Performance Comparison of Multipath and Unipath Routing in Static Scenarios
Zheng Wan
School of Information Technology
Jiangxi University of Finance and Economics
Nanchang, China, 330013
e-mail: cloudcity66@yahoo.com.cn
Abstract—In the past decade, multipath routing has been
proposed to provide reliability for mobile ad hoc networks
(MANETs). As wireless mesh networks become more and more
popular, performance evaluation of different routing
algorithms is required in static scenarios. Performance
comparison between unipath routing and multipath routing is
conducted in this paper. From the simulation results we find
that multiple paths should not be employed simultaneously to
avoid interference among paths. Researchers should focus on
how to find the path with the best quality.
Keywords- Multipath routing; unipath routing; performance
comparison; MANET; IEEE 802.11
I. INTRODUCTION
Multipath routing has been proposed to provide
reliability for mobile ad hoc networks (MANETs). As for
MANETs, they often consist of a collection of wireless
mobile nodes which dynamically exchange data among
themselves without the reliance on a fixed base station or a
wired backbone network. MANET nodes are typically
distinguished by their limited power, processing, and
memory resources as well as high degree of mobility. In such
networks, the wireless mobile nodes may dynamically enter
the network as well as leave the network. Due to the limited
transmission range of wireless network nodes, multiple hops
are usually needed for a node to exchange information with
any other node in the network. Thus routing is a crucial issue
to the design of a MANET.
Routing protocols in conventional wired networks are
usually based upon either distance vector [1] or link state
routing algorithms [2]. Both of these algorithms require
periodic routing advertisements to be broadcast by each
router. These conventional routing algorithms are clearly not
efficient for the type of dynamic changes which may occur
in an ad-hoc network.
Work on single path (or unipath) routing in MANETs has
been proposed in [3] [4]. Multipath routing allows the
establishment of multiple paths between a single source and
single destination node. Multipath routing is typically
proposed in order to increase the reliability of data
transmission (i.e., fault tolerance) or to provide load
balancing.
With the development of wireless technology, more and
more wireless standards were proposed. Compared to
MANETs, wireless mesh networks (WMNs) are relatively
static networks with multihop characteristics. Is multipath
routing suitable for such a static network? In this paper we
examine the performance of multipath and unipath routing in
static scenarios with different settings and give some
conclusions.
The rest of the paper is organized as follows. In Section 2,
we provide an overview of studies on multipath routing. We
discuss the performance comparison between multipath and
unipath routing in Section 3. Finally in Section 4, we provide
the conclusion.
II. R
ELATED WORK
Standard routing protocols in ad hoc wireless networks,
such as AODV and DSR, are mainly intended to discover a
single route between a source and destination node.
Multipath routing consists of finding multiple routes between
a source and destination node. These multiple paths between
source and destination node pairs can be used to compensate
for the dynamic and unpredictable nature of ad hoc networks.
Previous work extends the Ad hoc On-demand Distance
Vector (AODV) routing and dynamic source routing (DSR)
protocols to their multipath versions, but a few of them
consider path coupling in the routing protocol design. Split
multipath routing [5] is proposed to build an alternative path
that is maximally disjoint from the shortest delay path.
Unfortunately, path interference is not considered. As an
extension to AODV, AODV-Multipath (AODVM) [6] is
able to establish multiple node-disjoint paths. Marina and
Das proposed AOMDV [7] to compute loop-free and link-
disjoint paths. Incorporating the path accumulation feature of
DSR into the extension of AODV, the routing protocol in [8]
discovers multiple node-disjoint paths with low overhead.
Nasipuri et al. extended DSR to support multipath routing
[9]. CHAMP [10], which is based on DSR, uses cooperative
packet caching and shortest multipath routing to enhance
robustness against link breakdowns.
Raghunathan and Kumar [11] proposed a distributed load
adaptive multipath routing protocol that converges to the
Wardrop equilibrium. When the protocol reaches the
equilibrium, all established paths between the source and
destination have the same delay, which is less than that of
any unused paths.
In [12], algorithms used to discover link-disjoint multiple
paths and braided multiple paths are proposed. Based on the
per-hop channel error rate, which is assumed to be constant
across the entire network, the number of outgoing paths is
2012 Third International Conference on Networking and Distributed Computing
2165-5006/12 $26.00 © 2012 IEEE
DOI 10.1109/ICNDC.2012.29
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