Uma Bhattacharya

Applications of wireless sensor network in Intelligent Traffic System: A review

An Intelligent Traffic System (ITS) involves a much closer interaction between all of its components: drivers, pedestrians, public transportation and traffic management systems. Adaptive signal systems, driver advisory and route planning and automated vehicles are some of the goals set up to increase the efficiency of actual systems. Vehicular network became one of the most active and emerging fields of research during last decade. Its use in diversified applications (for example safe driving, congestion avoidance, parking assist system and even entertainment) will soon bring revolutionary changes in transportation system. In this paper we have reviewed applications of wireless sensor network towards developing an efficient system to control and manage smooth traffic flow.

A CRT based Encryption Methodology for Secure Communication in MANET

MANETs are well known for their flexibility and ease of communication. The communication is purely based on trust, without any need of authentication. This often leads to insecure communication, causing information tampering. The traditional means of security are not sufficient to safeguard against the inherent dangers of MANET. Researchers around the world are working in this issue. The preferred mode of securing data is through encryption. The process of encryption however is complex enough to increase the computational overhead. This paper proposes a secure encryption strategy using Chinese Remainder Theorem for shielding data from unauthorized access. The paper also includes a comparison of proposed method with existing methods General Terms CRT based key generation and secure route detection for secure communication.

A new scalable optimal topology for multi-hop optical networks

This paper presents a scalable optimal logical topology scale-net for multi-hop optical networks based on de Bruijn graph, a regular non-scalable one with simple routing strategy. In addition to its scalability property, this new topology maintains the simplicity in routing as in de Bruijn graph while keeping its diameter same throughout the insertion of nodes as that in a de Bruijn graph where the diameter is of logarithmic value of its number of nodes. Also, perturbation in the network is maintained at a very low level, while inserting a node in the network. Simulation results also show a reasonable average hop distance between any source destination pair of the topology developed.

A survey on regenerator Placement Problem in translucent optical network

Recent research work reveals that the performance of translucent optical network is very near to fully opaque network but much better than transparent network in terms of cost and overall blocking. A translucent optical network is capable to reduce the network design cost as well as routing cost by dividing each light-path into one or limited number of segments by selecting some nodes as regenerator nodes in the network which helps retain the original optical signal quality. Minimization of the total number of placed regenerators and selection of their best locations to establish a path between every pair of source-destination nodes in the network are the main objective of translucent optical network design. This is known as regenerator Placement Problem (RPP) which has been proved to be NP-complete. This paper will provide an overview of various research works and heuristics developed on RPP along with their advantages, drawbacks and performance.

A New Scalable Topology for Multihop Optical Networks

A new scalable logical topology for multihop optical networks has been presented in this paper based on de-Bruijn graph. The de-Bruijn graph having simple routing property is a regular non-scalable logical topology having diameter to be of logarithmic value of number of nodes. The proposed topology adds the advantage of scalability over those in de-Bruijn graph, keeping perturbation in the network to a very low level during insertion of nodes, at the cost of marginal variance in degree of the network.

Clar: A Novel Cluster Oriented Agent Based Routing Protocol for Manet

Abstract In this paper we propose a novel algorithm CLAR to build an agent based routing protocol using ACO technique in cluster based mobile ad-hoc networks. Clustering makes possible hierarchical routing in which paths are recorded between cluster-heads instead of nodes. This reduces routing overheads. Presence of an unstable and non-reliable cluster-head degrades the performance of the network since cluster-heads of the network take active role in routing messages between a source destination pair. The proposed algorithm chooses the most reliable and stable node as cluster-head depending on four criteria i.e.: stability, battery power, degree, and trust value of the node. It also uses a multiagent based routing algorithm to generate load balanced routes between source and destination in cluster-based network. Performance of CLAR is compared with other existing efficient algorithms such as AODV, CBRP, Wu & Li’s Algorithm, dominating set based clustering algorithms, agent-based algorithms named as SACO and MALBACO. Simulation results prove that the proposed protocol combines merits of both clustering approach and agent based approach and provides efficient packet delivery even in the presence of high load in the network

New strategies for static routing and wavelength assignment in de Bruijn WDM networks

Blocking probability has been one of the important parameters for performance analysis in the design of wavelength routed WDM networks. Existing research has proved that the way in which Routing and Wavelength Assignment (RWA) is carried out significantly affects wavelength conversion requirements, which directly affects the blocking performance. In this paper we propose two new static Wavelength Assignment (WA) strategies namely NRNWA (Nearest Request Next Wavelength Assignment) and LDWA (Link Dependent Wavelength Assignment) for WDM networks based on de Bruijn graphs. We compare these proposed strategies with our earlier static RDWA (Ring Dependent Wavelength Assignment) strategy and the well-known FFWA (First Fit Wavelength Assignment) strategy. For request routing, we consider our earlier CRR (Congestion Reduced Routing) and the well-known SRR (Shift Register Routing) algorithms. We combine the various routing and the WA strategies mentioned above in pairs to form eight static RWA strategies and compare the blocking performance of the eight strategies for different de Bruijn graphs. Performance comparison shows that the proposed strategies perform better than the earlier ones.

A Novel Distributed Clustered Approach towards Building an Agent Based Routing Topology for MANET

The problem of routing is a complex one in case of mobile ad hoc networks due to the dynamic topology. Clusterization is an efficient means of increasing the efficiency of a MANET. A study of several clustering algorithms has lead to the observation that stable, secure cluster head selection increases lifespan and security of the network. The current state of art also relies heavily on ant colony optimization technique for finding the optimum shortest route in case of MANET. This paper proposes an agent based routing protocol for routing packets in a cluster based MANET. The algorithm is proposed to work in a distributed manner, using the concept of dominating set of mobile nodes. The selection of cluster head is determined on the basis of parameters such as connectivity, stability and residual battery power.

Congestion optimized routing in unidirectional de Bruijn WDM networks in presence of node faults

In this paper the problem of reducing congestion in WDM networks based on unidirectional de Bruijn graphs has been addressed in the presence of node faults. We propose a polynomial time routing algorithm for reducing congestion and analyze its time complexity. Congestion is defined as the maximum of the number of lightpaths propagating through a link over all links in the network. Congestion optimization is important as it leads to optimization of the load λmax an important parameter of a lightpath request. Results of the algorithm are shown for de Bruijn networks with various sizes of lightpath requests both in the presence and absence of node faults. Finally we evaluate the performance of the algorithm by comparing the results with those from two other strategies, the greedy routing algorithm and the graph search routing algorithm. Comparisons show that the proposed routing algorithm is the best amongst the three both in the presence and absence of node faults.

MoveFree: A ubiquitous system to provide women safety

With surveys of what is happening around us, it is beyond any argument to state that women are not safe enough to move freely alone. It is high time for the women to give a good retort to the society and raise their voice against the crimes that are taking place regularly. Pervasive computing with its omnipresent nature is emerging with a revolutionary approach towards technological growth. Anything and everything of the surroundings can be made to act as a computing device using the concept of pervasive computing. This paper makes use of the ever-present nature of pervasive computing to provide security to women. The work of this paper aims at designing a pervasive system comprising of a wearable computer that will act as a guardian angel for women in danger. The design of the system makes use of body area sensors, Bluetooth communication, GPS, SMS and MMS, Internet connection and mobile database system. A machine learning approach based on supervised classification is used to determine whether a woman is in danger. A prototype of the system is implemented in android.