Call for Comming Issue

Volume 1, Issue 3 August 2013

S.No. Title Page No.
Study of Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM)
Author: Sushant S. Patil
Abstract: Recently, Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM) has been seen as a possible candidate for long-standing time optical transmission. it's thanks to OFDM technique that was established as an efficient resolution for mitigating chromatic dispersion (CD) effects in optical communication systems. The CO-OFDM systems of 40Gb/s and one hundred Gb/s per channel will use structure mapping to extend spectral potency. This paper presents associate degree implementation of OFDM transmitter and receiver victimization QPSK and 16-QAM mapping. The transmitter is to come up with the orthogonal signals for optical modulators, and therefore the receiver find the signals when the optical receiver then to recover orginal signals. The system consists of Matlab simulation and FPGA-based implementation. Simulink and hardware models bestowed square measure ascendible to higher speed permitting potential implementation in electronic processors for advanced optical communications.
An approach for detection of Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks
Author: Rajesh Mathani
Abstract: Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks have emerged as a well-liked suggests that of inflicting assortment specific overhaul disruptions, typically for total periods of instance. The relative ease and low prices of initiation such attacks, supplemented by the current lean satiate of any possible defense methodology, have created them one in every of the highest threats to the web centre of population today. Since the rising attractiveness of web-based applications has junction rectifier to quite ton of great services being provided over the web, it's vital to observe the network transfer thus on stop hateful attackers from depleting the assets of the network and denying services to rightful users. the foremost necessary drawbacks of the presently existing defense mechanisms and propose a new-fangled mechanism for defensive a web-server against a DDoS attack. within the projected mechanism, incoming traffic to the server is usually monitored and a few irregular rise within the arriving traffic is at once detected. The detection rule is predicated on an applied mathematics analysis of the arriving traffic on the server and a sturdy suggestion testing structure. whereas the detection procedure is on, the sessions from the rightful sources don't seem to be discontinuous and therefore the load on the server is renovated to the same old level by overcrowding the traffic from the offensive sources. The correct modules use multifarious detection logic and thus involve extra overhead for his or her execution. On the opposite hand, they need terribly large detection accuracy. Simulations approved on the projected mechanism have made results that show potency of the projected defence reaction against DDoS attacks.
Power Adaptation rule is enforced beside convolution codes for various rates
Author: Md. Imran Hashan
Abstract: Coding plays vital role in wireless transmission because the most significant theme for communication of cropped pictures over wireless channels, because of its ability to modify numerous channel qualities and to approach the theoretic limits of transmission rates. During this paper, most Power Adaptation rule is enforced beside convolution codes for various rates. This projected technique shows higher performance compared to traditional Power Adaptation rule combined with convolution codes for various rates. The projected theme works iteratively to seek out the best combination of committal to writing and power transmitted for individual bits to reduce the mean sq. error for higher cropped image excellence. it's shown that bits of major importance i.e most important bits must always be coded and allotted most of the ability transmitted. However, different bits of less significance is also transmitted with less power. this is often done whereas maintaining the typical power per bit at identical level. Code rate ½ showed higher performance compared with different codes.
The functioning of MIPS processor in register direct & immediate mode
Author: Jigar Ratnakar Mohan
Abstract: This paper targets the implementation of a million instructions per second (Microprocessor while not Interlocked Pipeline Stages) computer architecture (Reduced Instruction Set Computer) Processor via VHDL (Very high speed microcircuit Hardware Description Language) style. The goal of this paper is to boost the simulator primarily based approach by integration some hardware style & simulating them in pipelined (3 level) & non-pipelined modes so on assess the performance of the processor in every of the modes.





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