Stability and Optimization Analysis for the PRMA Protocol for Voice and Burst Data Integration in a Personal Communication Network

Personal Communication Networks (PCNs) have become an important filed of activity and they are expected to play a fundamental role in next-generation telecommunication systems. In particular, the emerging personal communication services, such as portable computing, paging, personal e-mail, etc. have led to the need of an efficient integration of voice and data traffic in a same PCN by means of a suitable multiple-access scheme. This paper considers stability and optimization issues for the Packet Reservation Multiple Access (PRMA) protocol used for integrating voice and burst data traffic in a PCN. An important result here devised is that the optimized PRMA protocol permits to be achieved good performance even under heavy traffic load conditions.     

个人通信网和个人通信服务

作为第三代移动通信的创新概念“个人通信”被提出以来，个人通信网和个人通信服务从定义、理论、技术、设备等各方面得到不断发展和明显进步，得到全世界通信学界的极大重视，本文依据个人通信网的定义和现实发展，对个人通信网的研究发展方向，技术重点，实现个人通信服务所需求的功能和应用前景等进行讨论。     

小区分层依概率寻呼的位置管理策略

位置管理是移动通信领域的一个具有挑战性的问题,涉及到位置更新和位置查找操作.我国及其他国家目前正在使用的个人通信网络中,基本的位置管理策略(简称"基本策略")的位置查找操作采用的是,在整个位置区中同步寻呼移动台.由于所要寻找的移动台只在由众多小区所组成的位置区内的一个小区中,因此,"基本策略"会造成系统资源的极大浪费.本文给出一种对位置区内的小区进行分层,按移动台在各层小区的概率从大到小的次序,逐层进行寻呼的位置管理策略(简称"分层策略").在假定移动台在各个小区的逗留时间是符合一般概率分布的随机变量的条件下,推导出移动台处于各层小区的概率及"分层策略"所需搜索的小区平均个数公式.证明了"分层策略"的位置管理费用不大于"基本策略".     

Mobility management in next-generation wireless systems

This paper describes current and proposed protocols for mobility management for public land mobile network (PLMN)-based networks, mobile Internet protocol (IP) wireless asynchronous transfer mode (ATM) and satellite networks. The integration of these networks will be discussed in the context of the next evolutionary step of wireless communication networks. First, a review is provided of location management algorithms for personal communication systems (PCS) implemented over a PLMN network. The latest protocol changes for location registration and handoff are investigated for mobile IP followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed     

Integration of ATM call admission control and link capacity controlby distributed neural networks

An adaptive call admission control using neural networks was recently proposed for asynchronous transfer mode (ATM) communications networks. The author proposes adaptive link capacity control using neural networks. Neural networks are trained to estimate the call loss rate from link capacity and observed traffic, and link capacity assignment is optimized by a random optimization method according to the estimated call loss rate. The integration of adaptive call admission control and adaptive link capacity control yields an efficient ATM traffic control system suitable for multimedia communication services with unknown traffic characteristics. Computer simulation results using a simple network model are also given to evaluate the accuracy and efficiency of the proposed method     

Network architecture and traffic transport for integrated wireless communications over enterprise networks

A novel network architecture based on the IEEE 802.6 metropolitan area networks (MAN) is proposed to integrate the wireless and wired segments of a regional enterprise network (REN) within a city. This architecture functions like a distributed switch for all types of services, reducing traffic congestion by sharing the high capacity link dynamically and facilitating signaling, mobility management, call processing and network management through its distributed functions, transport facilities and broadcasting capability. It also serves as a peripheral gathering network of REN traffic for transport over a wide area ATM/BISDN, enabling integration of an enterprise's regional networks into a global EN. Two major wireless applications, i.e., wireless PABX (WPABX) and wireless LAN (WLAN) are discussed to illustrate the advantages of this MAN‐based architecture. Although a REN is likely to support a wide range of different services, voice and data will continue to be the predominant traffic generated by WPABXs and WLANs, respectively, and are also representative of isochronous and asynchronous multimedia traffic carried by future wireless networks. We compare the traffic capacity of several voice transport alternatives under integrated (voice/data) network traffic with various data traffic loads, and study voice and data integration under three different integration schemes by simulations. Results indicate that the MAN‐based architecture is most effective employing queue arbitrated (QA) access for asynchronous traffic, pre‐arbitrated access for constant bit‐rate isochronous traffic, and the new reservation arbitrated (RA) access for variable bit‐rate isochronous traffic, under a scheme that permits full sharing between QA and RA traffic. This revised version was published online in July 2006 with corrections to the Cover Date.     

ATM网络中语音编码和传输的新方案

本文针对未来新的ＡＴＭ通信方式,提出了一种新的语音可变速率编码和可变时延传输系统方案,为了将信号源和人耳听觉的特征,与ＡＴＭ网络的统计复用性相结合,实现语音的码率在缩和低时延传输,该方案将ＡＴＭ网络环境和语音编码系统中最优信号分析区间的选取、编码系统参数的确定相结合。文中基于一种新的分布熵进行信号特征判断,对输入信号构成不同的处理系统,具体编码由小波变换分带、多带二进树ＶＱ构成,输出码率可调,改变     

An efficient algorithm for the link allocation problem on ATM-basedpersonal communication networks

The personal communication network (PCN) is an emerging wireless network that promises many new services for the telecommunication industry. The proliferation of demands for extending wireless services to integrated services which supports the transmission of data and multimedia information has resulted in the need for broadband wireless systems that are able to provide service capabilities similar to those of wireline networks. The ATM cell-relay paradigm is one possible approach to provide broadband wireless transmission with PCNs using the ATM switching networks for interconnection of PCN cells. In an ATM-based PCN, the communication path between a pair of mobile terminals might be elongated due to the mobility of the terminals. The link allocation problem is that of allocating backbone links among ATM switches to reduce the effects of terminal mobility on the performance of ATM-based PCNs. Huang and Wang (1997) have shown that this problem is NP-complete. In this paper, we propose a new efficient heuristic algorithm for the link allocation problem. One novel feature of our algorithm is that we are able to derive sufficient conditions under which our algorithm is able to guarantee optimal solutions. Our empirical study shows that the average lengths of communication paths obtained by our algorithm are shorter than those obtained by Huang and Wang's algorithm. In addition, the number of successfully established paths obtained by our algorithm is significantly more than that obtained by the aforementioned     

PCS mobility support over fixed ATM networks

As broadband multimedia services and wireless services become popular, there is growing interest in the industry to support ATM over a wireless link, and wireless access to fixed ATM networks. We focus on the internetworking of PCS and ATM networks, in which the air interface remains one of the PCS standards and the backbone is an ATM network with mobility support. It is desirable to minimize the impact of the internetworking and mobility support on the existing/emerging PCS and ATM specifications. A network architecture, a protocol reference model, and signaling protocols for PCS mobility support over fixed ATM networks are described. They are compared against other implementation alternatives and the trade-offs are discussed. Some performance results of the proposed architecture are also presented     

Personal communications services

The history of the US Federal Communications Commission (FCC) examination of proposals to allocate radio frequency spectrum to a new and innovative range of services it calls personal communications services (PCS) is outlined. Personal communication networks (PCN), which will supply mobile two-way, mass-market communications services, the most advanced offering of the PCS area, and spectrum allocation for PCS are discussed. The results of a consumer market study of the potential for PCN services are also discussed     

Data communication in ATM networks

An increasing number of customers require LAN access with high bandwidth and low delay over long distances. To satisfy these needs, several high-speed network techniques have been developed. Asynchronous transfer mode (ATM) is superior compared to other networking technologies, as it offers high bandwidth and is scalable in the sense that the bandwidth capacity of an ATM system is not fundamentally limited to the technology itself. Initial ATM installations will operate as subnetworks of existing networks and MAC layer protocols. One of the main challenges in ATM is the transparent support of existing connectionless LAN services. Several activities have been launched within international standard bodies and forums to specify ways of providing data communication services over ATM. Most notable examples are Switched Multimegabit Data Service (SMDS) and the similar Connectionless Broadband Data Service (CBDS) supported mostly by public network service providers. But also other approaches such as IP over ATM, and LAN emulation that show more adherence to the existing local and campus area networking paradigms. The article presents the requirements and architecture of the LAN emulation service. It describes the alternative methods for carrying IP packets over ATM, a public broadband service architecture and CBDS. The traffic management aspects of the data communication services are also discussed     

Spread spectrum technology: a solution to the personalcommunications services frequency allocation dilemma

The spectrum allocation problems posed by the establishment of personal communications services (PCS) are discussed, and some conclusions are drawn from the recent experience of licensing personal communications networks (PCNs) in the UK. A proposal for spectrum sharing is presented, focusing on the criteria to be met and the use of code-division multiaccess technology for its implementation     

802.6 MAN based personal communications network over CATV plants

An infrastructure shared 802.6 MAN based personal communication network(PCN) is to be discussed. Considering the network configurations of CATV and 802.6 MAN based PCNs, a possible architecture is proposed. It is shown that the unidirectional dual buses can be implemented over star topological CATV distribution cable networks with only two cores. The design considerations related to the network capacity and the signaling loads for wireless personal communications are investigated with numerical example. The MAN partitioning is considered to extend the capacity of the network. An analytical method to evaluate the signaling loads of 802.6 MAN based PCNs is presented with a new mobility model. It is shown that the signaling traffic increased by partitioning is not the critical constraint for the feasibility of 802.6 MAN based PCN     

User Mobility Management in the PCS Network Through the Placement of Hierarchical Databases

The personal communication service (PCS) networkis the next generation wireless communication networkthat allows users to communicate with each other oraccess information in the network any time and anywhere. It is the integration of the cellulartelephone network, the conventional telephone network,and the digital communication network. User movementswithin the network coverage area must be tracked using a database. A hierarchical distributeddatabase architecture localizes database operationscaused by user movements and call setup requests, andreduces traffic in the signaling network. Placement of the database in the signaling networkaffects performance of the network. A new method ispresented to find the best database placement scheme fora given estimation of user movement and call setuprequest rates. This database placement scheme minimizesthe delays of messages resulting from user movements andcall setup requests in the signaling network.     

Chain authentication in mobile communication systems

Digital mobile telecommunication systems have become a future trend in personal communications services (PCS) networks. To satisfy the demand for high quality services, security functions, including the authentications of communication parties and the confidentiality of communication channels, must be embedded into mobile communication systems. This work presents an authentication scheme to support the security functions. The proposed protocol significantly improves the performance of authentications and ensures the security of mobile communications in a large-scale communication network with multiple service providers. This revised version was published online in June 2006 with corrections to the Cover Date.     

个人通信系统中的用户登记认证

个人通信系统(PCS)的智能网络层上每个结点的数据库采用全分布式结构。根据PCS的智能层数据库结构特点以及X.509目录认证架构,提出了一种移动用户登记认证方案。此方案克服了X.509所具有的“静态”特性,使其能够满足PCS用户移动性及终端移动性的要求。在进行用户登记认证的同时,用户与本地的访问网络之间还建立起一个秘密数据。基于这一秘密数据,用户与网络之间可以在呼叫建立阶段进行相互认证。这就避免了现有的移动通信系统(如GSM,IS-41等)呼叫建立阶段的认证受归属网位置登记数据库(HLR)控制的缺陷。因此,用于位置修订和查询的信令负荷大大减小;同时,有关骨干网络(如PSPDN或共路信令网)安全的假定也可以被取消。     

Integration von ATM und Internet — die neue technologische Herausforderung?

Although ATM was conceived as a networking technology for multimedia communications currently ATM is to large extent employed as a backbone technology in the wide area telephone networks and for carrying Internet traffic between conventional LANs. Consequently, there is a large motivation to integrate ATM technology with Internet technology. It has to be expected that the basically different communication concepts “connectionless” and “connection oriented” will be increasingly merged in the future. This merging is already highlighted by the ongoing discussion of an efficient ATM/IP-integration. The purpose of this paper is to investigate the lates advances in ATM technology as well as in Internet technology and the different approaches for ATM/IP integration.     

数字通信网技术的发展历程

本文简述通信技术的发展过程，分别说明数字电话通信网，公用和专用数据通信网，窄带和宽带综合业务数字网，通信网信令系统，全光通信网，智能网和个人移动通信网的技术进展。最后总结未来的Ｂ－ＩＳＤＮ是宽带、高速的光纤通信网和未来的ＰＣＮ是全球移动卫星的微波通信网，两者联合组成国家通信网基础结构。     

Analysis and Comparison of Location Strategies for Reducing Registration Cost in PCS Networks

In mobile environments, a personal communication service (PCS) network must keep track of the location of each mobile user in order to correctly deliver calls. A basic scheme used in the standard IS-41 and GSM protocols is to always update the location of a mobile user whenever the mobile user moves to a new location. The problem with this approach is that the cost of location update operations is very high especially when the mobile user moves frequently. In recent years, various location management strategies for reducing the location update cost have been proposed. However, the performance issue of these proposed algorithms remains to be investigated. In this paper, we develop two Markov chains to analyze and compare the performance of two promising location update strategies, i.e., the two location algorithm (TLA) and the forwarding and resetting algorithm (FRA). By utilizing the Markov chain, we are able to quickly answer what-if questions regarding the performance of PCS networks under various workload conditions and also identify conditions under which one strategy can perform better than the others. Using the cost due to location update and search operations between two successive calls to a mobile user as a performance measure, we show that when the mobile user exhibits a high degree of locality and the mobile user's call-to-mobility ratio (CMR) is low, TLA can significantly outperform both FRA and IS-41. On the other hand, when CMR is high, FRA is the winner. Furthermore, unlike TLA which may perform worse than IS-41 at high CMR values, FRA at identified optimal conditions can always perform at least as good as IS-41, suggesting that FRA over TLA should be used as a generic scheme in reducing the location cost in the PCS network to cover all possible per-user CMR values.     

A Fast Handoff Management Scheme in ATM-Based Personal Communication Networks

Future wireless personal communication networks will likely have infrastructures based on asynchronous transfer mode (ATM) networks. It is a challenge to support seamless, fast handoffs in such an environment. We propose a fast handoff management scheme using permanent virtual connections (PVCs) reserved between neighboring base stations (BSs). In the proposed scheme, the handoff can be quickly performed by rerouting the communication path via the PVCs. Handoff calls are distributively controlled only by the corresponding BSs without the involvement of any ATM switches. ATM cell sequence integrity during handoff can be maintained by the BSs. In order to dimension the PVC, we analytically derive the probability of handoff blocking due to the lack of PVCs. We give some numerical examples of PVC dimensioning. The proposed scheme can be utilized in the future IMT-2000 networks accommodating various narrowband services in the range of several kbps to several hundreds kbps.