Wireless technologies and services have been witnessed a rapid growth in the past few years, due to this development, spectrum scarcity and shortage has become a major concern, several spectrum portions of the static allocated licensed bands are under-utilized, Cognitive radio networks (CRNs) the most encouraging solution in enhancing the spectrum utilization by providing licensed spectrum portions to unlicensed users, however due to nature of these networks, CRNs are exposed to different types of security threats and attacks from different malicious users, which can affect the network availability and performance, in this paper we presents the survey for the resource allocation in wireless networks, and improve the security system.

During the past few years renewable energy sources have received greater attention and considerable efforts have been made to develop efficient energy conversion and utilization system. The major goals of these approaches are to have reduced environmental damage, conservation of energy, exhaustible sources and increased safety. The vision of a Smart Grid includes technologies that enable the efficient integration of intermittent renewable energy sources (such as wind or solar energy) and electric vehicles, and will reduce demand by allowing consumers to better manage how electricity is used, stored, and delivered. Many countries are currently making massive investments on smart grid research and development, In this paper we presents the hybrid model for the renewable energy sources including wind energy for the whole day and solar energy sources for the day time only.

Nowadays, the share of electricity produced by Renewable Energy Sources (RES) is rapidly growing, However, a further expansion of wind and solar power plants is going to become more and more challenging in the future, as one of the main drawbacks of solar and wind sources is their intermittent and variable nature, which can cause frequency misbalances and serious problems in grid management. A promising option for sustainable power generation is the integration of different solar power plants, such as photovoltaic systems (PV) and concentrating solar power (CSP) plants. The solar-wind-based system mainly composed of a photovoltaic array, a wind turbine and a battery bank. In this paper we present the study of various renewable sources of energy, in future we plan to design and implement a hybrid system or model which improve the performance of system and remove all drawback and issues for the present system.

Mobile ad-hoc network is deployed in applications such as disaster recovery and distributed collaborative computing, where routes are mostly multi-hop and network hosts communicate via packet radios. Mobile ad-hoc network offers a unique art of network formation and can be established in the absence of any fixed infrastructure. Due to the absence of centralized supported structure, an ad-hoc network suffers with various challenges. Some of the known challenges to this area include battery power, routing, bandwidth and security. In this paper we presents the comparative performance analysis for the multicast routing protocol and our proposed methods gives better results than the existing techniques.

Wireless ad-hoc sensor networks have recently emerged as a premier research topic. They have great long-term economic potential, ability to transform our lives and pose many new system-building challenges. Sensor networks pose a number of new conceptual and optimization problems such as location, deployment and tracking in that many applications rely on them for needed information. In this paper we present the comparative performance analysis for the wireless sensor networks using existing and presents techniques for the robustness and reduce the attack in network.

The information over the network in the presence of the third party then it is very necessary to protect our data from the attacker’s, in the series to protect the data we are using the cryptography algorithms. Day to day the new cryptography algorithms are found and there is modification in the previous algorithm also. According to the key the encryption algorithm are of two types. First is symmetric key algorithm and second is asymmetric key algorithms. This is the review work for searching the algorithms which are already derived and discovered, to find the working, advantage and disadvantage of those algorithm. How they algorithm are encrypt and decrypt the data.