Routing in MANETS

8/7/2019 Routing in MANETS

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TABLE OF CONTENTS

I. INTRODUCTION ..................................................................................................2

II. EVOLUTION..........................................................................................................5

III. WHAT IS ROUTING? ...........................................................................................7

IV. ROUTING PROTOCOLS ....................................................................................10V. TYPES OF PROTOCOLS.....................................................................................11

VI. Table-Driven/Proactive Protocols......................................................................... 11

VII. On-Demand-Driven/Reactive Protocol................................................................. 14VIII. Hybrid Protocol..................................................................................................... 19

IX. COMPARISON OF PROTOCOLS.......................................................................22

X. APPLICATIONS OF MANETS...........................................................................23XI. CONCLUSION......................................................................................................25

XII. REFERENCES......................................................................................................27


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SRSIT Routing in MANETS

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INTRODUCTION

As the importance of computers in our daily life increases it also sets new

demands for connectivity. Wired solutions have been around for a long time but there is

increasing demand on working wireless solutions for connecting to the Internet, reading

and sending E-mail messages, changing information in a meeting and so on.

Wireless communication is the transfer of information over a

distance without the use of electrical conductors or "wires". The

distances involved may be short (a few meters as in television remote

control) or long (thousands or millions of kilometers for radio

communications). When the context is clear, the term is often

shortened to "wireless". Wireless communication is generally

considered to be a branch of telecommunications

It encompasses various types of fixed, mobile, and portable two

way radios, cellular telephones, personal digital assistants (PDAs), and

wireless networking. Other examples of wireless technology include

GPS units, garage door openers and or garage doors, wireless

computer mice, keyboards and headsets, satellite television and

cordless telephones.

There are solutions to these needs, one being wireless local area

network that is based on IEEE 802.11 standard. However, there is

increasing need for connectivity in situations where there is no base

station (i.e. backbone connection) available (for example two or more

PDAs need to be connected). This is where ad hoc networks step in.

An ad-hoc (or "spontaneous") network is a local area network or

other small network, especially one with wireless or temporary plug-in

connections, in which some of the network devices are part of the

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network only for the duration of a communications session or, in the

case of mobile or portable devices, while in some close proximity to

the rest of the network.

Ad-hoc networks are an emerging area of mobile computing. There are various

challenges that are faced in the Ad-hoc environment. These are mostly due to the

resource poorness of these networks. They are usually set up in situations of emergency,

for temporary operations or simply if there are no resources to set up elaborate networks.

Ad-hoc networks therefore throw up new requirements and problems in all areas of

networking.

In Latin, ad hoc literally means "for this," further meaning "for this

purpose only," and thus usually temporary. The term has been applied

to future office or home networks in which new devices can be quickly

added, and thus creates a reliable infrastructured wireless network.

In the recent years communication technology and services have

advanced. Mobility has become very important, as people want to

communicate anytime from and to anywhere, in the areas where there

is little or no infrastructure is available or the existing wireless

infrastructure is expensive and inconvenient to use.

It is a good and emblematic description of the idea why ad hoc

networks are needed. They can be set up anywhere without any need

for external infrastructure (like wires or base stations). They are often

mobile and thats why a term MANET is often used when talking aboutMobile Ad hoc NETworks.

Mobile Ad hoc Networks, called MANETs, are becoming useful. They are

going to become integral part of next generation mobile services. A

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MANET is a collection of wireless nodes that can dynamically form a

network to exchange information without using any pre-existing fixed

network infrastructure.

The term MANET (Mobile Adhoc Network)refers to a multihop packet

based wireless network composed of a set of mobile nodes that can

communicate and move at the same time , without using any kind of

fixed wired infrastructure.

MANET is actually self organizing and adaptive networks that can be

formed and deformed on-the-fly without the need of any centralized

administration. The special features of MANET bring this technology

great opportunity together with severe challenges.

MANETs are also defined as follows: A "mobile ad hoc network"

(MANET) is an autonomous system of mobile routers (and associated

hosts) connected by wireless links the union of which forms an

arbitrary graph. The routers are free to move randomly and organize

themselves arbitrarily; thus, the network's wireless topology may

change rapidly and unpredictably. Such a network may operate in a

standalone fashion, or may be connected to the larger Internet.

The strength of the connection can change rapidly in time or even

disappear completely. Nodes can appear, disappear and re-appear as

the time goes on and all the time the network connections should work

between the nodes that are part of it. As one can easily imagine, thesituation in ad hoc networks with respect to ensuring connectivity and

robustness is much more demanding than in the wired case.

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Ad hoc networks are networks are not (necessarily) connected to any

static (i.e. wired) infrastructure. An ad-hoc network is a LAN or other

small network, especially one with wireless connections, in which some

of the network devices are part of the network only for the duration ofa communications session or, in the case of mobile or portable devices,

while in some close proximity to the rest of the network.

In ad hoc networks all the communication network protocols should be distributed

throughout the communication terminals (i.e. the communication terminals should be

independent and highly cooperative

EVOLUTION

A computer network is a system for communication between

computers. These network may be fixed (cabled, permanent) or

temporary (as via modems or null modems). Carrying instructions

between calculation machines and early computers was done by

human users.

In September, 1940 George Stibitz used a teletype machine to send

instructions for a problem set from his Model K at Dartmouth College in

New Hampshire to his Complex Number Calculator in New York and

received results back by the same means. Linking output systems like

teletypes to computers was an interest at the Advanced Research

Projects Agency ARPA when, in 1962,J.C.R. Licklider was hired and

developed a working group he called the 'Intergalactic Network',a

precursor to the ARPANet.

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In 1964 researchers at Dartmouth developed a time sharing system for

distributed users of large computer systems. The same year, at MIT, a

research group supported by General Electric and Bell Labs used a

computer (DEC's PDP-8) to route and manage telephone connections.In 1968 Paul Baran proposed a network system consisting of

datagrams or packets that could be used in a packet switching network

between computer

systems.

In 1969 the University of California at Los Angeles, SRI (in Stanford),

University of

California at Santa Barbara, and the University of Utah were connected

as the beginning of the ARPANet network using 50 kbit/s circuits.

Networks and the technologies needed to connect and communicate

through and between them, continue to drive computer hardware,

software, and peripherals industries. This expansion is mirrored by

growth in the numbers and types of users of networks from

researchers and businesses to families and individuals in everyday use.

The types of wireless technologies are as follows. The first-

generation (1G) denotes analogue networks such as Nordic Mobile

Telephone (NMT) and second-generation (2G) denotes the first digital

solutions, such as Global System for Mobile Communications (GSM).

Recently introduced General Packet Radio Service (GRPS) and related

GSM

extensions have been referred to as 2.5G and finally the Universal

Mobile Telecommunication System (UMTS) and International Mobile

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Telecommunication System 2000 (IMT-2000) [1] efforts as the third-

generation (3G).

At present, 3G mobile communication systems are just beginning to bedeployed, while research on the next generation of mobile

communications, the fourth-generation (4G) wireless networks, begins

to pave the way for the future.

The boundary between mobile personal telecommunications and

wireless computer networks is disappearing, through the convergence

of mobile and wireless communications with Internet services. With the

rapid improvement in both wireless networks and mobile terminals,

great increases have emerged in all the fields of mobile

communications,

including the number of mobile subscribers, the deployment of mobile

communication systems, and the new advances in mobile techniques.

The next generation of wireless communications will be based on a

global system of both wired fixed and wireless mobile networks and

services.

WHAT IS ROUTING?

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"Routing," which refers to the procedure of discovering,

selecting, and employing paths from one place to another (or too many

others) in a network.

Routing is the process of selecting paths in a network along which to

send network traffic. Routing is performed for many kinds of networks,

including the telephone network, electronic data networks (such as the

Internet), and transportation networks. This article is concerned

primarily with routing in electronic data networks using packet

switching technology.

Routing, in a more narrow sense of the term, is often contrasted with

bridging in its assumption that network addresses are structured and

that similar addresses imply proximity within the network. Because

structured addresses allow a single routing table entry to represent the

route to a group of devices, structured addressing (routing, in the

narrow sense) outperforms unstructured addressing (bridging) in large

networks, and has become the dominant form of addressing on the

Internet, though bridging is still widely used within localized

environments.

Since the topology of the network is constantly changing, the issue of

routing packets between any pair of nodes becomes a challenging

task. Most protocols should be based on reactive routing instead of

proactive. Multicast routing is another challenge because the multicast

tree is no longer static due to the random movement of nodes withinthe network. Routes between nodes may potentially contain multiple

hops, which is more complex than the single hop communication.

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The fact that it may be necessary to hop several hops before a

packet reaches the destination, a routing protocol is needed. The

routing protocol has two main functions, selection of routes for various

source-destination pairs and the delivery of messages to their currentdestination. The second function is conceptually is straight forward

using a variety of protocols and data structures. This report is focused

on selecting and finding routes.

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ROUTING PROTOCOLS

A routing protocol is a protocol that specifies how routers

communicate with each other, disseminating information that enables

them to select routes between any two nodes on a computer network,

the choice of the route being done by routing algorithms.

Each router has a priori knowledge only of networks attached to it

directly. A routing protocol shares this information first among

immediate neighbors, and then throughout the network. This way,

routers gain knowledge of the topology of the network.

The term routing protocol may refer specifically to one operating at

layer three of the OSI model, which similarly disseminates topology

information between routers. Many routing protocols used in the public

Internet are defined in documents called RFCs.

A protocol is derived from the Greek word protocollon, which was a leaf of paper glued

to a manuscript volume, describing its contents. It is the special set of rules that end

points in a telecommunication connection use when they communicate.

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TYPES OF PROTOCOLS

Table-Driven/Proactive Protocol.

On-Demand-Driven/Reactive Protocol.

Hybrid Protocol.

Table-Driven/Proactive Protocols

This protocol maintains fresh lists of destinations and their routes by periodically

checking routing tables throughout the network.Periodically exchange the routing tables;

maintain consistent, up-to-date routing information from each node to every

other node in the network.

Advantage: Produces the required route immediately.

Disadvantage: Waste too much bandwidth in a network with frequently

changing topology.

Some of the protocols:

DSDV (Destination-Sequenced Distance-Vector)

Destination-Sequenced Distance-Vector Routing (DSDV) is a table-driven

routing scheme for ad hoc mobile networks based on the Bellman-Ford algorithm. It was

developed by C. Perkins and P.Bhagwat in 1994. The main contribution of the algorithm

was to solve the Routing Loop problem. Each entry in the routing table contains a

sequence number, the sequence numbers are generally even if a link is present; else, an

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odd number is used. The number is generated by the destination, and the emitter needs to

send out the next update with this number. Routing information is distributed between

nodes by sending full dumps infrequently and smaller incremental updates more

frequently.

Advantages of DSDV: DSDV was one of the early algorithms available. It is quite

suitable for creating ad hoc networks with small number of nodes. Since no formal

specification of this algorithm is present there is no commercial implementation of this

algorithm. Many improved forms of this algorithm have been suggested.

Disadvantages of DSDV: DSDV requires a regular update of its routing

tables, which uses up battery power and a small amount of bandwidth even whenthe network is idle. Whenever the topology of the network changes, a new sequence

number is necessary before the network re-converges; thus, DSDV is not suitable for

highly dynamic networks.

WRP (Wireless Routing Protocol)

Wireless Routing Protocol (WRP) is a proactive unicast routing protocol for

mobile ad-hoc networks (MANETs). WRP uses an enhanced version of the distance-vector routing protocol, which uses the Bellman-Ford algorithm to calculate paths.

Because of the mobile nature of the nodes within the MANET, the protocol introduces

mechanisms which reduce route loops and ensure reliable message exchange.

The wireless routing protocol (WRP), similar to DSDV, inherits the properties of the

distributed Bellman-Ford algorithm. To counter the count-to-infinity problem and to

enable faster convergence, it employs a unique method of maintaining information

regarding the shortest distance to every destination node in the network and the

penultimate hop node on the path to every destination node.

Advantages of WRP: Since WRP, like DSDV, maintains an up-to-date view of the

network, every node has a readily available route to every destination node in the

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network. It differs from DSDV in table maintenance and in the update procedures. While

DSDV maintains only one topology table, WRP uses a set of tables to maintain more

accurate information.

Disadvantages of WRP: At high mobility, the control overhead involved in updating

table entries is almost the same as that of DSDV and hence is not suitable for highly

dynamic and also for a very large ad hoc wireless network.WRP requires large memory

storage and resources in maintaining its tables. The protocol is not suitable for large

mobile ad hoc networks as it suffers from limited scalability.

CGSR (Clusterhead Gateway Switch Routing)

Mobile nodes are partitioned into clusters and a clusterhead is elected using adistributed algorithm. All nodes in the communication range of the clusterhead belong to

its cluster. A node that is in the communication range of two or more clusterheads is

called a gateway node.CGSR uses a Least Cluster Change (LCC) clustering algorithm. A

clusterhead change occurs only when two clusterheads come into one cluster or one of

the nodes moves out of the range of all the clusterheads.

A clusterhead is able to control a group of ad-hoc hosts, this means that it is in charge of

broadcasting within the cluster, forwarding messages and dynamic channel scheduling.

Each node maintains 2 tables:

a cluster member table, containing the cluster head for each destination node

a DV-routing table, containing the next hop to the destination.

The cluster member table is broadcasted periodically. A node will update the entries in its

cluster member table on receiving a new one from its neighbors. Sequence numbers are

used as in DSDV.

STAR (Source Tree Adaptive Routing)

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The Source Tree Adaptive Routing protocol was the first proactive routing

protocol that works with link-state information and was faster then on-demand protocols.

It was also the first proactive routing protocol where LORA principle was implemented.

STAR doesnt take shortest paths for keeping control messages low. STAR identifiesevery node with a fix address. Big advantage is that no periodically updates are needed.

After the start procedure a source tree contains links to every neighbor. Next step, means

first update step, STAR sends his own source tree immediately as update to all other

neighbors. So every router can built with his own source tree and the received ones, a

topology graph containing the whole network. Those updates consist of one or more LSU

(Link-State Update Unit).

On-Demand-Driven/Reactive Protocol

These protocols find a route on demand by flooding the network with Route

Request packets.Be lazy create routes only when desired by the source node.

Advantage: Less control traffic.

Disadvantage: Delay with route discovery

Some of the protocols are:

DSR (Dynamic Source Routing)

The Dynamic Source Routingprotocol (DSR) is a simple and efficient routing

protocol designed specifically for use in multi-hop wireless ad hoc networks of mobile

nodes. DSR allows the network to be completely self-organizing and self-configuring,

without the need for any existing network infrastructure or administration. The protocol

is composed of the two mechanisms ofRoute Discovery and Route Maintenance, which

work together to allow nodes to discover and maintain source routes to arbitrary

destinations in the ad hoc network.

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The Dynamic Source Routing protocol (DSR) [Johnson 1994, Johnson

1996a, and Broch 1999a] is a simple and efficient routing protocol

designed specifically for use in multi-hop wireless ad hoc networks of

mobile nodes. Using DSR, the network is completely self-organizingand self-configuring, requiring no existing network infrastructure or

administration. Network nodes (computers) cooperate to forward

packets for each

other to allow communication over multiple hops between nodes not

directly within wireless transmission range of one another.

Advantages of DSR:Reactive routing protocols have no need to periodically flood the

network for updating the routing tables like table-driven routing protocols do.

Intermediate nodes are able to utilize the Route Cache information efficiently to reduce

the control overhead. The initiator only tries to find a route (path) if actually no route is

known (in cache). Current and bandwidth saving because there are no hello messages

needed (beacon-less).

Disadvantages of DSR: The Route Maintenance protocol does not

locally repair a broken link. The broken link is only communicated to

the initiator. The DSR protocol is only efficient in MANETs with less

then 200 nodes. Problems appear by fast moving of more hosts, so

that the nodes can only move around in this case with a moderate

speed. Flooding the network can cause collusions between the packets.

Also there is always a small time delay at the begin of a new

connection because the initiator must first find the route to the target.:

AODV (Ad hoc On-Demand Distance Vector Routing)

Ad hoc On-Demand Distance Vector (AODV) Routing is a routing protocol for

mobile ad hoc networks (MANETs) and other wireless ad-hoc networks. It is jointly

developed in Nokia Research Center of University of California, Santa Barbara and

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University of Cincinnati by C. Perkins and S. Das .AODV is capable of both unicast and

multicast routing. It is a reactive routing protocol, meaning that it establishes a route to a

destination only on demand. In contrast, the most common routing protocols of the

Internet are proactive, meaning they find routing paths independently of the usage of thepaths. AODV is, as the name indicates, a distance-vector routing protocol. AODV avoids

the counting-to-infinity problem of other distance-vector protocols by using sequence

numbers on route updates, a technique pioneered by DSDV.

Advantages of AODV: the main advantage of this protocol is that routes are established

on demand and destination sequence numbers are used to find the latest route to the

destination. The connection setup delay is lower.

Disadvantages of AODV: One of the disadvantages of this protocol is that intermediate

nodes can lead to inconsistent routes if the source sequence number is very old and the

intermediate nodes have a higher but not the latest destination sequence number, thereby

having stale entries. Also multiple RouteReply packets in response to a single

RouteRequest packet can lead to heavy control overhead. Another disadvantage of

AODV is that the periodic beaconing leads to unnecessary bandwidth consumption.

TORA (Temporally-Ordered Routing Algorithm)

The TORA attempts to achieve a high degree of scalability using a "flat", non-

hierarchical routing algorithm. In its operation the algorithm attempts to suppress, to the

greatest extent possible, the generation of far-reaching control message propagation. In

order to achieve this, the TORA does not use a shortest path solution, an approach which

is unusual for routing algorithms of this type.

TORA builds and maintains a Directed Acyclic Graph rooted at a destination. No three

nodes may have the same height.

Information may flow from nodes with higher heights to nodes with lower heights.

Information can therefore be thought of as a fluid that may only flow downhill. By

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maintaining a set of totally-ordered heights at all times, TORA achieves loop-free

multipath routing, as information cannot 'flow uphill' and so cross back on itself.

the key design concepts of TORA is localization of control messages to a very small set

of nodes near the occurrence of a topological change.To accomplish this,nodes need to

maintain the routing information about adjacent (one hop) nodes.

Advantages of TORA:That of an on-demand routing protocol create a

DAG only when necessary.

Multiple paths created. Good in dense network.

Disadvantages of TORA: Same as on-demand routing protocols.

Not much used since DSR and AODV outperform TORA.

ABR (Associative Based Routing)

ABR protocol focuses on route longevity i.e. link stability and has fewer route

reconstructions which reduces routing overhead. Associativity ticks are used to signal the

stability of the mobile hosts via the usage of beacons. Associativity is related to the

spatial, temporal and connection stability of a mobile host. Specifically, associativity is

measured by a nodes connectivity to its other surrounding nodes. In ABR, a mobile host

is said to be in high state of mobility when it has low associativity ticks with its

neighbouring nodes. However, if the associativity tick is high, the mobile host is regarded

to be in a stable state and this is the ideal point at which to select it to perform the routing

procedure. ABR consists of 3 main phases, namely route discovery phase, route

reconstruction phase and route deletion.

Having mentioned the strengths of ABR which differentiates it with the other MANET

on demand routing protocol, it has also other aspects in which need to be improvised.

This paper discusses issues related to ABR and other work done to enhance and

improvise the base protocol, i.e. the ABR protocol. Among others are the aspect of

multicasting, improvisation on the route reconstruction method, the operation

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complexity and also the communication complexity. Operation complexity (OC) can be

defined as the number of steps required in performing a protocols operation while

communication complexity (CC) can be defined as the number of messages exchanged in

performing a protocols operation. The values discussed in this paper would be in theworst-case analysis.

CBRP (Cluster Based Routing Protocol)

Identifier-based clustering is a better choice than connectivity-

based clustering, according to node movement. When using identifier-

based clustering a node elects itself as the clusterhead if it has the

lowest/highest ID in its neighbourhood, or a neighbour node if one has

a lower ID. Connectivity-based clustering elects the node, which has

the most neighbour nodes, as the clusterhead. So, whenever a

clusterhead looses a neighbour node its connectivity decreases and it

is most likely that another node has to be elected to act as

clusterhead. While in the identifier-based approach, a new clusterhead

has to be chosen only when nodes with lower/heigher ID. The CBRP

uses a variation of the lowest-ID algorithm, in which an identifier-based

algorithm. In order to support the cluster formation process each node

uses a neighbour table, where it stores information about its neighbour

nodes, such as their IDs, their role in the cluster (clusterhead or

member node) and the status of the link to that node (uni-/bi-

directional). The neighbour table is maintained by periodically

broadcasting HELLO messages. A HELLO message contains information

about one nodes state, its neighbour table and its cluster adjacency

table.

The following states describe the clustering process depending on the

current node state. These states are:

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________________________________________________________________________UNDECIDED:This means the node does not belong to any cluster: this

usually occurs if a new node appears in the network. Thus, if it receives

a HELLO message from a clusterhead and there is a bi-directional link

between them it changes its state to be member of the clusterindicated by the clusterhead. Otherwise it looks up in its neighbour

table if it has any bi-directional links. If so, it becomes itself the

clusterhead of a new cluster, if not, it remains in the undecided state

and tries again.

CLUSTER HEAD:If a clusterhead detects that it has a bi-directional link

to another clusterhead for a time period, it changes its state to

member if the other clusterhead has a lower ID. Otherwise it stays the

clusterhead and the other node has to change its state. This is a

special case which may result in cluster re-organisation.

MEMBER: If a member looses its clusterhead, it looks for bi-directional links to other

nodes. If it detects any, it changes its state to clusterhead if it has the lowest ID, otherwise

it switches to the undecided state. Each member node belongs at least to one cluster

Hybrid Protocol

Its a combination of both pro-active and reactive protocols. Incorporates some aspects

of the proactive and some aspects of the reactive protocols.

Some of the protocols are:

ZRP (Zone Routing Protocol)

Reduces the control overhead.

Decreases the latency.

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COMPARISON OF PROTOCOLS

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Parameters Table Driven/Proactive On demand

Driven/Reactive

Hybrid

Loop- freeYes Yes Yes

Multiple routes No No Yes

Distributed Yes Yes Yes

Reactive No Yes Partially

Unidirectional link support No No No

QoS Support No No No

Multicast No Yes No

Power Conservation No No No

Periodic broadcast Yes Yes Yes


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APPLICATIONS OF MANETS

Some of the applications of MANETs are:

1) Military battlefield:

Military equipment now routinely contains some

sort of computer equipment. Ad hoc networking would allow the

military to take advantage of commonplace network technology to

maintain an information network between the soldiers, vehicles, and

military information head quarters. The basic techniques of ad hoc

network came from this field.

2) Commercial sector:

Ad hoc can be used in emergency/rescue operations for

disaster relief efforts, e.g. in fire, flood, or earthquake. Emergency

rescue operations must take place where non-existing or damaged

communications infrastructure and rapid deployment of a

communication network is needed. Information is relayed from one

rescue team member to another over a small handheld. Other

commercial scenarios include e.g. ship-to-ship ad hoc mobile

communication, law enforcement, etc.

3) Local level:

Ad hoc networks can autonomously link an instant and

temporary multimedia network using notebook computers or palmtop

computers to spread and share information among participants at a

e.g. conference or classroom. Another appropriate local level

application might be in home networks where devices can

communicate directly to exchange information. Similarly in other

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civilian environments like taxicab, sports stadium, boat and small

aircraft, mobile ad hoc communications will have many applications.

4) Personal Area Network (PAN):

Short-range MANET can simplify the

intercommunication between various mobile devices (such as a PDA, a

laptop, and a cellular phone). Tedious wired cables are replaced with

wireless connections. Such an ad hoc network can also extend the

access to the Internet or other networks by mechanisms e.g. Wireless

LAN (WLAN), GPRS, and UMTS.

5) Inter-vehicle communications:

It is one area where the ad hoc networks

could really change the way we communicate covering personal

vehicles as well as professional mobile communication needs. Also, it is

area where no conventional (i.e. wired) solutions would do because of

the high level of mobility. When considering demanding surroundings,

say mines for example, then neither would the base station approach

work but we must be able to accomplish routing via nodes that are

part of the network i.e. we have to use ad hoc network.

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CONCLUSION

We discussed ad-hoc and mobile adhoc networks, routing in

MANETs, MANET protocols and comparison of MANET protocols. The

salient features of adhoc networks pose both challenges and

opportunities.

Ad hoc networks can be implemented using various techniques like

Bluetooth or WLAN for example. The definition itself does not imply any

restrictions to the implementing devices.

Ad Hoc networks need very specialized security methods. There is no

approach fitting all networks, because the nodes can be any devices.

The computer security in the nodes depends on the type of node, and

no assumptions on security can be made.

But with the current MAC layer and routing solutions the true and

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working ad hoc network is just a dream for now. However, it can be

used with relatively small networks and potentially some very nice

applications can be realized.

Although some peer-to-peer type of solutions work nicely already

today, it would be nice to see that some new and innovative solutions

would be seen in the arena of ad hoc networks since it is not hard for

one to imagine a countless number of nice ad hoc based applications

that would make the world at least a bit better place.

Mobile ad hoc networking is one of the most important and essential

technologies that support future pervasive computing scenario. The

special characters of MANET bring this technology great opportunity

together with severe challenges.

Currently MANET is becoming more and more interesting research

topic and there are many research projects employed by academic and

companies all over the world. Various interesting issues are

investigated that cover all aspects of ad hoc wireless networks.

Meanwhile, many routing protocols designed for ad hoc networks have

been proposed as Internet Draft and RFC of IETF. MANETs can be

exploited in a wide area of applications, from military, emergency

rescue, law enforcement, commercial,

to local and personal contexts.

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REFERENCES

[1] Jean-Pierre Hubaux, Levente Buttyn, and Srdan Capkun. The

Quest for Security in Mobile Ad Hoc Networks.

[2] In Proceedings of the ACM Symposium on Mobile Ad Hoc

Networking And Computing (MobiHOC 2001), Long Beach, CA, USA,

2001.

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[3] Sonja Buchegger and Jean-Yves Le Boudec. Performance Analysis

of the CONFIDANT Protocol (Cooperation of Nodes: Fairness in Dynamic

Ad-hoc Networks).

[4] In The Third ACM International Symposium on Mobile Ad HocNetworking and Computing (MobiHoc), Lausanne, Switzerland, June

2002.

[5] M. Nidd, Service Discovery in DEAPspace, IEEE Personal

Communications, August 2001.

[6] ftp://ftp.netlab.ohio-state.edu/pub/jain/courses/cis788-

99/adhoc_routing/index.html, June 2001.

[7] P. Varaiya, Smart Cars on Smart Roads: Problem of Control, IEEE

Trans. Auto. Control, vol. 38,no. 2, 1993

[8] Thomas Clausen, Philippe Jacquet, Anis Laouiti, et al.,

Optimized Link State Routing Protocol,draft-ieft-manet-olsr-06.txt,

September 2002 (expired).

[9] Amir Qayyum, Laurent Viennot, and Anis Laouiti, Multipoint

relaying: An efficient technique for flooding in mobile wireless

networks, March 2000

[10] Mario Gerla, Xiaoyan Hong, and Guangyu Pei, Fisheye State

Routing Protocol (FSR) for Ad Hod Networks, draft-ietf-manet-fsr-

03.txt, June 2002 (work in progress).

[11] Richard G. Ogier, Fred L. Templin, Bhargav Bellur, and Mark

G. Lewis, Topology Broadcast Based on Reverse-Path Forwarding

(TBRPF), draft-ietf- manet-tbrpf-05.txt, March 2002 (expired).

[12] David B. Johnson, Routing in Ad Hoc Networks of Mobile

Hosts, Proceedings of the IEEE workshop on Mobile ComputingSystems and Applications, December 1994.

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Routing in MANETS

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