Underwater sensor networks (UWSNs) are the enabling technology for wide range of applications like monitoring the strong influences and impact of climate regulation, nutrient production, oil retrieval and transportation. Underwater sensor networks mainly differ in the communication media employed for information transmission. The work given reviews the physical fundamentals and engineering implementations for efficient information exchange via wireless communication using physical waves as the carrier among nodes in an underwater sensor network. Wireless Underwater Acoustic Networking is the enabling technology for these applications. Underwater Acoustic Sensor Networks consist of a variable number of sensors and vehicles that are deployed to perform collaborative monitoring tasks over a given area. Underwater sensor networks have been proposed recently to support time-critical aquatic applications such as submarine tracking and harbor monitoring. In Wireless Sensor Networks (WSNs), sensors collaborate to perform various tasks, such as routing. A trust-based routing scheme can be used to route around compromised nodes that attempt to upset this collaboration. In the existing system, the unique characteristics of UASNs make it impossible to directly use these trust models. In the proposed system, the system propose a novel Attack-Resistant Trust model based on Multidimensional trust Metrics (ARTMM) for UASNs. In the ARTMM, multidimensional trust metrics including communication and energy levels are considered.