Modeling the Pairwise Key Predistribution Scheme in the Presence of Unreliable Links

Modeling the Pairwise Key Predistribution Scheme

in the Presence of Unreliable Links

ABSTRACT:

We investigate the secure connectivity of wireless sensor networks under the random pairwise key predistribution scheme of Chan, Perrig, and Song. Unlike recent work carried out under the assumption of full visibility, here we assume a (simplified) communication model where unreliable wireless links are represented as independent on/off channels.We present conditions on how to scale the model parameters so that the network 1) has no secure node that is isolated and 2) is securely connected, both with high probability, when the number of sensor nodes becomes large. The results are given in the form of zero-one laws, and exhibit significant differences with corresponding results in the full-visibility case. Through simulations, these zero-one laws are shown to also hold under a more realistic communication model, namely the disk model.

EXISTING SYSTEM:

Many security schemes developed for general network environments do not take into account the unique features of WSNs: Public key cryptography is not feasible computationally because of the severe limitations imposed on the physical memory and power consumption of the individual sensors. Traditional key exchange and distribution protocols are based on trusting third parties, and this makes them inadequate for large-scale WSNs whose topologies are unknown prior to deployment. Random key predistribution schemes were introduced to address some of these difficulties. The idea of randomly assigning secure keys to sensor nodes prior to network deployment was first introduced by Eschenauer and Gligor. The approach we use here considers random graph models naturally induced by a given scheme, and then develops models naturally induced by a given scheme, and then develops the scaling laws corresponding to desirable network properties, e.g., absence of secure nodes that are isolated, secure connectivity, etc. This is done with the aim of deriving guidelines to dimension the scheme, namely adjust its parameters so that these properties occur.

DISADVANTAGES OF EXISTING SYSTEM:

To be sure, the full-visibility assumption does away with the wireless nature of the communication medium supporting WSNs. In return, this simplification makes it possible to focus on how randomization in the key assignments alone affects the establishment of a secure network in the best of circumstances, i.e., when there are no link failures. A common criticism of this line of work is that by disregarding the unreliability of the wireless links, the resulting dimensioning guidelines are likely to be too optimistic: In practice, nodes will have fewer neighbors since some of the communication links may be impaired. As a result, the desired connectivity properties may not be achieved if dimensioning is done according to results derived under full visibility.

PROPOSED SYSTEM:

In this paper, in an attempt to go beyond full visibility, we revisit the pairwise key predistribution scheme of Chan et al. under more realistic assumptions that account for the possibility that communication links between nodes may not be available. This could occur due to the presence of physical barriers between nodes or because of harsh environmental conditions severely impairing transmission. To study such situations, we introduce a simple communication model where channels are mutually independent, and are either on or off. An overall system model is then constructed by intersecting the random graph model of the pairwise key distribution scheme (under full visibility).

ADVANTAGES OF PROPOSED SYSTEM:

SYSTEM CONFIGURATION:-

HARDWARE CONFIGURATION:-

ü Processor             -        Pentium –IV

ü Speed                             -        1.1 Ghz

ü RAM                    -        256 MB(min)

ü Hard Disk            -        20 GB

ü Key Board            -        Standard Windows Keyboard

ü Mouse                  -        Two or Three Button Mouse

ü Monitor                -        SVGA

 

SOFTWARE REQUIREMENTS:

•         Operating system :         Windows XP.

•         Coding Language :         C#.Net.

•         Data Base             :         SQL Server 2005

•         Tool                     :         VISUAL STUDIO 2008.

REFERENCE:

Osman Yağan, Member, IEEE, and Armand M. Makowski, Fellow, IEEE “Modeling the Pairwise Key Predistribution Scheme in the Presence of Unreliable Links”-IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 59, NO. 3, MARCH 2013.