BUJICT 2014

11-18

Authors: Zuhaib Ashfaq Khan, Muhammad Hasanain Chaudary and Juinn-Horng Deng

This article discusses the performance analysis of a network coded relay network. The relay nodes operate in decode-and-forward (DF) mode. The channels are modeled as Rayleigh, Nakagami-m and Rician fading. The overall system performance is improved by using the Alamouti coding scheme. The closed-form expressions of mo me n t generating function (MGF) are obtained over various fading channels. The system performance is analyzed in terms of SER and outage probability. MGF based approach is followed to derive the closed-form expressions of SER for MPSK modulation schemes. The derived expressions also present the diversity order. The simulation and theoretical results are produced to authenticate accuracy of the system.

23-30

Authors: Hla Myo Tun, Hein Thura Aung and Zaw Min Naing

Mobile IP is one of the solutions for connecting mobile nodes without breaking ongoing communications. Mobile IP uses two IP addresses: one is home address and another is care-of address which is used when the mobile node is moved to another network. Although original mobile IP can support seamless roaming, it still has many problems such as packet loss during handoff and handoff latency. Those problems usually effect on the performance of mobile IP. In mobile IP regional registration, a Gateway Foreign Agent (GFA) is added at just one hop away from foreign networks. Registration process within the same domain does not need to connect with the home agent and the GFA performs as local home agent for the mobile node. In Fast Optimized Smooth Handoff (FOSH), the foreign agents share information of mobile nodes by sending binding updates to each other. By sending registration request message to all entries in the Cache, the mobile node can perform an early registration. In our proposed method, FOSH mechanism is applied to mobile IP Regional Registration in order to reduce the number of packet loss that is lost at foreign agents during handoff. ‘Network Simulator Version 2’ (NS2) is used to implement the proposed method and output trace file is manipulated in order to evaluate the performance of mobile IP in terms of packet loss and packet delay. The number of hops between the home agent and the mobile node and the speed of the mobile node is varied as the functions of the performance of the mobile IP in terms of packet delay and number of packet loss.

39-45

Authors: Syeda Binish Zahra and Mohsin Nazir

Software estimation process is still a complicated procedure for estimators. It is the responsibility of software project manager; that he effectively handles the budget problems and should manage whole work within given time slot. Lot of estimation models, techniques and approaches are used; but none of them be able to provide 100% accuracy in time, in cost or in any other estimation factors. But expert suggests if we use estimation techniques in proper manner than estimation process become easier or reliable. This paper comparing the software estimation approaches in depth, and makes the selection of appropriate estimation model easier.

51-56

Authors: Zeeshan Ali, Muhammad Khalid and Shakil Ahmad

In this paper the performance and design comparison of conventional fuzzy logic controller (CFLC) and the single input fuzzy logic controller (SIFLC) to regulate the output voltage of the buck power converter has been proposed. The CFLC is the two term controller it has two inputs error and the change of error it uses the 2-dimensional rule table, by using the idea of the signed distance method in the designing of the SIFLC, the 2-dimensional rule table for the CFLC can be converted into 1-dimensional rule table or linear control surf . The important feature is by means of signed distance method the two inputs CFLC can be converted into SIFLC with no significant change in the performance also as the rule table is reduced so SIFLC takes less time to execute its algorithm. To demonstrate that the performance of both controllers CFLC and SIFLC are identical a MATLAB simulation is carried out.

64-69

Authors: Muhammad Zakarya, Zahoor Jan, Imtiaz Ullah, Nadia Dilawar and Uzm

Distributed denial of service (DDoS) attacks on the Internet in general and particularly in Grid computing environment has become a visible issue in computer networks and communications. DDoS attacks are cool to provoke but their uncovering is a very problematic and grim task and therefore, an eye-catching weapon for hackers. DDoS torrents do not have familiar characteristics therefore, currently existing IDS cannot identify and discover these attacks perfectly. Correspondingly, there implementation is a puzzling task. In practice, Gossip based DDoS attacks detection apparatus are used to detect such types of attacks in computer networks, by exchanging stream of traffic over line. Gossip based techniques results in network overcrowding and have upstairs of superfluous and additional packets. Keeping the above drawbacks in mind, we have proposed a DDoS detection and prevention mechanism in that has the attractiveness of being easy to adapt and more trustworthy than existing counterparts. We have introduced entropy based detection mechanism for DDoS attack. Our proposed solution has no overhead of extra packets, hence resulting in good QoS. Once DDoS is detected, any prevention technique can be used to prevent DDoS in Grid environment. In this paper we are going to extend our idea. A confirmation mechanism is introduced herewith.