N this information era people are living in a society in which processing, ?ow and Iexchange of information are vital for their existence. Two major issues in such so- ety, which are related to ?ow and exchange of information, are connectivity and mobility. On one hand, computers and Internet provide connectivity and allow communication as well as fast access to large amounts of information. On the other hand, wireless techno- gies bring mobility. People can move and still be able to communicate and have access to various kind of information. Therefore, the functioning of an information...