Associative IP paging based on hierarchical mobile IPv6

IP paging is a well‐known topic, which focuses on reducing amount of binding update (BU). Various IP paging architectures rely on multicast/broadcast to send their messages in wireless network. However, multicast/broadcast is unreliable and has limited bandwidth in power saving mode. This paper uses unicast to avoid exhaustion of the limited bandwidth and reliably page mobile nodes (MNs) by layer 2's supporting acknowledgment in nature. Furthermore, we successfully suppress the amount of BU by remembering and checking MNs' ever attached on‐link care of addresses (LCoAs) in the stack, which is maintained by least recently used (LRU) algorithm for efficiently paging while MNs moving in a localized pattern. We simulate this mechanism to obtain the optimal stack size, which can dramatically reduce the signals of location update and paging. Copyright © 2009 John Wiley & Sons, Ltd.     

Hash-Based Paging and Location Update Using Bloom Filters

We develop and analyze a hash-based paging and location update technique that reduces the paging cost in cellular systems. By applying a Bloom filter, the terminal identifier field of a paging message is coded to page a number of terminals concurrently. A small number of terminals may wake up and send what we call false location updates although they are not being paged. We compare the total number of paging and false location update messages with the cost of the standard paging procedure. Fortunately, the false location update probabilities can be made very small, and important bandwidth gains can be expected. The larger the size of the terminal identifier, the less probable are false location updates. Therefore, hash-based paging especially shows promise for IP paging in mobile IPv6 networks with 128-bit mobile host addresses.     

A mobile host protocol supporting route optimization andauthentication

Host mobility is becoming an important issue due to the recent proliferation of notebook and palmtop computers, the development of wireless network interfaces, and the growth in global internetworking. This paper describes the design and implementation of a mobile host protocol, called the Internet mobile host protocol (IMHP), that is compatible with the TCP/IP protocol suite, and allows a mobile host to move around the Internet without changing its identity, In particular, IMHP provides host mobility over both the local and wide area, while remaining transparent to the user and to other hosts communicating with the mobile host. IMHP features route optimization and integrated authentication of all management packets. Route optimization allows a node to cache the location of a mobile host and to send future packets directly to that mobile host. By authenticating all management packets, IMHP guards against possible attacks on packet routing to mobile hosts, including the interception or redirection of arbitrary packets within the network. A simple new authentication mechanism is introduced that preserves the level of security found in the Internet today, while accommodating the transition to stronger authentication based on public key cryptography or shared keys that may either be manually administered or provided by a future Internet key management protocol     

P-MIP: Paging Extensions for Mobile IP

As the number of Mobile IP users grows, so will the signalling overhead associated with Internet mobility management in the core IP network. This presents a significant challenge to Mobile IP as the number of mobile devices scale-up. In cellular networks, registration and paging techniques are used to minimize the signalling overhead and optimize the mobility management performance. Currently, Mobile IP supports registration but not paging. In this paper, we argue that Mobile IP should be extended to support paging to improve the scalability of the protocol to handle large populations of mobile devices. To address this, we introduce P-MIP, a set of simple paging extensions for Mobile IP, and discuss the construction of paging areas, movement detection, registration, paging and data handling. We present analysis and simulation results for Mobile IP with and without paging extensions, and show that P-MIP can scale well supporting large numbers of mobile devices with reduced signalling under a wide variety of system conditions.     

Reducing Hard Handover Overhead in Future All-IP Wireless Access Networks

In host-based routing (HBR) domains such as cellular IP, handover can be executed implicitly via path update packets from the new location of the mobile host (MH). The direction of the flow of packets destined to the MH is diverted at the crossover node (CoN), thereby reducing to a minimum the handover delay and associated packet loss. As the depth of the network increases so does the path update time to the CoN. To reduce the handover overhead, an architectural extension is proposed to the path update process, by adding a multi-homed base-station (MHOBS) at certain points in the wireless access network where the path update delay becomes severe. Two scenarios are investigated. The first scenario is one in which the old and new paths to the MH are equal in length or symmetrical, the second, when the paths are unequal, or asymmetrical.     

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.     

Analysis of a mobility management scheme considering battery power conservation in IP-based mobile networks

Mobile hosts (MHs) in all IP-based mobile networks must update their current location to receive incoming packets. The MHs are idle for most of time. Both registration of approximate location information and paging can facilitate efficient power management for the idle MHs. Furthermore, the MHs can be in switch-off state for battery power conservation. Mobile IP, the current standard for IP-based mobility management, needs to be enhanced for use in all IP-based mobile networks. Mobility management in all IP-based mobile networks should consider idle and detached MH states as well as active MH state. A mobility management scheme for all IP-based mobile networks is introduced in this paper. This scheme includes management of communicating, attentive, idle, and detached states. We model MH behavior in the networks when the binding-lifetime-based registrations are utilized as a means of identifying that an MH is switched off. The steady-state probabilities for MH state transitions are derived, and an optimal rate of binding-lifetime-based registrations that results in minimum network cost is derived.     

Traffic load metrics for multihomed mobile IP and global connectivity

Support for host mobility an essential and necessary feature for roaming users who connect to wireless networks via access points. Access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will discover multiple access points in this environment. In such an environment, a mobile host should be able to use the best available connection to communicate with a correspondent host and perhaps use multiple connections for different hosts. In areas with wireless local area network access, pockets with limited or no coverage could exist. Such restricted connectivity could be compensated by neighbor hosts who form an ad hoc network and relay packets until they reach an access point. This paper describes and discusses a proposed solution towards enabling and supporting connectivity in wireless networks. In the proposed solution the network layer software will evaluate and decide which wireless network connections to use. A Running Variance Metric (RVM) and a Relative Network Load(RNL) are used to measure the traffic load of access points in wireless access networks. RVM and RNL can be efficiently used for both infrastructure networks and ad hoc networks. Multihomed Mobile IP (M-MIP) is an extension of Mobile IP that enables mobile hosts to use multiple care-of addresses simultaneously. The extension enhances network connectivity by enabling the mobile host, the home agent and correspondent hosts to evaluate and select the best connection. A proposed gateway architecture using M-MIP that integrates wired IP networks with ad hoc networks is described. The M-MIP and gateway architecture using the RVM and RNL metrics have been validated with simulation studies and results are presented.     

移动IP网络中基于遗传算法的多步寻呼策略及性能分析

在移动IP网络中,层次移动IP协议可降低移动IP位置管理的信令消耗。该文研究支持寻呼的HMIPv6,提出了时延限制下的多步寻呼策略以及基于遗传算法的多步寻呼方案——根据移动节点的位置概率分布,采用遗传算法对寻呼区域内的所有子网进行分组,每步寻呼一个组,使平均寻呼信令开销达到或接近最优。此外,对HMIPv6、单步寻呼的HMIPv6以及基于遗传算法的多步HMIPv6寻呼方案的信令开销进行了比较分析,得出寻呼节省信令开销的必要条件。最后,给出一组数值结果以说明所提出的寻呼策略的有效性。     

Effect of dormant registration on performance of mobility management based on IP paging in wireless data networks

Unlike traditional cellular networks, which provide mainly voice services, there is, at present, no method that enables the effective management of terminal mobility for both active and idle mobile terminals in data networks. Although IP paging has been introduced to reduce power consumption of dormant mobile terminals, there is no concern to design an effective IP paging method for real wireless environments. Therefore, we propose a new dormant registration based IP paging method and analyze the effect of the dormant registration threshold used in IP paging on the performance of mobility management. Moreover, we demonstrate the importance of selecting an appropriate value for the dormant registration threshold.     

基于DNS的代理移动IPv6位置管理机制

Proxy Mobile IPv6 (PMIPv6) is designed to provide a network-based localized mobility management protocol, but it does not handle the global mobility of hosts. In this paper, we propose a location management scheme based on Domain Name System (DNS) for PMIPv6 which can support global mobility by using DNS as a location manager. In addition, to support large numbers of mobile terminals and enhance network scalability a paging extension scheme is introduced to PMIPv6.To evaluate the proposed location management scheme, we establish an analytical model, formulate the location update cost and the paging cost,and analyze the influence of the different factors on the total signaling cost. The performance results show that our proposed scheme outperforms the basic PMIPv6 under various parameters in terms of reducing the signaling overhead and the proposed scheme reduces signaling overhead compared to the basic PMIPv6.     

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.     

Information-Theory Based Optimal Location Management Schemes for Integrated Multi-System Wireless Networks

In a multisystem environment where a mobile node can utilize multiple interfaces and simultaneously connect to multiple providers, new opportunities exist for efficient location management strategies spanning heterogeneous cellular wireless networks. In this paper, an integrated framework is developed for location management in such a multi-system, fourth generation (4 G) wireless networks. This information-theoretic framework allows each individual sub-system to operate fairly independently, and does not require the knowledge of individual sub-network topologies. An efficient location management in such a loosely coupled network is designed by having a mobile node view its movement as a vector-valued sequence, and then transmit this sequence in an entropy coded form to the network. We demonstrate how an intelligent, integrated paging strategy must consider the joint residence probability distribution of a mobile node in multiple sub-networks. We prove that the determination of an optimal paging sequence is NP-complete, and also propose an efficient greedy heuristic to compute the paging sequence, both without and with bounds on the paging delay. Three different location tracking strategies are proposed and evaluated; they differ in their degrees of centralized control and provide tradeoff between the location update and paging costs. Simulation experiments demonstrate that our proposed schemes can result in more than 50% savings in both update and paging costs, in comparison with the basic movement-based, multi-system location management strategy.     

A Location Management Scheme Using Direction Characteristics of Mobile Terminals in Mobile Communication Networks

Recently, as the number of mobile terminals (or users) keeps explosively increasing, the location management to track the mobile terminals in mobile communication networks is becoming more important. However, previous schemes have used static location information without any consideration about the moving direction of a mobile terminal. For a fixed paging area, this results in unnecessary pagings, thus increasing the location management cost. In this paper, we propose a new location management scheme using the direction characteristics of a mobile terminal. The direction vector is defined to represent the moving direction of a mobile terminal and to compute a distance from the cell where a location update occurs to the current cell. The offset operation of direction vectors is also presented to represent the position of a mobile terminal in a paging area. This allows the mobile terminal to determine whether a location update will be performed or not. The mobile terminal can also vary its own paging area dynamically according to its moving direction whenever it moves across its paging area. In addition, we develop an analytical model for the proposed scheme which captures the direction characteristics of a mobile terminal based on the Markov model. Analytical results show that the proposed scheme can reduce location management cost by forming a dynamic paging area along the moving direction of a mobile terminal when compared to other schemes.Ui-Sung Song received his B.S and M.S. degrees in Computer Science and Engineering from Korea University, Seoul, Korea in 1997 and 1999, respectively. He is currently a Ph.D. candidate in Computer Science and Engineering from Korea University. Also, he is currently a researcher in the Research Institute of Computer Science and Engineering Technology at Korea University. His research interests include mobile IP, PCS networks, and ad-hoc networks.Joon-Min Gil received his B.S. and M.S. degrees in Computer Science from Korea University, Chochiwon, Korea in 1994 and 1996, respectively. He received his Ph.D. degree in Computer Science and Engineering from Korea University, Seoul, Korea in 2000. From 2001 to 2002, he was a visiting research associate in the Department of Computer Science at the University of Illinois at Chicago, U.S.A. He is currently a senior research engineer in Supercomputing Center at Korea Institute of Science & Technology Information, Daejeon, Korea. His recent research interests include distributed and mobile computing, wireless networks, Internet computing, P2P networks, and grid computing.Chong-Sun Hwang received his M.S. degree in Mathematics from Korea University, Seoul, Korea in 1970, and his Ph.D. degree in Statistics and Computer Science from the University of Georgia in 1978. From 1978 to 1980, he was an assistant professor at South Carolina Lander State University. He is currently a full professor in the Department of Computer Science and Engineering at Korea University, Seoul, Korea. Since 2004, he has been a Dean in the College of Information and Communications at Korea University. His research interests include distributed systems,distributed algorithm, and mobile computing systems     

Impact of the location area structure on the performance ofsignaling channels in wireless cellular networks

The authors consider connection-oriented wireless cellular networks such as IS-54, IS-95, GSM, and wireless ATM networks. These are connection-oriented digital networks which employ separate radio channels for the transmission of signaling information. A forward signaling channel is a common signaling channel assigned to carry the multiplexed stream of paging and channel-allocation packets from a base station to mobile stations. For wireless ATM networks, paging and virtual-circuit (VC) allocation packets are multiplexed across the forward signaling channels as part of the VC setup phase. A reverse signaling channel, which employs a contention-oriented medium access algorithm, is used by mobile stations to send channel-request and location-update packets. A location area is a region which includes a specified set of adjacent cells; it is used to track the location of mobile stations. Mobile units must reregister as they cross the boundary of a location area. The channel setup and paging response times are critical performance factors in the design of the signaling subsystem. A location area structure must be suitably selected to ensure that acceptable levels of such performance functions are achieved. A network which employs small location-areas will experience a high rate of location updates, while larger location areas lead to higher traffic intensities of paging messages. The authors overview a method for calculating the performance behavior of signaling messages. Subsequently the impact of the location area structure on the performance of the signaling system is investigated     

Optimal decision strategies for paging in mobile cellular networks

A high‐level technical survey of paging in mobile cellular communication networks is presented in this paper. We view paging as an optimal decision problem and explore different strategies based on sequential decisions. The examined schemes concentrate on different perspectives of the problem, depending on the type of decisions and the amount of information available or exploitable by the system. This approach provides a useful categorization and an easy conceptual basis for their theoretical investigation, necessary for the deployment of advanced paging algorithms. Because of its suggested generality, the discussed framework is also laid as reference for further research. As modern networks evolve, more emphasis will be given towards optimization in all aspects of a network system. The schemes presented greatly reduce paging costs and can be used in cooperation with known location update strategies to make part of a real network location management system. Copyright © 2006 John Wiley & Sons, Ltd.     

User Independent Paging Scheme for Mobile IP

Multi-step paging has been widely proposed in personal communications services (PCS) systems to reduce the signaling overheads. Similar ideas can be applied to Mobile IP to provide IP paging services. However, current proposed multi-step paging schemes are user dependent under which the partition of paging areas and the selection of paging sequence are different for each user. The performance of a user dependent paging scheme for individual users may be affected by many factors. It is often difficult to achieve perfect performance for each user. In addition, when multiple users are paged at the same time, user dependent paging schemes may consume significant system resources. This paper introduces a user independent paging scheme where the paging criterion is not based on individual user information. The goal of user independent paging is to provide satisfactory overall performance of the whole system, when personalized optimal performance for each user is hard to obtain. The user independent paging scheme is proposed for IP mobility for its easy implementation and convenient combination with paging request aggregation. The paging criterion adopted is the mobility rate of each subnet determined by the aggregated movements of all mobile users. In order to implement the proposed scheme, a concept of “semi-idle state” is introduced and the detailed solution for obtaining mobility rate is presented. Analytical results show that when paging one user at a time, the performance of the proposed user independent paging scheme is comparable to that of the paging schemes based on perfect knowledge of user movement statistics. When paging multiple users simultaneously and when the knowledge on individual user behavior is not perfectly accurate, the proposed scheme has remarkable advantages in terms of reducing the overall paging cost. Jiang Xie received her B.E. degree from Tsinghua University, Beijing, China, in 1997, M.Phil. degree from Hong Kong University of Science and Technology in 1999, and M.S. and Ph.D. degrees from Georgia Institute of Technology in 2002 and 2004, respectively, all in electrical engineering. She is currently an assistant professor with the Department of Electrical and Computer Engineering at the University of North Carolina-Charlotte. Her current research interests include resource and mobility management of wireless networks,QoS provisioning, and next-generation Internet. She is a member of IEEE and ACM.     

移动GSM网络寻呼成功率参数优化

移动通信的网络质量越来越受到关注,运营商对网络性能指标的稳定性要求越来越高,尤其是涉及到用户感知的指标,例如寻呼成功率、接通率、掉话率等,都提出了很高的要求。文章对影响用户感知的重要指标寻呼成功率进行了分析。从分析影响GSM网络寻呼成功率的原因人手,找到寻呼成功率的参数优化方法。通过无线寻呼参数的优化,使寻呼成功率明显提高,达到预期的目的,提高用户感知。     

A Combination of Optimal Partitioning and Location Prediction to Assist Paging in Mobile Cellular Networks

The correlated both in space and time user mobility behavior can aid significantly in the localization of a moving terminal in the network coverage area. However, there is always some uncertainty in mobile user position and a network-wide search cannot be done. Therefore, a predictive paging scheme must always be combined with a location update strategy and a compatible algorithm to conduct the search. In this paper, we introduce a new strategy that combines an optimal partitioning of the location area (LA) with a model to predict user movements, based on the additional information of the cell where the last interaction between the network and the terminal took place. We study the performance of the strategy under delay bounds and different mobility and call arrival characteristics. It is found that the new scheme further minimizes signaling costs and enhances previous sequential paging algorithms.     

关于TMSI寻呼与IMSI寻呼性能分析

随着移动用户的持续增长和手机新业务的不断推广,移动通信系统的寻呼负荷日益加重。以移动用户漫游被叫时的呼叫流程为例,分析IMSI寻呼和TMSI寻呼的原理,对比两种寻呼方式对网络性能影响,提出一种评估寻呼方式的量化计算方法。通过对寻呼容量较为紧张网元的试验证明,该方法可以科学指导寻呼方式的优化工作,提高移动通信网络的系统寻呼容量,改善移动通信系统寻呼性能。