Wireless sensor networks can be used to measure and monitor many challenging problems and typically involve in monitoring, tracking and controlling areas such as battlefield monitoring, object tracking, habitat monitoring and home sentry systems. However, wireless sensor networks pose unique security challenges including forgery of sensor data, eavesdropping, denial of service attacks, and the physical compromise of sensor nodes. Node in a sensor networks may be vanished due to power exhaustion or malicious attacks. To expand the life span of the sensor network, a new node deployment is needed. In military scenarios, intruder may directly organize malicious nodes or manipulate existing nodes to set up malicious new nodes through many kinds of attacks. To avoid malicious nodes from joining the sensor network, a security is required in the design of sensor network protocols. In this paper, we proposed a security framework to provide a complete security solution against the known attacks in wireless sensor networks. Our framework accomplishes node authentication for new nodes with recognition of a malicious node. When deployed as a framework, a high degree of security is reachable compared with the conventional sensor network security solutions. A proposed framework can protect against most of the notorious attacks in sensor networks, and attain better computation and communication performance. This is different from conventional authentication methods based on the node identity. It includes identity of nodes and the node security time stamp into the authentication procedure. Hence security protocols not only see the identity of each node but also distinguish between new nodes and old nodes.
Now a day’s sensors can monitor pressure, temperature, humidity, soil makeup, noise levels, vehicular movement, and lighting conditions, the presence or absence of certain kinds of objects or substances, mechanical stress levels on attached objects, and other properties. In case of wireless sensor network, the communication among the sensors is done using wireless transceivers. Basically the major challenge for employing any efficient security scheme in wireless sensor networks is created by the size of sensors, as a result the memory, processing power and type of tasks affected from the sensors. To deal with the important security issues in wireless sensor networks we talk about cryptography, steganography and other basics of network security and their applicability. We investigate various types of threats and attacks against wireless sensor network to save manufacturing cost. A sensor node is usually built as a small device, which has limited memory, a low-end processor, and is powered by a battery. So during the design of any security solution we need to take care of resource constraints like limited energy, limited memory, limited computing power, limited communication bandwidth, limited communication range.