Location Management for Networks with Mobile Users

Location management is one of the the most fundamental problems facing mobile networking today. How does the network know where the intended recipient of a message is currently located? Where should the information about the current location of a user be stored? Who should be responsible for determining user’s location? These are examples of questions which location management attempts to address. Different location management schemes for networks such as Internet and analog voice networks such as cellular have been proposed. Unfortunately, the picture that has emerged so far is very confusing with several overlapping terms introduced that contribute to a ballooning terminology. It does not help of course that the problem is being actively addressed by two large and distinct communities: the Internet community and the cellular/PCN community with each group favoring its own terminology. The objective of this paper is to offer a general and hopefully a simplifying view of location management. We will try to explain a number of different approaches to location management using a small set of simple terms. We will show differences and similarities between different methods and generally discuss the most important performance parameters. We will also discuss future research directions.