S. Lakshmi ¹, R. S. D. Wahida Banu ¹

Affiliations
1 Anna University, Chennai - 600025, Tamil Nadu, IN

Abstract

Background: Vanet the recent emerging technology in the recent industry has grabbed the attention with advanced techniques and extricate framework of sophisticated equipments. Initially absence of an infrastructure in this network has communication constraints for the nodes involved therein. Adding to this the dynamic topology makes the network more vulnerable for potential targets of security and reliability of data diffusion within these nodes. The communication standard i.e. 802.11p have some optional channel rejection in the Orthogonal Frequency Division Multiplexing in the Physical layer which motivated to work on the reliability methods of data dissemination. Methods: To start with the hidden terminal issues of these networks have to be addressed which can be resolved by frame capture. This frame capture quality in turn is determined by the Contention window of the Physical layer. Hence an adaptive mechanism that involves forward Error correction (AFEC) which helps to overcome packet losses in an efficient way in midst of channel fluctuation, burst packet loss. The results are simulated in NS2 (2.34) with static packet size of 512 bytes. Findings: The experimental results demonstrated that the FEC mechanism is more adaptive in adjusting and controlling the data redundancy across the network for static and dynamic channel fluctuations. The redundancy rate was further reduced with an adaptive technique on the Contention Window size, which had considerable effects of every transmission on the delay, through put and jitter. The centralized FEC algorithm is set on an adaptive platform where each vehicle updates its back off window size at the end of each Observation Time depending on the priority of the message received. The feasible part of this algorithm is that it can be implemented on the MAC layer, which has a Reception Module. Consequently, the proposed mechanism under various network conditions performs well in terms of QoS for emergency messages than the conventional methods for a less volume of data. Application/Improvements: The algorithm can be analyzed from a traffic scenario of two-way highway and rural areas. The progress of the work can also be carried out for multimedia messages.

Keywords

Contention Window, Data dissemination, Forward Error Correction Mechanism, QoS of message, Vanets

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R. Menaka ¹, R. S. D. Wahida Banu ², B. Ashadevi ³

Affiliations
1 Anna University, Sarder Patel Road, Old Highways Building, Guindy, Chennai - 600 025, Tamil Nadu, IN
2 GEC, NH 7, Banglore Highways, Salem - 636011, Tamil Nadu, IN
3 CS Department, Kunthavai Nachiar Govt. Arts College for Women, Arulananda Nagar West Extension, Thanjavur -613007, Tamil Nadu, IN

Abstract

Web service is the technology tied up with SOAP, UDDI and WSDL of XML format, so web services searching based on XML keyword become essential. By systematic monitoring it has been observed that internet communication is less protected than intranet communication. The transaction exchange held through internet in web which is one among the distributed application is embodied to different vulnerability. In distributed environment, messages and data are exchanged as Extensible Markup Language (XML) format for its vast compatibility in transit. For facing the competitive environment, any business teams have to find their suitable web services among the bulk services prevails in market. In apt to this, survey has been made with different searching techniques and way to boost the security container filled with access permitted service alone. Our research work on XML based Web security is concentrated on providing the privacy, certification and integrity. We investigate the way to regulate and insist the security by applying XML Encryption and Signature for data or messages in transaction and in storage form. It also proves the performance improvement in searching data from vast resources, if so security constraint is provided. Search Engines Optimization (SEO) is enhanced with parsing the descriptive tags rather than chaos data. Traders need not have prior knowledge of web farms lifecycle and its protection.

Keywords

BPEL, Multi-Tier Security, User Satisfy Profile, Web Service, XML Cryptography

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