Communications in wireless networks has been facilitating numerous emerging applications that require packet delivery from one or more senders to multiple receivers. Communications are susceptible to various kinds of attacks due to insecure wireless channels. Communications in wireless networks remains a challenging and critical issue. This paper presents recent advances in security requirements and services in communications in wireless networks. Wireless networks are being used in many commercial and military applications to collect event driven and real time data. Deployment nature of networks makes them vulnerable to security threats. Due to the resource limitations traditional security measures are not more enough to keep safe the nodes. Research in network security domains has produced several security solutions. In this paper we have observed security mechanisms. We have studied these security mechanisms with respect to packet overheads and compared the packet transmission time, average latency and energy consumption. The comparison shows that the packet overheads are lesser as compared to other schemes. It have been observed that packet delivery ratio decreases when we increase number of nodes while energy and latency increases.

Software testing plays an important role during the software developing period. Any saving on software test will significantly reduce the total cost of software. The key point of this paper is to build a software testing process with the cost control management and to make tradeoffs between the software quality and the software cost. Typical software testing model are analysed and compared. A Quality controlled 3-D testing model is introduced. The model combined with software test process, software quality cost and the testing type. The computational formula is defined to calculate software quality cost. A software quality balance law is introduced to balance control and failure cost. By adjusting software testing method and strategy, organization can reach the objective of the best balance between software quality and the software cost. The result shows an optimistic point that will prove the accurate of the model and the law introduced.