ISSD Fall 2010 School of Information, UC Berkeley

"Location" is the most obvious attribute that might be used to make a service "context-aware," but not the only one. Context has been defined as "any information that characterizes a situation related to the interactions between users, applications, and the surrounding environment." The environment consists of places, people, and things, and for each entity there are four categories of context information: location, identity, status (or activity), and time. From the perspective of service design, once again the key principle is that information replaces interaction. There is no need to ask a customer to supply location, time, or other contextual information that the provider has obtained or inferred from another service or sensor. Likewise, there is no value in providing information to the customer that isn’t relevant to his location or context.