1. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
Review of Multipath Routing Protocol with
Load Balancing in MANET
Prof.S.A.Jain1
, Pratik Waghmare2
, Swapnil Sonawane3
Department of Computer Engineering, University of Pune
MIT Academy of Engineering, Alandi (D), Pune, India
1
sajain@comp.maepune.ac.in 2
pratikwaghmare92@gmail.com 3
sonawane.swapnil91@gmail.com
Abstract: Mobile Ad-hoc Network (MANET) is a self maintaining,
self configuring and self organizing Network. There is no fixed
infrastructure and also there is no base station for MANET.
When nodes change there position then topology changes
therefore it is difficult to design the protocol for the MANET.
Routing is an important factor in mobile ad hoc network which
not only works well with a small network, but also it can also
work well if network get expanded dynamically. Mobile nodes in
the MANET have limited transmission capability they
intercommunicate by multi hope relay. Multipath routing has
many challenges such as limited wireless bandwidth, low device
power, dynamically changing network topology. To answer those
challenges many multipath Routing Protocol have been proposed.
Keywords: Disjoint Multipath, Multi hop, reliability, Congestion
Control.
I.INTRODUCTION
Mobile ad hoc networks (MANET) are Infrastructure less
networks. MANET is self maintaining, self configuring and
self organizing network. Each mobile node has limited
resources such as limited battery power, limited bandwidth and
limited processing power. In MANET mobile node
communicate as a multi-hop fashion. So due to limited
processing power load increases on node in turn congestion
occur. Therefore nodes discard some packets due to overload.
This existing paper introduce the new protocol called Load
Balancing Multipath Routing Protocol based on AODV
protocol (Ad-hoc On Demand protocol).In LB-M routing
protocol we proposed that load is equally distribute to all other
nodes which we discover during multipath rout discovery
process.LB-M avoids the network from gating congested every
time when load increases on nodes.
II. RELATED WORK
A. AODV (Ad-hoc On demand Distance Vector
Protocol) :
The AODV is the Reactive on demand routing protocol
means nodes which is not in the active path does not
need to maintain the routing information. Here on
demand means if source want to send packet then
source initialised route discovery on demand. Like
DSR, AODV also contain two mechanisms of Route
Discovery and Route Maintenance. But Route Request
(RREQ) structure of AODV is different than the DSR
protocol. To detect a fresh or new route from an old
route, each node maintains two counters such as node
sequence ID and broadcast ID. Each route request
(RREQ) packet contains information about the
destination sequence number which is used for
distinguish from remaining node and the source
sequence number in addition to source address and
destination address. The sequence numbers are used to
indicate the freshness and newness of a route in
network.
1) Route Discovery:
Fig 1 RREQ and RREP Propagation
Route Discovery is the mechanism in which source
discovers the route to destination. If source want to send the
packet to destination then source Discovers the route to
destination in its Route cache. If source cannot find the route
then source generates the RREQ (Route Request) packet and
send it to its neighbour. When a neighbour of a source receives
a request packet, it first checks whether the request packet is
intended for it or not. If a neighbour discovers that it is the
destination, it sends a reply back to the source after copying
the routing information contained in the route request packet
into a route reply packet. If it is not the destination, it checks if
there is any route available in the route cache for that

2. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
destination. If this neighbouring node is neither a destination
nor does it have a route in the route cache to that destination, it
appends its address in the route request packet, and then it re-
broadcasts a route request packet to its neighbours. This
process continuous till source packet reaches the destination.
When destination receives the Route Request packet from
source then destination generates the RREP (Route Reply
packet) packet and send to the source. After receiving the
RREP packet source sends the data packet along the route
which is contain in the RREP.
2) Route Maintenance:
To avoid the congestion in the network and also prevent the
link breakage from occurring AODV uses the Route
maintenance mechanism by generating the REEP message.
3) Advantages:
1) Less time for connection setup
2) On demand route establishment
3) Provide uncasing or multicasting or broadcasting
4) Limitations:
1) Packet delivery ratio increases as network increase.
2) Long delay in route correction.
B. AOMDV (Ad-hoc on Demand Multipath Distance Vector
Protocol)
AOMDV is based on distance vector concept and
uses hop-by-hop routing approach. As AODV, AOMDV also
finds routes on demand by rote discovery mechanism. The
main difference lies in the number of routes found in a route
discovery. The main idea in AOMDV is to compute multiple
paths during route discovery. In AOMDV, RREQs from
different neighbours of the source are accepted at intermediate
nodes.
1) Route Discovery:When source want to send the
packet to destination then it searches the path in its
routing table for the destination. If source does not
get path then broadcast the RREQ packet to
searches the multiple path to destination. After
receiving the RREQ at destination then destination
replays all RREQ packets to find multiple disjoint
paths.
Fig. 2 AOMDV routing protocol
2) Route maintenance:
To avoid from congestion AOMDV uses the route
maintenance mechanism same as the AODV. When
link breakage occur then node at which link
breakage occur than that node sends the RERR
packet to source.
3) Advantages:
1) Allows intermediate nodes to reply RREQ
while still selecting the disjoint paths
2) Multiple routes are established in single
route discovery process.
3) Multiple link-disjoint routes are created.
4) Limitations:
1) AOMDV only consider the hope count to
determine the best path among all the paths.
AOMDV does not consider the path stability.
2) Massage overhead during the route
discovery process.
C. LB-M AODV (Load balancing Multipath Ad-hoc on demand
Distance Vector Protocol):
LB-M AODV is a Load Balancing Multipath AODV
routing protocol which is based on mechanism of AODV. It
uses the multipath instead of single path to increase the packet
delivery ratio & achieves the load balancing by equally
distributing the packets along this multipath.
1) Route Discovery:

3. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
Fig. 3 LB-M AODV Routing protocol
LB-M AODV follows the same mechanism of Route
discovery of AODV, AOMDV where source initiates the
Route discovery process by generating the RREQ packet &
pass it its entire neighbor for achieving the path to destination.
2) Route maintenance:
LB- M AODV also follows the route maintenance
mechanism of AODV. Route maintenance mechanism is used
for to avoid the congestion from Occurring. If there is any
congestion occur or link breakage then LBM AODV chooses
the backup path for forwarding.(Here protocol uses one
primary path & all other paths are stored in the database so
when primary path gets fail then instead of new route
discovery process source choose alternative path from the
database
3) Advantages:
1) The main advantage of our protocol is we use the
multipath instead of single path which definitely
increases the path delivery path ratio.
2) On demand routing.
D. BACK UP PATH ROUTING PROTOCOL:
Ad-hoc mobile networks are very dynamic, self
organizing, self maintaining networks which has not
particular infrastructure & base station like cellular
networks. Every node acts as a router for forwarding
the data packets. Back up Path Routing Protocol is
used to store backup routes from multiple routes
available between source and destination, in order to
provide the next possible route immediately when the
link fails during the data transmission.
1) Working model:
The working model of this protocol is to select a
primary path as well as a set of alternate paths (i.e.,
secondary paths). Unlike the DSR protocol, a
destination node only replies to two requests instead
of all requests. One reply contains a primary path and
the other reply contains a back up path.
Fig. 4 Backup Path Routing
A destination node uses the following three main
criteria to choose a path:
(1) The shortest path.
(2) The shortest delay path.
(3) The maximally disjoint path.
The shortest path is similar to that of the DSR
protocol. The shortest delay path is the path along
which a destination receives a request packet first.
The maximally disjointed-path is the secondary path
rather than the primary path. These three criteria are
combined together for various schemes while
selecting a primary path and a back up path.
E. PRIORITIZE ROUTING PROTOCOL
Prioritize routing protocol is another type of delay aware
routing protocol in which packet delay between source and
destination is minimize. In PRIMAR multiple paths discovers
between sources to destination. The basic aim of this protocol
is to reduce the packet delay by considering priority of each

4. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
packet while sending. In PRIMAR, priority is given to each
packet according to their importance.
1) Working model:
Fig 5 Routing Table of PRIMAR
The routing table showed above uses three fields i.e.
priority, next hope, delay. A node which receives the packet,
according to priority of packet, node sends it to next hope
mention in the routing table
The source node uses an indicator to classify packets
according to their importance therefore routing decisions are
made on this priority of packets. A low priority packet travels
a longer path compared to a higher priority packet. The
priorities are assigned from 1 to M, where M is the indication
of the highest priority. A packet with the highest priority is
sent using the optimal path.
2) Route Discovery:
The route discovery process of PRIMAR is same as that
of AOMDV protocol in which multiple routes are discovers
from source to destination
3) Route Maintenance:
The route Maintenance of PRIMAR is similar to that of
the DSR protocol, but PRIMARs route maintenance is
initiated if a route fails or a route does not meet the delay
requirement of a packet. This change in route maintenance
scheme allows PRIMAR to meet the delay requirements of
high priority traffic.
F.BIASED GEOGRAPHICAL ROUTING
PROTOCOL:
Biased Geographical Routing Protocol (BGR) is
another type of delay aware routing protocol.BGR
increases the delay aware performance of the network.
For this it considers the congestion information in the
network.
1) Working model:
The BGR protocol uses two congestion control
mechanisms, namely
(1) In-network packet splitter (IPS)
(2) End-to-end packet scatters (EPS).
Fig 6 Biased Geographical Protocol
The IPS splits traffic flows to avoid congestion.
Congestion arises when too many connections are
set up through a certain section of a network (i.e.,
hot-spot).In order to avoid a hot-spot; The IPS splits
the traffic Flow just before the hot-spot. The IPS
requires periodic information exchanges among
neighbours. If IPS fails to reduce congestion, the
EPS algorithms activated. In the case of EPS
algorithm,
Source splits traffic flows among multiple paths
therefore reduces congestion. Therefore it is clear
that a combination of IPS and EPS improves
fairness in distributing load among nodes. Therefore
the throughput of a network improves.
G. PERFORMANCE EVALUATION:
Four metrics are evaluated in our study:
1) End-to-End delay: Represents the average time taken
to transfer a data packet from source to its
destination.We note that AODV has a better average

5. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
delay than AOMDV because if a link break, AOMDV
would try to find an a another from among the backup
routes resulting in additional delay to the packet
delivery time. In comparison, if a link break occurs in
AODV, the packet would not reach the destination
due to unavailability of another path from source to
destination. So AODV initializes the new route
discovery process for the same.
Fig 7 End-To-End Delay of Packets
Fig 8 End-To-End Delay of Packets
2) Packet Delivery Rate: Represents the ratio of the
number of received data packets at the destinations to the
number of data packets generated by sources. We note
that AOMDV has a better PDF value when compared to
AODV. This is because AOMDV can find an alternate
route if the current link has broken whereas AODV
initialize new route discovery process each time
Fig 9 Packet Delivery fraction
. Fig 10 Packet Delivery fraction
3) Routing Packet Overhead:
Routing packet overhead means the total number
of routing packets transmitted during the simulation.
We see that AOMDV has more routing overhead
that AODV. Due to AODV being a unipath routing
protocol, once a link breaks the packet delivery
along that route stops. But AOMDV use RREQ
packets. Hence AOMDV incurs more routing
overhead than AODV.

6. ISBN: 978-81-927147-0-7 National Conference on Instrumentation and Communication Engineering
(NACICE 2013)
Fig 11 Routing Packet Overhead
Fig 12 Routing Packet Overhead
Conclusion:
To improve the performance of network several routing
protocols can be extended by focusing the routing metrics.
This paper extends the AODV routing protocol. Here we
introduced new routing protocol named LB-M (Load
Balancing Multiple) routing protocol mainly focus on Load
balancing in multipath routing protocol which causes the
congestion which effect the performance of the network.
References:
[1] Survey of multipath routing protocols for mobile ad hoc net works
Mohammed Tarique a, Kemal E. Tepe b, Sasan Adibi c, Shervin Erfani b
[2] Load Balanced Routing Protocols for Ad Hoc Mobile Wireless
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Ze Cho, Kyung Pook National University
[3] Load-balancing in MANET shortest-path routing protocols- Oussama
Souihli, Mounir Frikha *, Mahmoud Ben Hamouda Graduate School of
Communications of Tunis (Sup’Com), El Ghazela Pole of Technology, Route
Raoued Km 3.5, 2083 Ariana, Tunisia
[4] Simulation and Comparison of AODV, DSR and AOMDV
Routing Protocols in MANETs-International Journal of Soft
Computing and Engineering (IJSCE) ISSN: 2231-2307, Volume-2,
Issue-3, July 2012, Manveen Singh Chadha, Rambir Joon, Sandeep
[5] Performance Evaluation and Comparison of AODV and
AOMDV-S.R.Biradar et al. / (IJCSE) International Journal on
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S. R. Biradar1, Koushik Majumder2, Subir Kumar Sarkar3,
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