Operations standards for global ATM networks: network element view

The International Telecommunication Union (ITU) has completed work on a series of standards on asynchronous transfer mode (ATM) equipment functional operations and network element management. The objective of these standards is to enable flexible design and interoperability of network elements for use in a global ATM network, independent of any specific implementation. This article discusses these standards with respect to their development and application in planning ATM networks. Specifically, it addresses the following: the modeling approach taken in the development of the ITU standards, key operational features specified in the ATM network element functional model, and the capabilities of the ATM network element management interface. Examples of ATM equipment are provided to illustrate how the functional models specified in the ITU standards may be used by network planners and equipment manufacturers to specify and develop ATM equipment tailored to specific needs, while ensuring network interoperability. The article concludes with some points on the future enhancement of these and related ATM equipment operations standards     

Managing networks in a multi-vendor environment

The Unified Network Management Architecture (UNMA), developed by AT&T to provide a base for network management in a multilevel environment, is discussed. The functions of data management addressed by UNMA are delineated. These comprise five functional areas recognized by the standards groups working in network management, namely configuration, faults, performance, accounting, and security, as well as the four functional areas of planning, operations, programmability, and integrated control specified by AT&T. The family of products introduced to support UNMA is described     

Intelligent network concepts in mobile communications

A mobile cellular network architecture that is based on intelligent network concepts is presented. Subscriber service mobility and call management attributes of the network, including location information retrieval and updating, authentication, call routing, handover, charging, and operations and maintenance, are discussed     

Operations planning strategies for new network services andtechnologies

An approach for using computer-based operations systems not only to support new telecommunications technologies and services but to facilitate their introduction is described. This approach is considered beneficial to telephone companies for two reasons. First, operations processes can become increasingly automated, allowing manual procedures to be phased out. Second, operations need to become an integral part of new network technologies and services to help provide the advanced telecommunications services that customers are demanding. It is demonstrated that joint planning for services, technologies, networks, and operations in the early stages of a project can result in rapid, but orderly, evolution     

面向服务的战场态势感知与协同技术研究

阐述了网络中心作战和先进信息技术条件下的新型战场态势图应用的任务需求,论述了先进的战场态势感知服务体系结构组成和能力,描述了态势图应用基本概念和数据模型,针对实际应用提出了基于门户服务的态势图协同标绘实现方法,为网络中心的联合作战态势感知提供了一种新的应用模式,并且能指导军事指挥组织更快和更好地同步规划和决策。     

Parallel plan execution with self-processing networks

A critical issue for space operations is how to develop and apply advanced automation techniques to reduce the cost and complexity of working in space. In this context, it is important to examine how recent advances in self-processing networks can be applied for planning and scheduling tasks. For this reason, we are currently exploring the feasibility of applying self-processing network models to a variety of planning and control problems relevant to spacecraft activities. Our goals are both to demonstrate that self-processing methods are applicable to these problems, and that MIRRORS/II, a general purpose software environment for implementing self-processing models, is sufficiently robust to support development of a wide range of application prototypes. Using MIRRORS/II and marker passing modelling techniques, we implemented a model of the execution of a “Spaceworld” plan which is a simplified model of the Voyager spacecraft which photographed Jupiter, Saturn, and their satellites. This study demonstrates that plan execution, a task usually solved using traditional AI techniques, can be accomplished using a self-processing network. The fact that self-processing networks have been applied to other space-related tasks in addition to the one discussed here demonstrates the general applicability of this approach to planning and control problems relevant to spacecraft activities. This work also demonstrates that MIRRORS/II is a powerful environment for the development/evaluation of self-processing systems.     

Pragmatic Introduction of Digital Switching and Transmission in Existing Networks

Introduction of digital Switching and transmission in existing networks depends on a multiplicity of factors, which are either network or system dependent. Digital network planning alternatives are discussed with reference to the introduction techniques (stand alone or integrated switching and transmission) and to the interconnection strategies with the analog network. A pragmatic approach with distributed tandem exchanges is proposed, and various network scenarios are presented with reference to different starting points including toll, local tandem, rural area and local terminal levels. A possible transition scenario for a progressive implementation of Integrated Service Digital Networks (ISDN) is also indicated. Finally, the main features and advantages of the pragmatic approach are presented.     

New concept and hierarchy for telecommunications standards

The factors leading to the formulation of standards to meet the rapid expansion of telecommunications in China are discussed. The categories chosen for the standards and their use in managing the deployment of telecommunications networks in China are described. The standards development approach used creates standards that involve the adoption of a layered approach to networking and the definition of sets of open standards for each of these layers. The resulting integrated network is divided into three layers: the bearer layer, support layer, and service layer. To provide this layered approach, four types of telecommunications standards, appropriate to the functional needs of organizations using the standards, have been developed. The four functional types are: telecommunications basic technical standards, engineering and construction standards, operations and maintenance standards, and telecommunications general standards     

The five challenges of managing global networks

The challenges facing corporations attempting to reach rapidly expanding global markets are discussed. It is argued that to meet those challenges, corporations must address five major areas of networking: technical knowledge, network design and planning, country-by-country service requirements, network management operations, and network management interoperability. Each area is described, and the ways in which corporations currently achieve a certain level of network management support as a basic element of their long-distance service are reviewed     

Implementation of a distributed architecture for intelligentnetwork operations

A plan for implementation of an integrated, distributed, architecture for support of intelligent network operations is described. The functional components are presented as generic building blocks, which can be combined in various ways to implement various services or specific network operations. The architecture permits flexible service offerings, allows enhanced service providers to access the local network, and allows a greater level of customer control. Transition from a traditional operations architecture to the distribution one is demonstrated     

基于优先级与时间裕度的卫星应急观测任务规划

应急观测是对地观测卫星为配合地面紧急行动而执行的任务,具有紧迫性、集中性等特点,为任务规划带来了困难。针对应急观测的特点,描述了影响任务规划的卫星资源及任务的主要属性,定义了考虑重要性与紧迫性的任务优先级,提出了一个反映任务紧迫性要求满足程度的属性———时间裕度。建立了任务规划模型,构造了一个基于优先级与任务时间裕度的规划目标,确定了一系列规划约束,并利用遗传算法对模型进行求解。通过与最大化任务重要度的常规任务规划进行对比可见,所建立的模型能够有效提高任务成功率。     

A low-cost cellular mobile communication system: a hierarchicaloptimization network resource planning approach

This paper deals with the optimization of the design and radio network resource planning for cellular mobile communication systems. The key element to be considered for mobile network planning is cost. A hierarchical optimization planning method (HOP) is utilized since there are so many factors like system performance, terrain features, base station parameters, and cost factors which are involved in the large-scale system design. We present a three-level optimization approach for designing a cellular mobile system. It determines the cell number, cell site allocation, and the specific base station parameters in order to minimize the total system cost and to comply with the required system performance. The problem is formulated as a large combinatorial optimization model which can determine the optimal number of cells and select the best base stations' locations. The simulated annealing approach is developed to solve the hard combinatorial problem. Simulation results demonstrate the feasibility and effectiveness of the HOP approach for radio network planning     

Network planning methodology and practice in China

The methods used in local network planning for the public telecommunications network in China are discussed. Network modeling, computer simulation, and planning software used in the planning process are described. A computer-aided planning tool for local telephone networks (CAPTLN), composed of three software modules that provide traffic forecasting, network optimization, and network economic analysis for the local network of the public switched telephone network (PSTN), is also discussed. Other tools are similarly used for all other parts of the PSTN network, such as international access, toll switching and trunking, signaling and synchronization     

A decomposition algorithm for capacity expansion of local accessnetworks

The authors study how to expand capacity of the local access network to meet projected demand over a given planning horizon at minimum cost. The alternatives for capacity expansion include both copper cable and digital multiplexer. They show how the problem can be modeled as an integer programming problem; however, the size of the problem for a typical network and the discontinuous cost structure of the expansion facilities preclude the use of a general purpose integer programming code to solve it. A decomposition approach that takes advantage of the structure of the problem and allows the problem to be solved in a reasonable amount of time is proposed. The solution methods described have been implemented and computational results are discussed. The algorithm forms a part of the network planning system NETCAP that has been in use since 1989     

Computer-aided planning of SS/TDMA network operation

A computer-aided approach to the planning of SS/TDMA network operation is proposed. SS/TDMA is a sophisticated satellite communication network based on an onboard switch matrix, whose operation planning is formulated as a large-scale scheduling problem. An overall planning and scheduling model is presented to deal with practical SS/TDMA systems, such as a two-frequency channel network and nondisjoint beam coverage. For systematic planning suitable for a computer-aided approach, the entire scheduling process is divided into several steps, for each of which an efficient mathematical model is proposed. A linear programming model is used for distribution of traffic on a beam-to-beam basis and the generated switching sequence is further refined by a model using the traveling salesman problem. Burst scheduling is carried out by the Bin packing algorithm and scheduling models for practical networks allowing transponder hopping and multidestination bursts. An algorithm called enhanced rescheduling is presented to further improve the scheduling capability of the existing methods. The performance of the proposed methods is demonstrated by simulation results     

PN短码在CDMA网络规划中的应用研究

PN(伪随机噪声)短码规划是CDMA(码分多址)网络设计中特有的问题,良好的PN码规划对于实现设计良好的网络至关重要。通过对同相偏干扰和邻相偏干扰这一对矛盾的分析和处理,介绍了PN码偏置规划的原理以及需要满足的基本条件,并提出了可行的规划方案。     

SONET ring applications for survivable fiber loop networks

Synchronous optical network (SONET) self-healing rings (SHR) are studied in the loop environment. SONET SHR architectures for loop feeder networks are discussed, focusing on three possible dual central office (CO) architectures for fiber loop networks, using SONET SHRs to reduce network costs and provide network service survivability. These architectures reflect an integrated planning concept for SONET networks that eliminates the boundary between the access network and the inter-office network. It is shown that the use of SONET SHRs makes it easy to evolve to a protected dual CO access architecture. Economic and survivability studies are discussed. The economic studies show that using the ring approach yields significant advantages over the traditional diverse protection approach in terms of cost and survivability, especially for the dual CO architectures     

WCDMA传输网络建设方案

随着中国3G的脚步声日益临近,几乎所有运营商都在开始规划即将建设的3G网络,3G网络的规划主要包括无线网络、核心网络和承载网络3个部分,其中承载网包括IP承载网以及传统的传输网,本文主要侧重于传输网,同时由于3G与2G的主要区别在UTRAN,因此本文将侧重探讨服务于WCDMA网络UTRAN部分的传输网建设方案.