Paging Scheme Research Articles

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.

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.

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.

MobiCom poster

The IP paging architecture in globally-connected mobile ad-hoc network is presented. Motivated by the energy-efficient design requirement in global-connected mobile ad-hoc network context, we design IP paging support in ad-hoc networks that is independent of, and compatible with, existing IP paging architectures. Two IP paging schemes: proactive paging and reactive paging are proposed. The system is implemented and evaluated with Network Simulator-2. In the reactive scheme, the system suffer less in paging delay and paging overhead. On the other hand, it is more energy-efficient in proactive scheme.

Some observations on using meta-heuristics for efficient location management in mobile computing networks

With the increase in global wireless communication, there is a need for efficient network management strategies. Location management in a mobile network involves keeping track of mobile host (MH) cell locations. MHs perform location updates to inform the network of their location. When a call arrives for an MH, the network uses its last known cell location and a paging strategy to find that host. Current location management techniques do not consider host-mobility patterns or call arrival rates. This paper describes a selective update strategy that is modeled on the characteristics of a network, such as, topology, host mobility patterns and connection request rates. Then, a genetic algorithm is used to solve the location management problem that involves the search of a large solution space. The aim of the work is to determine whether genetic algorithms can be applied successfully to solve this problem, and to evaluate their efficiency in solving this class of optimization problems. Results from the selective update strategy show improvements over alternative algorithms. The location management optimization problem is shown to be well adapted to the workings of the genetic algorithm. The proposed solution also saves power, processing time, and network bandwidth.

Two-stage ensemble paging strategy for cellular communication systems

Instead of per user basis, we propose a simple paging strategy based on the consideration of ensemble paging channel resource of each cell. Using only the information of the last known locations of mobile subscribers, the proposed paging scheme under a maximum delay constraint can improve the system performance (discovery rate, blocking rate, and average paging delay) significantly in the heavy load.

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.

User mobility pattern scheme for location update and paging in wireless systems

The user mobility pattern (UMP) scheme is introduced for location update and paging in wireless systems where mobile terminals (MTs) maintain their history data in a database called user mobility history (UMH). During a location update, a UMP is derived from UMH and registered to the network. Unless the MT detects that it has moved out of the registered UMP, it does not perform any other location update. On the other hand, cells are paged selectively according to the cell entry times in the registered UMP upon a call arrival for the MT. The related data structures and the protocols for the UMP scheme are presented in the paper. The experimental results show that the UMP scheme outperforms the time-based and movement-based location update schemes as well as the blanket, selective, and velocity paging schemes.

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.

IDMP-based fast handoffs and paging in IP-based 4G mobile networks

We consider the use of our previously proposed Intra-Domain Mobility Management Protocol (IDMP) in fourth-generation mobile networks. On evaluating the heterogeneous access technologies, cellular layouts, and application characteristics of 4G environments, we realize a need to reduce both handoff latency and the frequency of mobility-related signaling. We first present IDMP's fast intradomain handoff mechanism that uses a duration-limited proactive packet multicasting solution. We quantify the expected buffering requirements of our proposed multicasting scheme for typical 4G network characteristics and compare it with alternative IP-based fast handoff solutions. We also present a paging scheme under IDMP that replicates the current cellular paging structure. Our paging mechanism supports generic paging strategies and can significantly reduce the mobility-related IP signaling load.

Modeling Mobility Tracking Procedures in PCS Systems Using Stochastic Activity Networks

In this paper the capability of stochastic activity networks (SANs) has been used as a novel approach in the analysis of mobility tracking procedures. To evaluate complex systems such as cellular systems, powerful tools for modeling and analysis are required. SANs have proved to be very flexible and powerful tools in the study of location update (LU) and paging (PG) schemes. SANs can capture, in a simple manner and from the mobility models under study, much more detail than Markov models. Therefore, the analysis of mobility tracking procedures with SANs provides more accuracy than the use of Markov models. This fact is illustrated in the paper by considering the LU and PG schemes proposed in Ref. [12]. Furthermore, our results show a much better performance of these schemes than that predicted by Ref. [12].

Caching and Scheduling for Broadcast Disk Systems

Unicast connections lead to performance and scalability problems when a large client population attempts to access the same data. Broadcast push and broadcast disk technology address the problem by broadcasting data items from a server to a large number of clients. Broadcast disk performance depends mainly on caching strategies at the client site and on how the broadcast is scheduled at the server site. An on-line broadcast disk paging strategy makes caching decisions without knowing future page requests or access probabilities. This paper gives new implementations of existing on-line algorithms and reports on extensive empirical investigations. The gray algorithm [Khanna and Liberatore 2000] always outperformed other on-line strategies on both synthetic and Web traces. Moreover, caching limited the skewness of broadcast schedules, and led to favor efficient caching algorithms over refined scheduling strategies when the cache was large.

Paging area planning in future cellular systems

AbstractEfficient resource utilisation in future cellular systems is related to the control of the signalling load imposed by the paging operations. This relies on the application of efficient paging schemes, and on the “proper” planning of paging areas. In this paper we define and solve a version of the paging area planning problem. In particular, we provide a low complexity algorithm, under the assumption that the scheme applied falls within the last interaction based paging (LIBP) category.

Extending mobile IP with adaptive individual paging

This paper proposes to extend Mobile IP with adaptive individual paging. Paging reduces the signaling cost of Mobile IP making it more adapted to wireless cellular IP networks. By reducing the number of location updates to be sent per mobile host, paging also minimizes power consumption of the mobile devices. In the proposed extension, each mobile host computes dynamically its optimal location area size according to its traffic and mobility parameters. The optimal size is the size that provides the best paging versus location update cost tradeoff and, as a result, minimizes the signaling load in the network. We compare, by simulation, the performance of the proposed scheme with that of Mobile IP [11], a paging scheme that uses fixed size location areas and Hierarchical Mobile IP [5]. We show that our extension provides a significant gain compared to Mobile IP and the fixed size paging scheme and performs as well and sometimes better than Hierarchical Mobile IP. We also show that the integration of adaptive individual paging within Hierarchical Mobile IP outperforms all schemes.

Effective paging schemes with delay bounds as QoS constraints in wireless systems

In this paper new paging schemes are presented for locating mobile users in wireless networks. Paging costs and delay bounds are considered since paging costs are associated with bandwidth utilization and delay bounds influence call setup time. In general, location tracking schemes require intensive computation to search for a mobile terminal in current PCS networks. To reduce the paging costs, three new paging schemes, reverse, semi-reverse and uniform, are introduced to provide a simple way of partitioning the service areas and decrease the paging costs based on each mobile terminal's location probability distribution. Numerical results demonstrate that our approaches significantly reduce the paging costs for various probability distributions such as uniform, truncated discrete Gaussian, and irregular distributions.

An optimal paging scheme for minimizing signaling costs under delay bounds

This letter introduces a method for minimizing paging costs in wireless systems with delay constraints. An optimal partition algorithm is proposed and the corresponding paging procedure is provided. Numerical results demonstrate that the new scheme outperforms other previous schemes for uniform and nonuniform location probability distributions.

A contention-free mobility management scheme based on probabilistic paging

In forthcoming personal communication systems (PCSs), small cells are deployed to achieve high spectral efficiency. This has significant impacts on location tracking of mobile users. The increase in location update (LU) load leads to more contention on the reverse control channel. Thus, many algorithms are designed to distribute the LU load to a larger number of cells. This avoids the inefficiency of random accessing due to high offered load. In an alternative approach (Wong 1995), a contention-free LU algorithm is proposed. Two or more mobile units are permitted to register with a base station simultaneously without contention. A probabilistic paging mechanism called Bloom filtering is used to select cells to be paged. Since there is no contention in LU, inefficiencies due to random accessing are bypassed. In this paper, we present another contention-free LU algorithm. It is hybrid in the sense that LUs are temporally or geographically triggered. The use of hybrid LU alleviates inefficiencies inherent to temporal triggered LU in Wong. Three selective paging schemes are considered in this paper. Tradeoff between paging delay and paging bandwidth is addressed. The performance of this algorithm is compared to Wong and other conventional strategies. Numerical results show that the new algorithm compares favorably with previous proposed strategies.

On-Line Paging Against Adversarially Biased Random Inputs

In evaluating an algorithm, worst-case analysis can be overly pessimistic. Average-case analysis can be overly optimistic. An intermediate approach shows that an algorithm does well on a broad class of input distributions. E. Koutsoupias and C. H. Papadimitriou (1994, in “Proc. of the 35th IEEE Annual Symp. on Foundation of Computer Science,” pp. 394–400, IEEE Press, New York) recently analyzed the least-recently-used (LRU) paging strategy in this manner, analyzing its performance on an input sequence generated by a so-called diffuse adversary—one that must choose each request probabilistically so that no page is chosen with probability more than some fixed ϵ>0. They showed that LRU achieves the optimal competitive ratio (for deterministic on-line algorithms), but they did not determine the actual ratio. In this paper we estimate the optimal ratios within roughly a factor of two for both deterministic strategies and randomized strategies. Around the threshold ϵ≈1/k (where k is the cache size), the optimal ratios are both Θ(lnk). Below the threshold the ratios tend rapidly to O(1). Above the threshold the ratio is unchanged for randomized strategies but tends rapidly to Θ(k) for deterministic ones. We also show that the competitive ratios for First-in-first-out (FIFO) and Flush-when-full (FWF) are both k when ϵ≥1/k. In contrast, the ratio for LRU is less than 2lnk+4 when ϵ=1/k. It is folklore that LRU outperforms FIFO in practice, but to date the only other variant of competitive analysis in which LRU has been shown to outperform FIFO is the access graph model. For completeness, we give an alternate proof of the optimality of LRU.