Wireless Sensor Networks Analysis for Connectivity and Reliability Enhancement رسالة ماجستير

Abstract

Because of the huge growing in wireless sensor networks (WSN) it became an important research area field. Wireless sensor networks are small devices that have restricted power energy and memory. In general they are easy reachable from the outside world they are also easy to attack from the outside attackers. So there are many methods are built to prevent these attacks. So preventing outside attackers from attacking the WSN is a must, security measures are one of the important technique that each WSN must have. One of the most popular attacks are the Jamming attacks, they attend to prevent nodes from transforming data or send false one. This type of attacks has many attacking types and also many preventing technique also. In this thesis securing WSN is studied to provide dependable, robust and lightweight security mechanisms that guarantee the system ability to be strong against foreign attacks. Different types of security attacks and the appropriate security mechanisms are deeply discussed, taking in to account the resources constraints in WSN. Our proposed model investigates the combination of Direct Sequence- Code Division Multiple Accesses (DS-CDMA) with Orthogonal Frequency Division Multiplexing (OFDM) and Frequency Hopping (FH) VI as a promising anti-jamming technique in wireless sensor networks (WSN). The DS-CDMA component provides user discrimination based on coding at the same carrier frequency and simultaneously. The OFDM component removes Inter-Symbol Interference (ISI) and provides resistance to multipath effect. The FH component solves the near-far problem inherent in DS-CDMA