Context Repository Architecture for Smart Collaborative Environment

Due to the advancement of technology, smart sensors and smart objects are becoming popular now-a-days. These smart sensors and objects have some computation power so that depending on the change of the environment they can take actions accordingly. Since the use of portable devices like PDA, cellular phone is increasing; users also would like to interact with the environment through these. Moreover, for performing complex operations, the authors need to have context middleware that can analyze the contexts and provide necessary services to users. Therefore, it is obvious that for all of these cases, a repository of contexts is badly needed to store the generated contexts as well as to retrieve those contexts whenever necessary.