A Survey on the Location Management Problem in Mobile Networks

The question ”Where is X?” is one of the commonly asked questions in our daily life. In mobile networks, this is connected with a fundamental location management problem, whose goal is to maintain a centralized/distributed database which maps X to its current location. X could be a person, a mobile host, an IP address, or a telephone number. X’s location is a conceptual term which may be reflected by a physical or relative location, a logical area, a subnet, or a cell ID. In this article, we review this essential issue in three major types of network architectures: cellular networks, IP networks, and mobile adhoc networks. Although each particular network has its own concerns, the problem can be analyzed from two aspects: update and page. Finally, We summarize the article by introducing recent location management standardization reports and suggesting a cross-domain framework for different networks to share location information.