High-Altitude Platforms (HAP) is an emerging technology for mobile broadband communications and is capable of providing many advantages compared to conventional terrestrial and satellite systems. On the other hand, positional instabilities of HAP affect the system performance greatly. In this paper, a main problem concerning the rotation motion or yaw-shiftof HAP is described, analyzed, and its impact on the handover of cellular systems is also investigated. The total handover due to both user mobility and platform rotational positional instability is discussed and determined. An expression for the number of calls subjected to handover is deduced where it will be a function of users' density and their distribution in the cell, platform angular shift due to rotation, cell geometry, and number of active calling users. The analysis of this number shows the serious effects of the yaw-shift instability on the system performance.

Research in Wireless Sensor Networks (WSNs) has made a significant progress recently, especially the area of key management, which plays a central role for protecting group communication in sensor networks. In sensor networks, the data are crucial and have to keep secrecy in data communication. To achieve data confidentiality, adversary should not have access to the group communication. Therefore due to the limited memory resources and energy constraints of sensor nodes, reducing the communication and storage overhead, and improving the resilience against the node capture attack become a must.

In this paper we propose An Efficient Group Key Management using Symmetric Key and Threshold Cryptography for Cluster based Wireless Sensor Networks (EGKMST). The proposed scheme considers a hierarchical cluster structure of sensor network and adopts the pair-wise key management and group key management based on threshold key cryptography to generate and to distribute the keys efficiently within a cluster and updates periodically keys. By this way EGKMST provides continuous transmission security and avoids dangerous attacks from malicious nodes and mitigate the node compromise attack in WSNs communication. The security and performance analysis illustrate that EGKMST scheme achieves the requirement of group communication and provides efficient security with low communication cost, low memory overhead and energy saving compared with some existing key management schemes.

A Smart Home is an emerging technology, where the electronic devices are controlled automatically based on the occupants activities. The pervasive computing plays a vital role in the smart home environment, which provides the computer-based service to human beings anywhere and anytime. However, when discussing smart home of the future, related studies have focused on providing middleware. The middleware acts as a interface between human beings and the smart devices. In this paper, we have proposed a generic middleware model for smart home that enables interaction between human being and devices and also between various devices based on the context identified in the environment.

Today, XML has become one of the important formats of saving and exchanging data. XML structure flexibility enhances its use, and the content of XML documents is increasing constantly. As a result, since file management system is not able to manage such content of data, managing XML documents requires a comprehensive management system. With the striking growth of such databases, the necessity of accelerating the implementing operation of queries is felt. In this paper, we are searching for a method that has required ability for a large set of queries; the method that would access fewer nodes and would get the answer through a shorter period of time, compared to similar ways; the method which has the ability of matching with similar ways indicator, and can use them to accelerate the queries. We are seeking a method which is able to jump over the useless nodes and produces intermediate data, as compared to similar ones. A method by which nodes processing are not performed directly and automatically through a pattern matching guide.

Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. Cloud computing recently emerged as a promising solution to information technology (IT) management. IT managers look to cloud computing as a means to maintain a flexible and scalable IT infrastructure that enables business agility. As much as the technological benefits, cloud computing also has risks involved. In this paper Cloud Computing security challenges will be discussed and proposed many new recommendations to increase security and trust also maintaining privacy.

Intrusion-detection systems (IDS) aim at de-tecting attacks against computer systems and networks or, in general, against information systems. Its basic aim is to protect the system against malwares and unauthorized access of a network or a system. Intrusion Detection is of two types Network-IDS and Host Based- IDS. This paper covers the scope of both the types and their result analysis along with their comparison as stated. OSSEC (HIDS) is a free, open source host-base intrusion detection system. It performs log analysis, integrity checking, Windows registry monitoring, rootkit detection, time-based alerting and active response. While Snort (NIDS) is a lightweight intrusion detection system that can log packets coming across your network and can alert the user regarding any attack. Both are efficient in their own distinct fields.

Present research work describes advancement in standard routing protocol AODV for mobile ad-hoc networks. Our mechanism sets up multiple optimal paths with the criteria of bandwidth and delay to store multiple optimal paths in the network. At time of link failure, it will switch to next available path. We have used the information that we get in the RREQ packet and also send RREP packet to more than one path, to set up multiple paths, It reduces overhead of local route discovery at the time of link failure and because of this End to End Delay and Drop Ratio decreases. The main feature of our mechanism is its simplicity and improved efficiency. This evaluates through simulations the performance of the AODV routing protocol including our scheme and we compare it with HLSMPRA (Hot Link Split Multi-Path Routing Algorithm) Algorithm. Indeed, our scheme reduces routing load of network, end to end delay, packet drop ratio, and route error sent. The simulations have been performed using network simulator OPNET. The network simulator OPNET is discrete event simulation software for network simulations which means it simulates events not only sending and receiving packets but also forwarding and dropping packets. This modified algorithm has improved efficiency, with more reliability than Previous Algorithm.

In today’s world, overall global mostly depend on technologies for their information storage and transactions. But this frequent use of online technologies make the data stored exposed to the risk of attacks towards the data in the form of intrusion. In order to save our data from these attacks, the researchers had implemented a concept called intrusion detection system, with the help of detection technology the users can prevent their critical data from different kind of attacks. As we know that there are lots of intrusion detection system in market which are either open source and some of them are commercial. Although the number is very high but there is no such classification available in research literature which will help user or security professionals. In this paper we will present a good and elaborated classification based on various parameters which will help the researchers and security professional to understand the category. The paper will also provide a brief detail of those categories which will give idea of representing the intrusion detection techniques.