Alok Kumar Chowdhury

A novel strategy to discover Internet gateways in mobile ad hoc networks

Integrating nodes in a MANET to the Internet require either a connection to the Internet or they can connect to the Internet through the Internet gateways or servers. For the second case a node in a MANET has to find out the gateway or server to connect to the fixed nodes in the Internet. End to end packet delay and throughput are strongly dependent on the time needed to discover the gateways. A source node in a MANET can discover a gateway either by broadcasting a gateway discovery message or it may depend on periodic gateway advertisement messages from the gateways. The first one is renowned as reactive gateway discovery strategy and with this one a gateway in a MANET may receive the same gateway discovery message from different intermediate nodes. This paper presents a novel solution for connecting nodes in ad hoc network to the Internet. Here a gateway sends separate reply to the requestor for each request message having the same Broadcast ID it receives from that source in stead of sending only one unicast reply to the requestor. The AODV routing protocol has been used for routing in the MANET domain. We investigated our new strategy of gateway discovery in NS-2. Simulation results show that our one has better performance having lower delay and fewer packets drop.

A new source code repository for dynamic storing, browsing, and retrieval of source codes

Software reuse is a solution to reduce the costs of estimation, design, development, and testing. Reuse of source codes can release the coders from the time-killing botheration of doing the same coding again and again for same kind of software projects. If the proposed distribution format (Application→ Module→Class→Function→Sub-function) is followed while storing source codes, then it is easier to fulfill the requests for any level of source codes. In this paper, a source code repository system is proposed that dynamically distributes an application to its smallest level components and stores their information. Besides, it provides an interface to browse and retrieve the desired source codes. During dynamic retrieval, the desired source codes are merged together by a bottom-up integration method. Implementation shows that the proposed repository outperforms the other related research works with providing more features in simpler way.

An efficient algorithm for finding the control point of 3 rd order Bezier curve

This paper represents a modified algorithm to recover the control points of 3rd order Bezier curves more efficiently. It uses the two stage approximation learning algorithm with some modifications. In this regards, at 1st stage we modify the height (H) where we assume approximate 2nd and 3rd control points and at 2nd stage we modify the step size (δ) which moves the assumed control points towards the accurate control points. Experimental results demonstrate that our proposed method minimize the error level and reduce computation time for recovering the control points than the previous one. Our computer simulation proves the effectiveness of our proposed method.