MANET Autoconfiguration (AUTOCONF) I. Chakeres
Internet-Draft Motorola
Intended status: Informational J. Macker
Expires: December 2, 2007 Naval Research Laboratory
T. Clausen
LIX, Ecole Polytechnique
May 31, 2007
Mobile Ad hoc Network Architecture
draft-ietf-autoconf-manetarch-02
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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 . . . . . . . . . . . . . . . . . . . 10
5. Addressing & the MANET Prefix Model . . . . . . . . . . . . . 11
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 . . . . . . . . . . . . . . . . . . . . . 17
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 17
12. Informative References . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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 routers. Each MANET router embodies routing/forwarding
functionality and may also incorporate host functionality. These
routers organize and maintain a routing structure among themselves.
These routers may communicate over wireless links with asymmetric
reachability, may be mobile, and may join and leave the network at
any time. 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
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.
2.1. Borrowed Terminology
This document employs the following definitions:
Node (N)
any device (router or host) that implements IP.
Router (R)
a node that forwards IP packets not explicitly addressed to
itself.
Host (H)
any node that is not a router, i.e. a host 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 that
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 (BR)
a router that participates in multiple routing regions, and often
multiple routing protocols. A BR defines the 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
We define the following MANET entity:
MANET Router (MAN)
a MANET router embodies router functionality and may also
incorporate an internally addressable host (IAH) logic, as
illustrated in Figure 1. A MANET router has one or more
interfaces. To simplify discussion we will classify the
interfaces into two categories: classic IP interfaces & MANET
interfaces. MANET interfaces are defined as interfaces that
demonstrate asymmetric reachability and/or neighbor addresses that
are not known a priori. A MANET router may participate in routing
on zero or more MANET interfaces. A MANET router may participate
in routing on zero or more classic IP interfaces. A MANET router
may also have zero or more classic IP interfaces to which other
nodes may connect; i.e. the router may be responsible for several
IP prefixes.
<~~~~~~+~~~~~~> Routing-MANET
| Interface(s)
''''''''''|'''''''''''''''''
' +-------|--------------+ '
' | Router Functionality |...................
' +-------+-+------------+ ' Routing-Classic
' : : ' IP Interface(s)
' MANET : +-----------+ '
' Router : | Internal | '
' : |Addressable| '
' : |Host Logic | '
' : | (IAH) | '
' : +-----------+ '
'''''''''':'''''''''''''''''
: Nodes that live behind the router
+......+.........+ ============
: : = : =
+-+-+ +----+----+ =CLASSIC IP=
| N | * * * | Node(s) | =INTERFACES=
+---+ +---------+ ============
Figure 1: MANET Router
In MANETs there are several architectural scopes. We define the
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following scopes:
MANET Neighbors
a set of MANET routers that is reachable via one IP hop, reachable
via link-local messaging.
MANET N-Neighborhood
a set of MANET routers that is reachable via N-hops. These
routers usually have a large number of common neighbors and may
directly compete for the same shared wireless resources.
MANET
a routing region consisting of a set of MANET routers that is
reachable via one or more MANET router hops. If a MANET connects
to other routing regions, its border is defined by Border Routers.
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, then
the MANET will be partitioned into two MANETs.
When discussing MANETs' connectivity to other networks, such as 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 R1 to send packets to R3, the intermediary R2 must
relay the packets. This implies that R2 must receive the packet from
R1 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 R3. This example also illustrates how
SBIs differ from FBIs: from the point of view of R2, both R1 and R3
are neighbors, whereas R1 and R3 are not themselves neighbors with
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one another.
Communication
Range
<~~~~~~+~~~~~~> <~~~~~~+~~~~~~>
Single | <~~~~~~+~~~~~~> |
SBI +-|-+ +-|-+ +-|-+
| R1| | R2| | R3|
+---+ +---+ +---+
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, chief
particularities 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
to wired interfaces. Many protocols (e.g. neighbor discovery) do not
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operate in wireless networks with asymmetric reachability. Wireless
interfaces also exhibit time varying performance that can
significantly impact local communication.
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 +-|-+ +-|-+ +-|-+
| R1| | R2| | R3|
+---+ +---+ +---+
R1 R2 R3
-------------------------
Neighbors * R2 R1 R2
* R3
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.
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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
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 nearby nodes. 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 fuzzy neighbor relationships in MANET, 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.
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4.2.3. MANET Membership
Given MANETs' characteristics (mobile, wireless, ad hoc), determining
a MANETs' membership is difficult, if not impossible in certain
scenarios.
/----------------------\ /----------------------\
| MANET | | MANET |
| +----+ +----+ +----+ | | +----+ +----+ +----+ |
| |MAN1+-+MAN2+-+MAN3| | | |MAN1+-+MAN2+-+MAN3| |
| +-+--+ +----+ +----+ | | +----+ +----+ +-+--+ |
| | | | | |
| +-+--+ | Change | +-+--+ |
| |MAN4| | in | |MAN7| |
| +----+ | Time | +----+ |
| \ | \----------------------/
| +----+ |
| |MAN5| |
| +----+ | /----------------------\
| / \ | | MANET |
| +----+ +----+ | | +----+ +----+ +----+ |
| |MAN6| |MAN7| | | |MAN6+-+MAN4+-+MAN5| |
| +----+ +----+ | | +----+ +----+ +----+ |
\----------------------/ \----------------------/
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
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routing information about the MANET topology to other routing
regions.
5. Addressing & the MANET Prefix Model
This section presents an architectural model for MANETs which
preserves the integrity of the IP addressing architecture while
allowing for the particularities of MANETs.
This architectural model considers MANET routers as simply routers
with nodes attached, as illustrated in Figure 5. The attached nodes
may be "external" (i.e. attached to the router via other network
interfaces) or an internal addressable host logic (IAH) - however the
important observation to make is, that the links between these
entities and the router are classic IP links. This fact implies
that, from the point of view of these entities and the applications
running on them, connectivity is via a classic IP link. Therefore
applications are not exposed to the specific characteristics of
interfaces with asymmetric reachability or unknown address
membership. Hosts are connected to the MANET via a MANET router,
which has one or more interfaces participating in MANET routing.
<~~~~~~+~~~~~~> MANET <~~~~~~+~~~~~~>
| Interfaces |
''''''''''|'''''''''' ''''''''''|''''''''''
'MANE +-|-+ ' ' +-|-+ MANET '
'Router | R ................................ R | Router'
' +-+-+ ' ' +-+-+ '
' : : ' ' : : '
' : +---+ ' ' : +---+ '
' : |IAH| ' ============ ' : |IAH| '
' : +---+ ' = : = ' : +---+ '
'''''''''':'''''''''' =Classic IP= '''''''''':''''''''''
+......+......+ =Interfaces= +......+......+
: : ============ : :
+-+-+ +-+-+ +-+-+ +-+-+
| N | * * * | N | | N | * * * | N |
+---+ +---+ +---+ +---+'
Figure 5: MANET Addressing Model
A MANET router can be delegated zero or more prefixes. If a MANET
router is delegated a prefix p::, this prefix can be assigned to its
classic IP link(s), and nodes can be assigned addresses from within
this prefix, and configured with this prefix as illustrated in
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Figure 6. Specifically, interface(s) with asymmetric reachability or
unknown/indeterministic membership attached to the router are *not*
configured with this prefix. The configuration of these interfaces
are detailed below.
MANET <~~~~~~+~~~~~~> Example
Interface | Assigned
''''''''''|'''''''''' Prefix
' MANET +-|-+ ' =========
' Router| R | ' <=== P:: =
' +-+-+ ' =========
' : : '
' : +---+ ' =========
============ ' : |IAH| ' <=== P:1:: =
= : = ' : +---+ ' =========
=Classic IP= '''''''''':''''''''''
=Interfaces= :
============ : =========
+......+......+ <=== P:2:: =
: : =========
+-+-+ +-+-+
| N | * * * | N |
+---+ +---+
P:2::1 P:2::N
Figure 6: MANET Router and Prefixes
MANET specific behaviors are exclusively exposed to the MANET
interface(s) of the routers. This behaviors may include asymmetric
neighborhoods, semi-broadcast interfaces, fuzzy neighbor
relationships, unknown/indeterministic membership, rapid topology
dynamics, etc.
The following characteristics deserve particular mention, since they
distinguish these MANET interface(s) and the MANET link model from
the classic IP link model:
Unique Prefixes
These MANET interfaces must be configured with unique prefixes.
The reason for this requirements is so that no two MANET
interfaces are configured to appear within the same IP prefix,
since node membership cannot be ensured. Some common ways to
achieve this are:
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* unnumbered interfaces (IPv4) [RFC1812];
* link-local addresses (IPv6);
* /128 (IPv6) or /32 (IPv4) prefixes.
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. Note that the
above statement is not an exception, but simply a clarification
that MANET are no different from other networks in this respect.
Link-local Multicast/Broadcast Scope
On a MANET interface, a packet sent to a link-local multicast or
broadcast addresses reaches the interfaces of neighboring nodes,
regardless of their configured addresses. Link-local packets are
never forwarded and since a MANET may span several hops, nodes
cannot assume that a packet sent to a link-local address will
reach all MANET routers 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 MANET aware router, assumed
to be MANET aware, and running appropriate protocols;
o MANET interfaces, forming a multihop MANET area, may use a site
prefix;
o nodes and subnets on non-MANET interface(s) assume a classic IP
link model;
o applications on hosts and protocols assuming classic IP interfaces
run unmodified.
MANET protocols are protocols which are developed to work on MANET
interfaces and to be MANET-aware. 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 on 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
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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. On the other
hand, this transparency may lead to performance problems. For
example, if the L3 protocols make heavy use of broadcast messaging or
if 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
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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, and neighbor state
changes to reduce the messaging or latency in making decisions.
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 MANs in a MANET is an important consideration.
This number is not the complete number of nodes in a MANET (since
MANs may support an arbitrary number of connected nodes) but a
measure of the number of MAN participating as a cohesive flat routing
area. That is, the number of MAN within a single routing region.
While the number of peer MANs does not define scalability of a MANET
protocol, it is often useful to discuss the number of peer MAN to get
a feel for maturity of typical deployment solutions. For simplicity
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we define the following network sizes to aid in discussion:
Small
2-30 MAN peers
Moderate
30-100 MAN peers
Large
100-1000 MAN peers
Very large
Larger than 1000 MAN 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
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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
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
Alan Cullen
Justin Dean
Christopher Dearlove
Tom Henderson
Bob Hinden
Thomas Narten
Charles Perkins
Subhranshu Singh
Fred Templin
Dave Thaler
Seung Yi
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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]
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-11 (work in progress), March 2007.
[I-D.ietf-manet-smf]
Macker, J., "Simplified Multicast Forwarding for MANET",
draft-ietf-manet-smf-04 (work in progress), March 2007.
[I-D.templin-autoconf-dhcp]
Templin, F., "MANET Autoconfiguration",
draft-templin-autoconf-dhcp-07 (work in progress),
March 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
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(IPv6) Addressing Architecture", RFC 3513, April 2003.
[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.
Authors' Addresses
Ian D Chakeres
Motorola
Bagmane Tech Park
66/1, Plot 5, CV Raman Nagar
Bangalore, Karnataka 560093
India
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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