29-03-2012, 04:40 PM
SECURE ROUTING FOR MOBILE AD HOC NETWORKS
10.1.1.81.4598.pdf (Size: 210.75 KB / Downloads: 35)
ROUTING IN MOBILE AD HOC NETWORKS
Routing in mobile ad hoc networks faces additional problems
and challenges when compared to routing in traditional wired
networks with fixed infrastructure. There are several wellknown
protocols in the literature that have been specifically
developed to cope with the limitations imposed by ad hoc networking
environments. The problem of routing in such environments
is aggravated by limiting factors such as rapidly
changing topologies, high power consumption, low bandwidth,
and high error rates [2]. Most of the existing routing protocols
follow two different design approaches to confront the inherent
characteristics of ad hoc networks: the table-driven and the
source-initiated on-demand approaches.
TABLE-DRIVEN AD HOC ROUTING PROTOCOLS
Table-driven ad hoc routing protocols maintain at all times
routing information regarding the connectivity of every node
to all other nodes that participate in the network. Also known
as proactive, these protocols allow every node to have a clear
and consistent view of the network topology by propagating
periodic updates [2]. Therefore, all nodes are able to make
immediate decisions regarding the forwarding of a specific
packet. On the other hand, the use of periodic routing messages
has the effect of having a constant amount of signaling
traffic in the network, totally independent of the actual data
traffic and the topology changes.
Destination-Sequenced Distance-Vector Routing —
DSDV is a table-driven routing protocol based on the Bellman-
Ford algorithm [7]. The DSDV protocol can be used in
mobile ad hoc networking environments by assuming that
each participating node acts as a router. Each node must
maintain a table that consists of all the possible destinations.
In more detail, an entry of the table contains the address
identifier of a destination, the shortest known distance metric
to that destination measured in hop counts, and the address
identifier of the node that is the first hop on the shortest path
to the destination [5].
Authenticated Routing for Ad hoc Networks (ARAN) —
The Authenticated Routing for Ad hoc Networks (ARAN)
protocol, proposed in [25], is a stand-alone solution for securing
routing in ad hoc networking environments. ARAN utilizes
cryptographic certificates in order to achieve the security
goals of authentication and non-repudiation.
SYMMETRIC CRYPTOGRAPHY SOLUTIONS
This category presents solutions that rely solely on symmetric
cryptography to secure the function of routing in wireless ad
hoc networks. The most commonly utilized mechanisms are
hash functions and hash chains. A one-way hash function is a
function that takes an input of arbitrary length and returns an
output of fixed length [26].
CONCLUSION
This survey has presented the best known protocols for securing
the routing function in mobile ad hoc networks. The analysis
of the different proposals has demonstrated that the
inherent characteristics of ad hoc networks, such as lack of
infrastructure and rapidly changing topologies, introduce additional
difficulties to the already complicated problem of
secure routing. The comparison we have completed between
the surveyed protocols indicates that the design of a secure ad
hoc routing protocol constitutes a challenging research problem
since already existing generic solutions, such as IPsec,
cannot be successfully applied. Additionally, the flexibility of
ad hoc networks enables them to be deployed in diverse application
scenarios.