## 8 Conclusions  
The present power grid is going through a huge transformation with the deployment of smart grid technology. Smart grid is a complex hierarchical and heterogeneous network. Wireless sensor network is a prominent solution for various applications of smart grid. Wireless sensor networks are distributed collection of sensor nodes situated at various places for measurement and communication of various parameters such as temperature, voltage, current and humidity. These parameters are required for remote monitoring and control of different components of smart grid. WSNs are effective solutions for energy management system in home, industry and business applications. These small sensor nodes are extensively vulnerable to attacks as they are placed in hostile surroundings. Node capture results into complete control of attacker on the WSN node and tampering of hardware as well as software of the node. The energy exhausted sensor nodes can be easily victimized. Therefore, cryptographic security is essential to protect the communication between sensor nodes as well as to detect sensor capture and to invalidate the compromised security keys. The security of dispersed WSN nodes is a crucial technical challenge due to limited memory and computational capabilities of WSN nodes. The data oriented design approach is required for deployment of WSN as the purpose of sensor nodes is to sense and communicate the parameters. Redundant nodes must be deployed to deal with node failures and degraded signal strengths. Traditional communication process involves physical address and IP address of a specific transmitter and receiver to establish a successful communication link. This type of communication is address oriented which is different from WSN approach. As an example, consider the measurement of average temperature of some area. In this case, temperatures from each and every node is not required but an average temperature can be calculated from received readings from sensor nodes positioned at various places. Identity of a specific node is secondary as soon as the readings from all areas are received. The challenges of WSN communication is different from the challenges faced by the usual communication networks. Rigorous and diversified research endeavors in the field of WSN security are inevitable as WSN forms the backbone of smart grid IoT applications. Moreover, various solutions for local and wide area networks are already available due to development of Internet technology. The security of gigantic network of tiny WSN networks is the most challenging aspect of smart grid reliability. In this paper, the analysis of various wireless communication standards, cyber security issues and solutions for WSN are discussed. Nature of various attacks must be known for detection of attacks and development of different solutions at diverse network layers. Apart from well researched solutions such as IDS and cryptographic security, this paper explores topology control for cyber security of wireless sensor networks. Various solutions for intrusion detection and prevention system must be developed for inhibition of adverse effects of cyber-attacks. Secured interoperability between various communication standards is inevitable for robust hierarchical smart grid infrastructure. WSN security is a multi-faceted research topic due to limitations imposed by communication standards and sensor nodes. The cost-security tradeoff must be critically analyzed and implemented for future applications of wireless sensor networks in smart grid applications. The authors declare no conflict of interest. The following abbreviations are used in this manuscript: