Paging Cost Research Articles

Design and analysis of location management for 3g cellular networks

Location management is a key issue in personal communication service networks to guarantee the mobile terminals to continuously receive services when moving from one place to another. We study two location management schemes, a dynamic movement-based scheme (DYNAMIC-3G) and a static scheme (STATIC-3G), for 3G cellular networks where home location registers, gateway location registers (GLRs), and visitor location registers form a three-level hierarchical mobility database structure. For both schemes, the cost functions are formulated analytically. We prove that there is an optimal movement threshold that minimizes the total cost function of DYNAMIC-3G and propose a binary search algorithm to find the optimal threshold. Furthermore, we present performance evaluation and comparison of the proposed schemes with the previous schemes in 2G cellular networks where the GLR is not present. Our studies validate the optimality of the DYNAMIC-3G scheme and show that the proposed schemes outperform the previous schemes, especially when the remote-local-cost ratio is high. The comparison results between DYNAMIC-3G and STATIC-3G indicate that DYNAMIC-3G should be adopted when the mobility rate is low, and STATIC-3G should be adopted otherwise. Furthermore, DYNAMIC-3G tends to perform better than STATIC-3G when the paging cost is high or the number of cells in a location area is large.

Optimal Sequential Paging in Cellular Wireless Networks

In a high-capacity cellular network with limited spectral resources, it is desirable to minimize the radio bandwidth costs associated with paging when locating mobile users. Sequential paging, in which cells in the coverage area are partitioned into groups and paged in a non-increasing order of user location probabilities, permits a reduction in the average radio costs of paging at the expense of greater delay in locating the users. We present a polynomial time algorithm for minimizing paging cost under the average delay constraint, a problem that has previously been considered intractable. We show the conditions under which cluster paging, a simple heuristic technique proposed for use with dynamic location update schemes, is optimal. We also present analytical results on the average delay and paging cost obtained with sequential paging, including tight bounds.

Concurrent Search of Mobile Users in Cellular Networks

In this paper, we propose to concurrently search for a number of mobile users in a wireless cellular network based on the probabilistic information about the locations of mobile users. The concurrent search approach guarantees that all k mobile users will be located within k time slots. It is shown that even in the worst case when mobile users appear equally in all the cells of the network, the concurrent search approach is able to reduce the average paging cost by 25%. More importantly, this is achieved without an increase in the worst case paging delay or in the worst case paging cost. Depending on the total number of mobile users to be located, total number of cells in the network, and the probabilistic information about the locations of mobile users, the reduction of the average paging cost due to the usage of the concurrent search approach ranges from 25% to 88%. The case in which perfect probabilistic information is unavailable is also studied.

A Novel Sectional Paging Strategy for Location Tracking in Cellular Networks

In this letter, we propose a new paging technique, sectional paging, that reduces the paging cost while complying with the delay constraint for mobiles roaming with traceable patterns. Without having to install much additional complexity, the developed scheme predicts the likelihood of residence and assigns optimal paging boundaries. Thus while complying with the required delay constraints, quality-of-service (QoS) measures will not need to be sacrificed as a result of increasing the update threshold. Under the same network conditions and mobile characteristics, simulation results reveal that the usage of sectional paging is most suitable when the roaming pattern is either traceable or can be predicted with reasonable precision.

Probability criterion paging area planning in future mobile communications systems

Future mobile telecommunications systems are obligated to offer advanced multimedia services to a huge number of users. The burden imposed by the signaling operations supporting these services can severely degrade the system performance and lead to congestion problems in network equipment (switches, databases, gateways, etc.). Paging operations in a mobile cellular network are responsible for a large part of the signaling load and, therefore, the issue of how to efficiently conduct them becomes of critical importance. The key to its solution lies on the application of multiple step paging schemes and on the ‘proper’ planning of paging areas (PAs). In this paper, we devise and solve a version of the PA-planning problem. In particular, we provide a low complexity probabilistic algorithm capable of reducing paging costs. To improve performance, the algorithm uses additional information regarding the locations of last user-network interactions. Numerical results show that significant savings can be achieved compared to a conventional paging scheme.

A learning strategy for paging in mobile environments

AbstractThe essence of designing a good paging strategy is to incorporate the user mobility characteristics in a predictive mechanism that reduces the average paging cost with as little computational effort as possible. In this scope, we introduce a novel paging scheme based on the concept of reinforcement learning. Learning endows the paging mechanism with the predictive power necessary to determine a mobile terminal's position, without having to extract a location probability distribution for each specific user. The proposed algorithm is compared against a heuristic randomized learning strategy akin to reinforcement learning, that we invented for this purpose, and performs better than the case where no learning is used at all. It is shown that if the user normally moves only among a fraction of cells in the location area, significant savings can be achieved over the randomized strategy, without excessive time to train the network. Copyright © 2003 John Wiley & Sons, Ltd.

Performance evaluation of location management in umts

The universal mobile telecommunications system utilizes a three-level location-management strategy to reduce the net costs of location update and paging in the packet-switched service domain. Within a communication session, a mobile station (MS) is tracked at the cell level during packet transmission. In the idle period of an ongoing session, the MS is tracked at the UTRAN registration area (URA) level to avoid frequent cell updates while still keeping the radio connection. If the MS is not in any communication session, the MS is tracked at the routing-area (RA) level. The inactivity counter mechanism was proposed in 3GPP 25.331 to determine when to switch between the three location-tracking modes. In this mechanism, two inactivity counters are used to count the numbers of cell and URA updates in an idle period between two packet transmissions. If the number of cell updates reaches a threshold K/sub 1/, the MS is switched from cell tracking to URA tracking. After that, if the number of URA updates reaches a threshold K/sub 2/, the MS is tracked at the RA level. The paper proposes analytical and simulation models to investigate the performance of the inactivity counter mechanism. Our study provides guidelines for K/sub 1/ and K/sub 2/ selection to achieve lower net costs of location update and paging.

A mobility management strategy for gprs

In general packet radio service (GPRS), a mobile station (MS) is tracked at the cell level during packet transmission, and is tracked at the routing-area (RA) level when no packet is delivered. A READY timer (RT) mechanism was proposed in 3GPP 23.060 to determine when to switch from cell tracking to RA tracking. In this mechanism, a threshold interval T is defined. If no packet is delivered within T, the MS is tracked at the RA level. When a packet arrives, the MS is tracked at the cell level again. However, the RT mechanism has a major fallacy in that the RTs in both the MS and the serving GPRS support node may lose synchronization. This paper considers another mechanism called READY counter (RC) to resolve this problem. In this approach, a threshold K is used. Like the RT approach, the MS is tracked at the cell level during packet transmission. If no packets are delivered after the MS has made K cell crossings, the MS is tracked at the RA level. We also devise an adaptive algorithm called dynamic RC (DRC). This algorithm dynamically adjusts the K value to reduce the location update and paging costs. We propose analytic and simulation models to investigate RC, RT, and DRC. Our study indicates that RC may outperform RT. We also show that DRC nicely captures the traffic-mobility patterns and always adjusts the K threshold close to the optimal values.

A parallel shuffled paging strategy under delay bounds in wireless systems

In sequential paging schemes, the paging process is considered on per user basis. When an incoming call arrives to a mobile terminal (MT), the associated location area is divided into several paging areas (PAs) and PAs are paged one by one until the MT is found. Even though sequential paging algorithms can reduce the paging cost compared to the blanket-paging scheme, they introduce extra and unnecessary delay due to the fact that, during each paging cycle, unpaged cells are idle and unused in terms of paging. In this letter, a simple parallel shuffled paging strategy is proposed to reduce delay and improve performance. In the proposed scheme, multiple MTs can be paged in difference PAs in parallel. Our study shows that the proposed scheme outperforms both the sequential paging and the blanket paging in terms of discovery rate and queueing delay.

Concurrently searching for mobile users in cellular networks

In today's systems, upon arrival of calls to mobile users, the system attempts to locate the users sequentially (one by one) through a paging operation. In this letter, we propose to concurrently search for a number of mobile users in a mobile network, significantly reducing the cost of locating mobile users. The reduction in the paging costs due to such a concurrent search can be quite substantial, depending on the knowledge of the probabilities of the users' locations, the number of cells in the network, and the number of mobiles to be located. Additionally, we propose a low-complexity heuristic that reduces the average paging cost by 25%, in the case of no knowledge of probabilities of the mobiles' locations. With such knowledge, further reduction in the average paging costs of up to 90% can be achieved.

Optimal fractional movement-based scheme for PCS location management

In this letter, we propose a fractional movement-based location update scheme for personal communication service networks. Similar to the well-known fractional guard channel scheme for channel assignments, in our proposed scheme, the movement threshold is a real number with a fraction instead of an integer. We prove analytically that there is a unique optimal fractional movement threshold that minimizes the total cost of location updates and paging per call arrival.

An Efficient Paging Strategy Based on Paging Agents of Base Stations in Cellular Mobile Networks

We propose a new paging strategy to reduce paging cost by adding paging agents at base stations. When a mobile-terminated call occurs, the base stations look up the paging agents to determine if terminal paging is actually to be made. An analytical model based on a Markov chain is used to evaluate the performance of the proposed strategy. The numerical results show that the proposed strategy significantly reduces the paging cost compared with the simultaneous paging strategy.

Scitex Digital Printing and Production Digital Technology

Scitex Digital Printing (SDP), Inc. manufactures high speed digital printers. Recent advancements in technology from SDP have defined a new category of print, Business Color™.Markets and applications of Business Color include Direct Mail, Transactional Documents and Book Printing. Each of these applications have unique opportunities for Business Color printing including high variability of data, elimination of pre-print, and fast job changeover.SDP products such as the Business Color Press with VersaMark® printheads are designed to provide low per page costs at high print volumes of 100% variable documents. SDP has developed modular Business Color printing systems to allow printing businesses to start with monochrome printing and transition their print offerings to include spot and process color. Product modularity also allows press capacity and versatility to increase with increased demand.VersaMark printheads use continuous inkjet technology to print water based inks at 300 x 300 or 300 x 600 dpi. Printheads are 9” wide and can print up to 500 fpm. Paper treatment and coating technologies contribute to improving print quality; a variety of software technologies enable customers to produce documents with Business Color technology.

Hierarchical Group Location Tracking for Transportation Systems inWireless Personal Communication Networks

A hierarchical group location tracking (HGLT) based on group location tracking and hierarchical location update is proposed to reduce the location management cost for terrestrial transportation systems (TSs) in personal communication networks. A global group location update (GGLU) and a local group location update (LGLU) are performed to provide an accurate position for a user. The GGLU informs a virtual visitor location register of the currently camped-on location area and the LGLU informs the serving mobile switching center of the currently camped-on cell. Although the LGLU is done each time a TS moves into a new cell, it causes small increment in the signaling cost due to localized updates and group updates compared with the previous group location tracking scheme. The proposed scheme significantly reduces the paging cost because the scheme pages only a camped-on cell using the LGLU information. Compared with the previous schemes, the HGLT reduces the location management cost, and it is more efficient as the cost for paging a cell increases.

An intra-LA location update strategy for reducing paging cost

The blanket paging strategy in current mobile networks may waste a lot of wireless bandwidth. While keeping the standard location area (LA) based location update (LU) strategy unchanged, we propose an intra-LA LU scheme to reduce the paging cost. While a mobile terminal (MT) is residing in an LA with a cell called anchor cell, where the MT usually stays for a significant period, an intra-LA LU is performed whenever the MT changes its location between the anchor cell and the rest of cells in the LA. For an incoming call, either the anchor cell or the rest of cells in the LA is paged to locate the MT. Thus the paging cost is greatly reduced, especially when the called MT is located in its anchor cell.

Some Changes in Annals

Editorials2 July 2002Some Changes in AnnalsHarold C. Sox, MD, EditorHarold C. Sox, MD, EditorSearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-137-1-200207020-00015 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail The beginning of a new volume of Annals is the occasion to tell readers about the changes that we made during the past 6 months. All of these changes ultimately benefit our readers, if only by making Annals a more attractive place for authors to publish their best work.Most of these changes will enable us to publish more material without increasing the number of pages in the print version of Annals. We are limited in the number of pages we publish because each page costs about $25 000 per year, a charge that members of the American College of ... Author, Article, and Disclosure InformationAffiliations: PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics 2 July 2002Volume 137, Issue 1Page: 55KeywordsBreast cancerChemopreventionElectrode recordingLibrariesMovement disordersSoftware tools ePublished: 2 July 2002 Issue Published: 2 July 2002 Copyright & PermissionsCopyright © 2002 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

A new analytic framework for dynamic mobility management of PCS networks

This paper presents a new analytic framework for dynamic location management of PCS networks. Based on the theory of hexagonal cellular patterns, a novel two-dimensional Markov walk model with six states is proposed to characterize the dynamic behavior of the intercell movements for a mobile station. We discover a broad class of isotropic processes having an identical uniform steady-state distribution of the six directions, but distinct circulant transition probability matrices. Six special isotropic processes exhibiting IID, directional, turning, ping-pong, h-spin, and t-spin mobility patterns are identified for performance comparison. We also generalize the selective paging strategy by introducing the concept of probabilistic selective paging (PSP) to reduce the paging cost. A unified analysis using recursive computations is carried out to compute the exact probability distribution for the number of per-call location updates. We calculate the location profile with respect to an incoming call and derive an exact expression of the average paging cost for PSP. With its ability to distinguish subtle performance variations and unveil new features of various dynamic location management schemes, our analytic framework is demonstrated to provide more precise and insightful results than conventional analysis.

Reducing location update and paging costs in a PCS network

Mobility tracking operations in a personal communication service (PCS) system are signaling consuming. Several strategies have been proposed in the literature to reduce both the location update (LU) and the paging (PG) costs. In this paper, we propose a location-tracking algorithm called three-location area (TrLA), combined with selective paging. In TrLA, the mobile terminal (MT) allocates the identification of three neighboring location areas (LAs) in its local memory. We call this set of three LAs, a big-location area (BLA). Each time the MT exits the BLA, it triggers an LU message to the system databases via a base station, in order to maintain the databases up to date. The MT also updates its cache memory. A two-step selective PG is also considered and compared with the single-step (or nonselective PG). An analytical model based on a semi-Markov process has been used to evaluate our proposal. This scheme is compared with the classical Global System for Mobile Communications (GSM) standard and the two-location algorithm proposal. As a result, this new scheme outperforms the cited strategies, and in our opinion, it can easily be implemented in existing standard cellular and personal communication systems.

Hierarchical group location tracking for transportation systems in PCS networks

A hierarchical group location tracking (HGLT) is proposed to reduce the location management cost for transportation systems in personal communication services networks. The HGLT performs global group location updates and local group location updates (LGLUs) to obtain an accurate user location. Small increment in the signalling cost due to the LGLUs results in significant reduction in paging cost. The HGLT is an appropriate solution in high paging cost systems.

LeZi-update: an information-theoretic framework for personal mobility tracking in PCS networks

The complexity of the mobility tracking problem in a cellular environment has been characterized under an information-theoretic framework. Shannon's entropy measure is identified as a basis for comparing user mobility models. By building and maintaining a dictionary of individual user's path updates (as opposed to the widely used location updates), the proposed adaptive on-line algorithm can learn subscribers' profiles. This technique evolves out of the concepts of lossless compression. The compressibility of the variable-to-fixed length encoding of the acclaimed Lempel---Ziv family of algorithms reduces the update cost, whereas their built-in predictive power can be effectively used to reduce paging cost.