETF, April 2003
[5] Thomson, S. and T. Narten, "IPv6 Stateless Address
Autoconfiguration", RFC 2462, December 1998
[6] Droms, R., "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)",
draft-ietf-dhc-dhcpv6-28 (work in progress), November 2002.
[7] T. Narten, E. Nordmark and W. Simpson. Neighbour Discovery for IP
Version 6 (IPv6), RFC 2461, IETF, December 1998
Author's Addresses :
Eranga Perera
University of New South Wales
Department of Electrical Engineering and Telecommunications
Sydney,
NSW 2052,
Australia
Email : eranga@mobqos.ee.unsw.edu.au
Robert Hsieh
University of New South Wales
Department of Electrical Engineering and Telecommunications
Sydney,
NSW 2052,
Australia
Email : roberth@ee.unsw.edu.au
Aruna Seneviratne
University of New South Wales
Department of Electrical Engineering and Telecommunications
Sydney,
NSW 2052,
Australia
Email : a.seneviratne@unsw.edu.au
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