A Hybrid Approach to Reduction of Packet Loss in Wireless Sensor Network

Wireless sensor networks are spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data through the network to a main location The major role of sensor networks is sensing and delivering data to sink node, reliability is an important characteristic. However WSNs are associated with packet loss, which gets worse through multi-hop routing paths in wireless sensor networks, nodes near the destination have higher packet delivery performance. Numerous reasons for packet loss such as: signal attenuation due to the distance between the nodes, asymmetry in wireless communication links, non-uniform radio signal strength, wireless propagation effects (fading and multipath), interference due to hidden terminal problem, in addition to being  greatly affected by the deployment environment, and the behavior of wireless communication have been noticed. In an attempt to reduce packet loss via WSN, this research study proposes a combined approach of distributed storage system algorithm for wireless sensor networks coupled with Replacing Lost Packets (Packet Loss Concealment)  methods. . In an attempt to reduce packet loss via WSN, this research study proposes a combined approach of Modified distributed storage algorithm for wireless sensor networks (MDSA) coupled with Replacing Lost Packets (Packet Loss Concealment)  methods. During this study, a DSS was designed with both repetition code and regeneration code in case there is a link failure. Results from this study showed that for both codes the success probability of both theory and implementation correlate, while the regeneration code showed the highest success probability. And therefore it was chosen for further study. The implementation of regeneration code results showed that the increasing of field size also correlate with the increasing of success probability for both theory and implementation. The implementation of the proposed PLC results showed that showed that the proposed PLC algorithm improves significantly the quality of speech transmitted over an unreliable network with high packet loss rate. Though, the proposed PLC introduces additional delay which needs to be considered but the increased delay is often a necessary expense if the signal quality is a priority. Key words: Wireless Sensor Network,  Distributed Storage System algorithm, packet loss concealmen

Securing the IP Multimedia Subsystem with IPsec and HTTP Digest

Modern Telecommunication networks were combined from two communications: cellular networks and the Internet. The Internet Protocol Multimedia Subsystem (IMS) is the key element in the Modern Telecommunication networks architecture that makes it possible to provide wide range cellular access to all the services that the Internet provides. So, IMS is a great achievement in the communication world with advantage to maintain single communication platform for all but the big challenge is to maintain an adequate security level in this different network environment. IMS is based principally on IP protocol. Therefore, it inherits the security issues of IP networks. The IMS architecture is open, distributed and it has the advantage of being flexible in its implementation and deployment. This generates a variety of communication interfaces, which can make the system very vulnerable to attack. Add to that, the services offered on the IMS network must be provided by ensuring confidentiality and respect the privacy of users. Therefore, it is necessary to secure the IMS network at every level of its architecture including the final customer or subscriber device. Solutions like firewalls, anti-spy ware and antivirus systems failed to counter the emerging threats because they only target specific types of threats. In this study we are proposing security approach which is a Combination model composed of two protocols IPsec and HTTP digest