What is Location Update Protocol

The mobile computing advent brings a set of new applications that benefit from the constant need of information, diminishing communication costs and favoring the popularization of mobile devices, to reach an increasing number of users. The mobility characteristic opens a new area for software applications. Associated to the mobility we have the location identification, which turns into a critical attribute, once it allows the development of a great variety of new services and applications. The systems that benefit from the use of that location information are named locationbased systems (LBS); alternatively, these applications are also known as location-aware, context-aware, or adaptive information systems More precisely, we can define LBS as applications that use the location information to supply services, based on this position context, to their users (Kupper, 2005; Schiller & Voisard, 2004). The user location information makes available completely new and innovative service concepts, offering information to the user based on its own context (e.g., climatic information in the region where the user is located), increasing considerably the utility of these services. We know that location- based applications increase the services effectiveness, as they give a customized access to the data based on the user’s preferences and on its actual position. This enhances the personalization content, giving several benefits to users and to the application developers. In our daily life, several activities may use these services, like the emergency call centers, the car navigation services, and even location-based friend finder. We may verify that, beyond the already cited characteristics and benefits, what also gave the LBS applications a growing perspective were the location techniques modernization and the mobile devices popularization, enabling the offer of more precise, objective, and useful information. In Shiode et al. (Shiode, Li, Batty, Longley, & Maguire, 2002), research shows the trend of LBS market and the market potential reserved to this class of applications that, each year, turns out to be more important to the users, becoming the area that dominates the applications for mobile devices. According to Sayed (2005), the forecast annual revenues for location-based services was estimated in US $3.3 billions for United States in 2006/2007, and in US $11.7 billions on the other countries. In summary, we may say that the positional information has the potential to explore the user’s geographical context as one of the most important variables for content and services personalization for mobile devices users.