MANET Autoconfiguration (AUTOCONF) I. Chakeres
Internet-Draft Boeing
Intended status: Informational J. Macker
Expires: September 3, 2007 Naval Research Laboratory
T. Clausen
LIX, Ecole Polytechnique
March 2, 2007
Mobile Ad hoc Network Architecture
draft-ietf-autoconf-manetarch-01
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Abstract
This document discusses Mobile Ad hoc NETworks (MANETs). It
introduces basic MANET terms, characteristics, and challenges. This
document also defines several MANET entities and architectural
concepts.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Borrowed Terminology . . . . . . . . . . . . . . . . . . . 3
2.2. MANET Terminology . . . . . . . . . . . . . . . . . . . . 5
3. MANET Motivation Discussion . . . . . . . . . . . . . . . . . 6
4. MANET Interface Characteristics . . . . . . . . . . . . . . . 7
4.1. Qualities - Wireless, Mobile, Ad hoc . . . . . . . . . . . 7
4.2. Challenges . . . . . . . . . . . . . . . . . . . . . . . . 8
4.2.1. Semi-Broadcast Interface . . . . . . . . . . . . . . . 8
4.2.2. Fuzzy Neighbor Relationship & Extended Neighborhood . 9
4.2.3. MANET Membership . . . . . . . . . . . . . . . . . . . 9
5. Addressing, aka the MANET Prefix Model . . . . . . . . . . . . 10
6. MANETs' Place in the Network Stack . . . . . . . . . . . . . . 13
7. Cross Layering . . . . . . . . . . . . . . . . . . . . . . . . 14
8. Deployment Taxonomy . . . . . . . . . . . . . . . . . . . . . 15
8.1. Service Availability . . . . . . . . . . . . . . . . . . . 15
8.2. Number of Peer MANET Routers . . . . . . . . . . . . . . . 15
8.3. Example Deployments . . . . . . . . . . . . . . . . . . . 16
9. Security Considerations . . . . . . . . . . . . . . . . . . . 16
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
12. Informative References . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
Intellectual Property and Copyright Statements . . . . . . . . . . 20
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1. Introduction
A Mobile Ad hoc NETwork (MANET) consists of a loosely connected set
of MANET nodes. Each MANET node embodies a MANET router and zero or
more hosts. These routers organize and maintain a routing structure
among themselves. These routers usually communicate over wireless
links and may be mobile. MANETs' characteristics create challenges
in several areas, and often require protocol extensions or new MANET
protocols altogether.
This document is focused on IP networking, though many of MANETs'
concepts and issues span the protocol stack.
This document is meant to complement [RFC2501] in describing and
defining MANET.
2. Terminology
2.1. Borrowed Terminology
Much of the terminology in this document was borrowed from existing
documents, to list a few [RFC1812], [RFC2328], [RFC2453], [RFC2460],
[RFC2461], [RFC3513], [RFC3753], [I-D.iab-multilink-subnet-issues],
[I-D.templin-autoconf-dhcp], and [I-D.ietf-ipv6-2461bis]. Note that
the original text for the terms is often modified, though we have
attempted to maintain the same meaning. In the future, terms defined
elsewhere will likely be cited instead of included.
This document employs the following definitions:
Node
any device (router or host) that implements IP.
Router (RT)
a node that forwards IP packets not explicitly addressed to
itself.
Host
any node that is not a router, i.e. it does not forward packets
addressed to others.
Link
A communications facility at a layer below IP, over which nodes
exchange IP packets directly without decrementing IP TTL (Hop
Limit).
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Asymmetric Reachability
A link where non-reflexive and/or non-transitive reachability is
part of normal operation. Non-reflexive reachability means
packets from X reach Y but packets from Y don't reach X. Non-
transitive reachability means packets from X reach Y, and packets
from Y reach Z, but packets from X don't reach Z. Many radio/
wireless interfaces exhibit these properties.
Neighbor
If node X can directly exchange IP packets with node Y, then node
Y is node X's neighbor. Packet reception characteristics are
often used to assist devices in determining the quality of
neighbors' communication.
Interface
A node's point of attachment to a communication link.
Broadcast Interface
An interface supporting many attached nodes, together with the
capability to address a single link layer message to all of the
attached nodes (broadcast). The set of nodes receiving a given
physical broadcast message are the neighbors of the node
originating the message.
Full-Broadcast Interface (FBI)
A broadcast interface with reflexive and transitive reachability.
All nodes on the interface can send and receive IP packets
directly, all nodes are symmetric neighbors. An Ethernet segment
is an example of a FBI.
Semi-Broadcast Interface (SBI)
A broadcast interface that may exhibit non-reflexive and/or non-
transitive reachability. A FBI is a special case of SBI.
Multiple access wireless radio interfaces are often SBI.
Site
a set of one or more links.
Flooding
The process of forwarding or distributing information to all
devices with in a bounded region.
Border Router (MBR)
a router that participates in multiple routing regions, and often
multiple routing protocols. A BR forms a border between its
multiple routing regions. A BR is responsible for presenting a
consistent picture of the nodes reachable through itself to each
routing region. A BR determines the routing information to
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propagate between different routing regions.
2.2. MANET Terminology
In MANET there are two important entities. We define the following
entities:
MANET Node (MN)
a MANET node embodies a MANET router and zero or more hosts, as
illustrated in Figure 1.
MANET Router (MR)
an entity that has one or more MANET interfaces and that engages
in a MANET routing protocol. A MANET router may also have zero or
more classic IP interfaces to which hosts may connect.
<~~~~~~+~~~~~~> MANET
| INTERFACE
''''''''''|''''''''''
' +-------|------+ '
' | MANET Router | '
' +-------+-+----+ '
' : : '
' MANET : +---+ '
' Node : | H | ' ============
' : +---+ ' = : =
'''''''''':'''''''''' =CLASSIC IP=
+......+......+ =INTERFACES=
: : ============
+-+-+ +-+-+
| H | * * * | H |
+---+ +---+
Figure 1: MANET Node
In MANET there are several architectural scopes. We define the
following scopes:
MANET Neighbors
a set of MANET routers that is reachable in one hop over MANET
interface(s).
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MANET N-Neighborhood
a set of MANET routers that is reachable in a N hops. These
routers usually have a large number of common neighbors and may
directly compete for the same shared wireless resources.
MANET
a set of MANET routers that is reachable via one or more hops.
If a link forms between two previously separated MANET routers or
MANETs, the two MANETs will merge to form a single larger MANET.
Similarly, if a critical link between two MANET routers is lost the
MANET will partition into two MANETs.
When discussing MANETs' connectivity to other networks, like the
Internet, a MANET is bounded by border routers (BR). That is, a
MANETs' BR form a border between a MANET and other routing regions.
3. MANET Motivation Discussion
The Internet Protocol (IP) core design tenets -- connectionless
networking and packet-based forwarding -- are ideally suited for use
in highly dynamic contexts, such as MANETs. Yet, some additional
functionality is required to meet the unique challenges and
opportunities present in MANETs.
The initial motivation for MANETs was called Packet Radio (PR)
networking [FL01]. In PR, each router is equipped with a single SBI.
This configuration is the simplest MANET router configuration. Each
router may be mobile, and the routers may be or may become spatially
distributed such that all routers cannot communicate directly. That
is, two routers might require one or more other intermediate routers
to forward (route) packets on their behalf. In the example shown in
Figure 2, for RT1 to send packets to RT3, the intermediary RT2 must
relay the packets. This implies that RT2 must receive the packet
from RT1 on its interface and determine that it must retransmit the
packet over the same interface as the one where the packet was
received, in order for the packet to reach RT3. This example also
illustrates how SBIs differ from FBIs: from the point of view of RT2,
both RT1 and RT3 are neighbors, whereas RT1 and RT3 are not
themselves neighbors with one another.
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Communication
Range
<~~~~~~+~~~~~~> <~~~~~~+~~~~~~>
Single | <~~~~~~+~~~~~~> |
SBI +-|-+ +-|-+ +-|-+
|RT1| |RT2| |RT3|
+---+ +---+ +---+
Figure 2: Basic MANET Network
In addition to addressing nodes' asymmetric reachability other
challenges exist. In PR networks, shared wireless resources result
in interdependence between nearby nodes, and these nodes often
communicate directly or indirectly. The dynamic wireless interface
characteristics and node mobility often manifest as frequent network
topology changes.
PR networks also lead to several other architecture related
challenges. One challenge was to attach these PR networks to other
networks, especially fixed networks like the ARPANET. Another
related challenge was how to deal with the large disparity between
different node and interface characteristics.
These PR network challenges helped stimulate the Internet Protocol;
an architecture based on connectionless networking and packet-based
forwarding that enables interconnection of heterogeneous devices over
heterogeneous interfaces.
4. MANET Interface Characteristics
Inheriting from Packet Radio as described above, a chief
particularity of MANETs are the characteristics and qualities of
MANET interfaces, and the challenges these entail for protocol design
and development.
4.1. Qualities - Wireless, Mobile, Ad hoc
In MANET several qualities impact protocol design. The most
fundamental qualities are wireless interface characteristics,
mobility, and ad hoc interaction.
Wireless interfaces exhibit challenging characteristics when compared
with wired interfaces. Many protocols (e.g. neighbor discovery) do
not operate in wireless networks with asymmetric reachability.
Wireless interfaces also exhibit time varying performance that can
significantly impact local communication.
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Mobility can also exacerbates wireless networking issues, making it
more challenging to attain, establish, and maintain network neighbor
relationships between nodes.
Ad hoc networking further compounds problems by allowing nodes to
join and leave the network, or even form new networks, at will.
4.2. Challenges
MANETs characteristics result in many challenges. These challenges
reveal themselves in many forms, and MANET specific protocols must
often be developed.
4.2.1. Semi-Broadcast Interface
Given a wireless SBI (with non-transitive and non-reflexive
properties) and spatially distributed nodes, each node may have a
different unique partial view of the MANET. That is, each node may
have a different set of adjacent nodes.
Communication
Range
<~~~~~~+~~~~~~> <~~~~~~+~~~~~~>
Single | <~~~~~~+~~~~~~> |
SBI +-|-+ +-|-+ +-|-+
|RT1| |RT2| |RT3|
+---+ +---+ +---+
RT1 RT2 RT3
-------------------------
Neighbors * RT2 RT1 RT2
* RT3
Figure 3: Semi-Broadcast Interface (SBI) Neighbors
The possibly unique set of adjacent nodes in each node often requires
nodes to forward packets out the same wireless interface as the one
over which they were received. Topologically, this act of forwarding
out the same interface causes a packet to reach a possibly different
set of nodes by traversing the wireless communication medium in a new
location. An example is provided in Figure 3, where each router is
capable of reaching a different set of routers.
The act of forwarding packets out of the same interface as the one
over which they were received often results in duplicate IP packets
being received at nodes with more than one neighbor, while also
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reaching a new subset of nodes.
4.2.2. Fuzzy Neighbor Relationship & Extended Neighborhood
Defining the process of determining a neighbor's existence, continued
existence, and loss of existence is a fundamental challenge in
MANETs. Neighbors are hard to define due to the expected interface
characteristics: non-transitive, non-reflexive, time varying, and
other wireless properties.
Historically, two nodes are either neighbors or not neighbors and
several simple mechanisms have been used to determine a neighbor
relationship: single packet reception, acceptable loss rates, and
simple handshakes. In wireless networks the types of neighbor
relationships expand, as do the mechanisms to detect and maintain the
state of such relationships.
In wireless networks, nodes may often have non-reflexive (also often
seen called unidirectional or asymmetric) communication links.
Wireless networks also experience significant time varying packet
delivery, so simple loss rates may not be sufficient to define a
neighbor relationship. Similarly, as nodes move relatively to each
other, past loss rates may not reflect future communication
capabilities.
In wireless systems, nodes within the same small geographic region
are often densely connected with other nodes in the same region.
These nodes form a set of extended neighbor relationships that is
referred to as a neighborhood. A neighborhood is typically composed
of several nodes, with each node being densely connected to other
nodes.
These more dynamic neighbor relationships do not sit well with
certain Internet Protocols designed assuming an fixed Ethernet like
model to communication links (reflexive, transitive, and stable).
Given the unknown neighbor relationships, the addressing model often
associated with a Ethernet link is not valid. For example, in an
Ethernet network routers are often told that a particular range of
addresses are directly reachable. In MANETs' a node often cannot
make assumptions that a particular set of addressable nodes is always
reachable. Instead, nodes must detect and determine their neighbors,
and handle the changes to their neighbors over time.
4.2.3. MANET Membership
Given MANETs' characteristics (mobile, wireless, ad hoc), determining
a MANETs' membership is difficult, if not impossible in certain
scenarios.
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/----------------------\ /----------------------\
| MANET | | MANET |
| +---+ +---+ +---+ | | +---+ +---+ +---+ |
| |MN1+-+MN2+-+MN3| | | |MN1+-+MN2+-+MN3| |
| +-+-+ +---+ +---+ | | +---+ +---+ +-+-+ |
| | | | | |
| +-+-+ | Change | +-+-+ |
| |MN4+ | in | |MN7| |
| +---+\ | Time | +---+ |
| \+---+ | \----------------------/
| +MN5+ | /----------------------\
| /+---+\ | | MANET |
| +---+/ \+---+ | | +---+ +---+ +---+ |
| |MN6+ +MN7| | | |MN6+--+MN4+--+MN5| |
| +---+ +---+ | | +---+ +---+ +---+ |
\----------------------/ \----------------------/
Figure 4: MANET(s)
At one moment a MANET might consist of a certain set of nodes, and
the next the MANET could partition into several MANETs. Later it
might re-merge or merge with a new set of nodes and form a larger
MANET.
To assist in coordinating among a loosely connected set of MANET
routers, a procedure called flooding is used. MANET flooding consist
of disseminating a packet to all connected MANET routers.
Certain routers in a MANET might connect to other routing regions.
These routers are called MANET Border Routers (MBR), and they often
run multiple routing protocol instances. The MBR are responsible for
choosing the routing information to share between the various
attached routing regions. The MBR should also present a consistent
picture of the nodes reachable through them.
As MANET membership changes, so does the connectivity of MBR within
the MANET. Therefore, a MBR may be challenged to present a
consistent set of reachable nodes. It may even choose not to share
routing information about the MANET topology to other routing
regions.
5. Addressing, aka the MANET Prefix Model
This section presents an architectural model for MANETs which
preserves the integrity of the IP architecture while allowing for the
particularities of MANETs.
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This architectural model considers MANET nodes as routers with hosts
attached, as illustrated in Figure 5. These attached hosts may be
"external" (i.e. attached to the router via other network interfaces)
or "internal" - however the important observation to make is, that
the links between these hosts and the router are classic IP links.
This fact implies that, from the point of view of the hosts and the
applications running on these hosts, connectivity is via a classic IP
link. Hosts and their applications are not exposed to the specific
characteristics of the MANET interfaces and are connected to the
MANET via a router, which has one or more MANET interfaces.
<~~~~~~+~~~~~~> MANET <~~~~~~+~~~~~~>
| INTERFACE |
''''''''''|'''''''''' ''''''''''|''''''''''
' +-|-+ MANET ' ' MANET +-|-+ '
' | R | Node ' ' Node | R | '
' +-+-+ ' ' +-+-+ '
' : : ' ' : : '
' : +---+ ' ' : +---+ '
' : | H | ' ============ ' : | H | '
' : +---+ ' = : = ' : +---+ '
'''''''''':'''''''''' =CLASSIC IP= ' : '
+......+......+ =INTERFACES= ' +......+......+ '
: : ============ ' : : '
+-+-+ +-+-+ '+-+-+ +-+-+'
| H | * * * | H | '| H | * * * | H |'
+---+ +---+ '+---+ +---+'
'''''''''''''''''''''
Figure 5: MANET Addressing Model
If the MANET router is delegated a prefix p::, this prefix can be
assigned to the classic IP link(s), and hosts can be assigned
addresses from within this prefix, and configured with this prefix as
illustrated in Figure 6. Specifically, the MANET interface(s) of the
router are *not* configured with this prefix. The configuration of
MANET interfaces is detailed below.
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MANET <~~~~~~+~~~~~~>
INTERFACE | ASSIGNED
''''''''''|'''''''''' PREFIXES
' MANET +-|-+ ' =========
' Node | R | ' <=== P:: =
' +-+-+ ' =========
' : : '
' : +---+ ' =========
============ ' : | H | ' <=== P:1:: =
= : = ' : +---+ ' =========
=CLASSIC IP= ' : '
=INTERFACES= ' +......+......+ '
============ ' : : '
'+-+-+ +-+-+' =========
'| H | * * * | H |' <=== P:2:: =
'+---+ +---+' =========
'P:2::1 P:2::N'
'''''''''''''''''''''
Figure 6: MANET Node and Prefixes
MANET specific behaviors are exclusively exposed to the MANET
interface(s) of the routers. This includes MANET routing protocols
and interface and link characteristics (asymmetric neighborhoods,
semi-broadcast interfaces, fuzzy neighbor relationships, topology
dynamics, etc.).
The following characteristics deserve particular mention, since they
distinguish MANET interfaces and the MANET link model from the
classic IP link model:
Unique Prefixes
MANET interfaces must be configured with unique prefixes, that is
so that no two MANET interfaces are configured to appear within
the same IP prefix. Some common ways to achieve this are:
* unnumbered interfaces (IPv4) [RFC1812];
* link-local addresses (IPv6);
* /128 (IPv6) or /32 (IPv4) prefixes.
However it is worth noting that prefix lengths shorter than /128
(IPv6) or /32 (IPv4) are possible on the MANET interfaces, as long
as the prefixes are unique to a single MANET interface.
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Link-local Multicast/Broadcast Scope
On a MANET interface, a link-local multicast or broadcast reaches
MANET interfaces of neighboring nodes, regardless of their
configured addresses. A link-local multicast or broadcast on a
MANET interfaces is a "neighborcast" and is not forwarded, nor is
it assumed to be received by all nodes within a MANET.
The MANET addressing model presented in this section makes a clear
separation between the role of router and host in a MANET,
recognizing that:
o MANET interfaces are seen only by the router, assumed to be MANET
aware, and running appropriate protocols;
o MANET interfaces forming a multihop MANET area may use a site
prefix;
o hosts and subnets on a non-MANET interface assume a classic IP
link model;
o applications on hosts and protocols assuming classic IP interfaces
run unmodified.
MANET protocols are developed to work on MANET interfaces. The MANET
WG is chartered to develop routing protocols for MANET interfaces.
The Autoconf WG is chartered to develop autoconfiguration protocols
for MANET interfaces and MANET routers.
6. MANETs' Place in the Network Stack
While the MANET WG is focused upon network (L3) routing, that does
not imply that MANETs and their protocols are limited to L3. Several
previous and existing efforts are applying MANET protocols at various
layers. The challenges discussed above, exist independent of at
which layer MANET protocols are deployed. Of course, the protocols
themselves may need to be retooled slightly to accommodate the
information available to the deployed layer.
MANET MAC layer (L2) routing, more often called bridging, may work in
homogeneous wireless networks for delivering frames over multiple
hops. One example of L2 MANET is being developed in the IEEE 802.11s
effort.
L2 routing/bridging hides the multiple L2 hops from L3. This
behavior can be advantageous as this network can transparently mimic
an Ethernet, to some extent. The ability to mimic Ethernet allows
the L2 MANET to utilize existing L3 network protocols.
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Alternatively, this transparency may lead to performance problems.
For example, if the L3 protocols make heavy use of broadcast
messaging or devices assume that high-speed wired bandwidth resources
are available.
L2 MANET does not enable heterogeneity. That is, L2 MANET is not
capable of bridging across heterogeneous interfaces. For example, L2
bridging cannot directly bridge two L2 technologies with different
addressing schemes. It can also be difficult if the frame sizes of
two L2 vary, as this could require breaking a single frame into
multiple frames of a different format.
L3 MANET enables heterogeneous networking, as IP was built with this
feature in mind. Forming a MANET at L3 implies that the L3 protocols
must handle the challenges presented in this document.
MANET like protocols can also be used at higher layers. One example
is peer-to-peer (P2P) networks. These networks have some of the same
challenges as MANET, e.g. variable neighbor relationships and
changing membership.
7. Cross Layering
In wireless networks, and especially in MANET, extended interfacing
among the network layers (physical, MAC, link, network, etc.) can be
extremely useful. Arguably, for MANET deployments to be successful,
some degree of cross layering should be considered. For example,
link layer feedback that a packet/frame was not able to be sent or
that it was not received could be used by the network layer to
indicate that a neighbor is no longer reachable. This information
and other extended interfacing could reduce, or eliminate, some upper
layer messaging. Further, it could significantly reduce the latency
in decision making. Note that though a certain lower layer
information is valuable, it likely needs to be extrapolated or
filtered before accurate assumptions about the network state can be
made. For example, failure to deliver a frame by itself may not be a
good indicator that a node is or is not reachable.
In networks with several different layers of MANET mechanism, the
sharing of information across different layers can be even more vital
to creating and maintaining the network. For example, if a P2P
network is run on top of a L3 MANET, the two networks can share
information to use a similar optimized topology. Similarly, they
could share neighbor state changes to reduce the messaging or latency
in making decisions.
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8. Deployment Taxonomy
The present and future proliferation of inexpensive wireless
interfaces continues to stimulate technical interest and developments
in the area of MANET for a wide variety of deployment scenarios. In
this section, we present several characteristics for describing
expected MANET deployments.
8.1. Service Availability
Nodes often expect certain services/servers to be available. When
describing a deployment scenario, it is important to specify the
expected services available and the distance between the
participating devices. In MANET, nodes might assume a service is
available locally (within one IP hop) or within a particular scope
(one or more IP hops - MANET, site, global). Nodes might assume in
certain deployments that no special servers/services are available.
Finally, nodes might assume that servers are sometimes available, but
their availability is not guaranteed or ensured.
Different frameworks for autoconfiguration, network management, and
intra-AS routing can be developed based upon the expected constraints
and operating conditions.
8.2. Number of Peer MANET Routers
The number of peer MRs in a MANET is an important consideration.
This number is not the complete number of nodes in a MANET (since MRs
may support an arbitrary number of connected nodes) but a measure of
the number of MR participating as a cohesive flat routing area. That
is, the number of MR within a single routing region.
While the number of peer MRs does not define scalability of a MANET
protocol, it is often useful to discuss the number of peer MR to get
a feel for maturity of typical deployment solutions. For simplicity
we define the following network sizes to aid in discussion:
Small
2-30 MR peers
Moderate
30-100 MR peers
Large
100-1000 MR peers
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Very large
Larger than 1000 MR peers
At the time of writing, small and moderate size peer MANET routing
scenarios have matured and have reasonable testing and deployment
experience. These sizes can perform reasonably well in many cases
without hierarchy. MANET architectures can, of course, support
routing hierarchies to improve scaling. Large and very large MANET
routing areas that are flat are still a topic of active research and
are not considered here. One can apply hierarchy to achieve scaling,
but again that is not being discussed here. Existing MANET routing
developments, such as SMF [I-D.ietf-manet-smf], have shown
significant performance improvements and capabilities even in small
peer router size deployments and experiments using classical routing
designs.
8.3. Example Deployments
Here we provide a short list of example deployment scenarios:
Home, office, campus, and community mesh networks
Disaster relief and first responder networks
Sensor networks
Range extension
Military communications
Automotive networks
9. Security Considerations
TBD
10. IANA Considerations
This is an informational document. IANA requirements for MANET
related protocols will be developed within the protocol
specifications for MANET protocols.
11. Acknowledgments
Discussions and developments concepts and architectural issues have
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evolved over many years of discussion of related work within the
MANET WG. There are obviously many people that have contributed to
past discussions and related draft documents within the WG that have
influenced the development of these concepts that deserve
acknowledgment. The authors would like to thank all contributors to
the MANET and AUTOCONF WG efforts and those that have helped in the
review and content process.
While not entirely complete the authors would like to in
particular thank the following individuals for there discussions
and contributions:
Jari Akko
Emmanuel Baccelli
Justin Dean
Christopher Dearlove
Tom Henderson
Bob Hinden
Thomas Narten
Charles Perkins
Subhranshu Singh
Fred Templin
Dave Thaler
Seung Yi
12. Informative References
[DWN03] Macker, J. and S. Corson, "Mobile Ad hoc Networking:
Routing Technology for Dynamic, Wireless Networks", IEEE
Press, Mobile Ad hoc Networking, Chapter 9, 2003.
[FL01] Freebersyser, J. and B. Leiner, "A DoD perspective on
mobile ad hoc networks", Addison Wesley C. E. Perkin, Ed.,
2001, pp. 29--51, July 2001.
[I-D.iab-multilink-subnet-issues]
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Internet-Draft MANET Architecture March 2007
Thaler, D., "Multilink Subnet Issues",
draft-iab-multilink-subnet-issues-03 (work in progress),
January 2007.
[I-D.ietf-ipv6-2461bis]
Narten, T., "Neighbor Discovery for IP version 6 (IPv6)",
draft-ietf-ipv6-2461bis-10 (work in progress),
January 2007.
[I-D.ietf-manet-smf]
Macker, J., "Simplified Multicast Forwarding for MANET",
draft-ietf-manet-smf-03 (work in progress), October 2006.
[I-D.templin-autoconf-dhcp]
Templin, F., "MANET Autoconfiguration",
draft-templin-autoconf-dhcp-06 (work in progress),
February 2007.
[RFC1812] Baker, F., "Requirements for IP Version 4 Routers",
RFC 1812, June 1995.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC2453] Malkin, G., "RIP Version 2", STD 56, RFC 2453,
November 1998.
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, December 1998.
[RFC2461] Narten, T., Nordmark, E., and W. Simpson, "Neighbor
Discovery for IP Version 6 (IPv6)", RFC 2461,
December 1998.
[RFC2501] Corson, M. and J. Macker, "Mobile Ad hoc Networking
(MANET): Routing Protocol Performance Issues and
Evaluation Considerations", RFC 2501, January 1999.
[RFC3513] Hinden, R. and S. Deering, "Internet Protocol Version 6
(IPv6) Addressing Architecture", RFC 3513, April 2003.
[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.
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Authors' Addresses
Ian Chakeres
Boeing
The Boeing Company
P.O. Box 3707 Mailcode 7L-49
Seattle, WA 98124-2207
USA
Email: ian.chakeres@gmail.com
Joe Macker
Naval Research Laboratory
Washington, DC 20375
USA
Email: macker@itd.nrl.navy.mil
Thomas Heide Clausen
LIX, Ecole Polytechnique
91128 Palaiseau CEDEX
France
Email: T.Clausen@computer.org
URI: http://www.lix.polytechnique.fr/Labo/Thomas.Clausen/
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