Informatics Publishing Limited

R. Dhaya ¹, P. Subbulakshmi ¹, S. Vimal ¹, V. Jackins ¹

Affiliations
1 Department of IT in National Engineering College, Kovilpatti-628503, Tamilnadu, IN

Abstract

Blocking probability has been one of the key performance in all wavelength routed optical Networks. Routing and Wavelength Assignment (RWA) scheme and a wavelength converter placement algorithm are considered to be the two primary mechanisms for improving the performance. Existing Research demonstrated a dynamic RWA scheme for determining a route in presence of wavelength conversion. This paper introduces a weighted least-congestion routing and first-fit wavelength assignment (WLCR-FF) RWA algorithm for routing and wavelength assignment will be done with the help of simple heuristic wavelength converter placement algorithm called Minimum Blocking Probability First (MBPF) that considers both the distribution of free wavelengths and the lengths of each route jointly. This result better than Dynamic RWA since it considers the hop count of each route and free wavelength distribution jointly. The performance of the proposed algorithm has been compared with a wide variety of existing routing algorithms including static routing, fixed- alternate routing and least-loaded routing algorithms. The result implies that the proposed algorithm can achieve much better blocking performance in the wavelength conversion.

Keywords

Routing and Wavelength Assignment, Wavelength Routing, Wavelength Converter Placement.

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R. Dhaya ¹, S. Vimal ¹, R. Kanthavel ²

Affiliations
1 Department of IT, National Engineering College, Kovilpatti, Tamilnadu, IN
2 Department of CSE, Government College of Engineering, Tirunelveli, IN

Abstract

Wireless networking has been experiencing an enormous development in recent years and offers to both network operators and users an attractive flexibility and coverage. But wireless networks are more susceptible to attacks than wired networks. Hence it is visible that some form of security is required to prevent outsiders from exploiting in the form of eavesdropping, hampering the data and authentication denial in wireless networks. To overcome these security challenges, in the existing system Wired Equivalent Privacy (WEP) protocol is used to protect from attacks. But there are several serious security flaws in the protocol due to tools that can automate the cracking of WEP keys lead to a number of practical attacks that WEP fails to achieve its security goals. This paper proposes a secured wireless networks suitable for 802.11 standards using Wireless Protected Access (WPA) based on AES-CCMP (Advanced Encryption Standard-Counter Mode with Cipher Block Chaining Protocol). The result shows that the security issues in wireless networks have been solved.

Keywords

Wired Equivalent Privacy (WEP), Wireless Protected Access (WPA), AES-CCMP (Advanced Encryption Standard-Counter Mode with Cipher Block Chaining Protocol).

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R. Dhaya ¹, V. Sadasivam ², R. Kanthavel ³

Affiliations
1 Department of Information Technology, National Engineering College, Tamil Nadu, IN
2 Department of Computer Science and Engineering, Manonmaniam Sundaranar University, Tamil Nadu, IN
3 Department of Computer Science and Engineering, Government College of Engineering, Tamil Nadu, IN

Abstract

Bluetooth is a low power and cost-effective short range wireless network technology working in 2.4GHz ISM band. Bluetooth can be implemented either in piconet or Scatternet. In piconet the devices can communicate with each other forming a network with maximum of 8 nodes (1 master and 7 slaves). Two or more piconets can be connected through a common Bluetooth device (a gateway or bridge) to form a Scatternet. But the difficult thing is to achieve Quality of service (QoS) in Bluetooth particularly in the Scatternet. Quality of service refers to the efficient management of system resources, which includes the parameters like bandwidth, delay, jitter etc. This paper addresses guaranteed QoS in a Bluetooth scatternet by considering mainly two constraints namely Packet Loss and Waiting time .The above two constraints are met in a Bluetooth scatternet under high traffic congestion, which increases packet delay and causes channel wastage thereby affecting QoS. In the existing First In First Out (FIFO) scheme the slaves are served by the master in accordance with the arrival of the request offered by respective slaves in the form of 'first come first serve' technique. So a proposal to simulate a new priority based scheduling scheme like DST (Dynamic Scheduling Technique) has been implemented, which overcomes the pitfalls like packet loss, waiting time, and high congestion in the FIFO scheduling scheme. The results shows that the proposed DST scheduling that carries dynamic priorities for the requesting slaves by employing dynamic scheduling technique, which assures and guaranties the QoS parameters.

Keywords

Bluetooth, Sensor Network, Scatternet, Quality of Service, Dynamic Scheduling.

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R. Dhaya ¹, V. Sadasivam ², R. Kanthavel ³

Affiliations
1 Dept. of Information Technology, National Engineering College, Kovilpatti, Tamilnadu, IN
2 Dept. of Computer Science and Engineering, Manonmaniam Sundaranar University, Tirunelveli, Tamilnadu, IN
3 Dept. of Computer Science and Engineering, Govt. College of Engg., Tirunelveli, Tamilnadu, IN

Abstract

In the recent development of communication, Bluetooth Scatternet wireless is a technology developed for wideband local accesses. Bluetooth technology is very popular because of its low cost and easy deployment which is based on IEEE 802.11 standards. On the other hand Wireless Sensor Network (WSN) consists of large number of sensor nodes distributed to monitor an environment and each node in a WSN consists of a small CPU, a sensing device and battery. Mostly, the sensor networks are distributed in an inconvenient location and it is difficult to recharge often. So routing in WSN is an important issue to consume energy and as well as to increase the life of the network, since a routing protocol finds the path between sources and sink. Moreover it is a challenging task to schedule the data between nodes in a scatternet in a congestive environment. Here this paper presents a new scheduling method for point to multi- point routing in Scatternet sensor network and the new dynamic routing method designed is cluster-based with hierarchical routing. The efficiency of this method is also compared in terms of energy consumption and the results show that the proposed routing is an energy efficient one which simultaneously increases the lifetime of the network.

Keywords

Bluetooth, Dynamic Routing, Hierarchical Routing, Scatternet, Wireless Sensor Networks.

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