Historical based location management strategies for PCS networks

Abstract

Due to the current popularity of wireless communication, personal communication service networks have attracted a lot of attention. As mobile terminals (MTs) in such networks have the ability to communicate on the move, location management (LM) is a critical issue that should be handled carefully. Managing MTs locations is to simultaneously perform two main operations, which are; location update and paging. A good LM strategy maintains both operations with the minimum time and signaling penalties. Although several LM strategies have been introduced, they still suffer from several drawbacks. This paper introduces three novel LM strategies, which are; historical based location management (HBLM), direction based location management (DBLM) and trajectory based location management (TBLM). TBLM strategy is based on geographical position of MTs, while HBLM and DBLM are based on geographical position of MTs as well as time aspects. Visited locations are saved in MT's internal cache in the form of cell identifier as well as the corresponding time interval. Location tracking is fully supervised by the MT's current visitor location register (VLR). On the other hand, the collected location information in MT's cache is sent to VLR when MT passed through a previously defined number of cells or when a previously defined number of time periods has elapsed. In HBLM, paging is done according to the historical movements saved in VLR, while DBLM takes also MT's movement direction into consideration while in TBLM, paging is done according to the historical trajectories that MTs are used to follow. Experimental results have shown that the proposed LM strategies significantly improve MTs' tracking process as they introduce the minimum signaling penalty (for paging and registration) with an acceptable paging time delay compared with recent LM strategies.

Modeling privacy approaches for location based services

“…The queue length for a arrival per second is a little more than 1, where as for 7 arrivals per second the queue length is about 2.5. This is because queue length is directly proportional to λ, as given in Equation 15. On the other hand, we find that the sojourn time decreases with arrival as shown in Figure 6.…”

“…The LBS privacy schemes that we have seen so far assume that the adversary can acquire a single request, the so called snapshot case. Historical attacks [14,15,16,17] assume that the adversary is able to link a set of requests fired by a user. One solution to this problem is the application of Hilbert Cloaking algorithm [16,17] which basically exploit the Hilbert space filling curve to find a total order among the user's various locations.…”

“…The algorithm then returns the minimum bounding rectangle (MBR), considering the position of other users that are in the same MBR as the actual user. To improve the spatial accuracy, heuristics have been proposed [14,15] that recursively tries to shrink the obtained MBR. From a queueing theory point of view, these algorithms are similar to the top-down approach and thus can be modeled using a M/M/1 queueing model.…”

Optimal management of distance-based location registration using embedded Markov chain

“…Generally, the best trade-off exists between the registration and paging costs, which lead to optimal usage of the radio resources. [4][5][6] The numerous LR schemes have been proposed so far: zone-based, 4,5 movement-based, [7][8][9][10][11] timerbased, 8,11,12 distance-based, [13][14][15][16] and tracking area list (TAL)-based [17][18][19] registrations. In zone-based registration, UE registers a new location area on the network whenever it moves to a new zone.…”

Modeling and cost analysis of zone-based registration in mobile cellular networks

“…Many studies have been published on various location registration schemes, and there have been studies on distancebased registration [3,4], movement-based registration [3,[5][6][7], time-based registration, and so on [8,9]. However, most studies on mobility management have considered or included zone-based registration (ZBR) [10][11][12][13][14][15][16] because it is widely adopted by most mobile cellular networks.…”