Advances in hardware technology and wireless communication have enabled the deployment of largescale sensor networks, where thousands to millions of self-powered, small and low-cost sensor nodes are distributed over a vast field to obtain sensing data. These sensor nodes are equipped with sensing, communicating, and data processing units, which allow sensor nodes to collect, exchange, and process data of the environment. The processing units used in the current generation of sensor nodes are already powerful enough to perform some complicated algorithms to process sensing data, and they are expected to be more powerful in the future. Due to these attractive characteristics, wireless sensor networks are ideal candidates for a wide range of civil applications and military operations. This paper provides an indepth study of applying wireless sensor networks to real-world mad-cow disease monitoring and beef distribution safety system. An extensive survey of the state of the art to design a distributed system for pervasive computing is conducted. A set of techniques and mechanisms are compared and ranked in the paper. Then the characteristics for designing this kind of pervasive system are listed; the system architecture is presented; and an instance of the key mechanisms for monitoring the mad-cow disease and tracking beef distribution system is presented. This system supports real-time communication and multitasking scheduling as well.