Frame Relay to ATM interworking

Frame Relay is a well-established technology that has attracted a large number of customers world-wide. It is typically used to interconnect large, multi-site company local area networks (LANs). These data connections are usually at low to medium speeds. Asynchronous transfer mode (ATM) is a newer, broadband technology that is capable of very high speed LAN interconnection. In addition, it is arguably an ideal transport medium for legacy protocols such as Frame Relay.This paper describes the data transport features of each technology and discusses how ATM may be used to interconnect existing Frame Relay networks, and how an ATM user may exchange data with a Frame Relay user.     

Frame relay and ATM interworking

Frame relay has proven to be a very successful wide area networking service, and ATM is gaining momentum in the industry to become the preferred common backbone technology for supporting a wide variety of network services, including native ATM cell relay service and frame relay service. In the years ahead, ATM is poised to become the dominant networking technology. Since frame relay and cell relay services will coexist for a long time to come, it is imperative that the network and service interworking specifications be defined and implemented. This article focuses on the topic of frame relay and ATM cell relay service and network interworking. The authors provide the rationale, the standards-based methodology, the major open issues, and a likely evolution scenario for the interworking of frame relay and ATM cell relay networks and services     

ATM traffic management considerations for facilitating broadbandaccess

Traffic management in ATM nodes plays a key role in providing the capability to support a wide range of integrated services while utilizing network resources, such as buffer space and bandwidth, in an efficient manner. In many cases, the issues arising in ATM access devices are very similar to those encountered in larger ATM backbone nodes. In this article, major issues in the design of traffic management schemes are discussed. These include switch fabric design, buffering strategies, service scheduling disciplines, usage parameter control, buffer management schemes, call admission control, and feedback flow control     

Traffic management for connectionless services over ATM

This paper is concerned with the transport of connectionless traffic over ATM networks. Several architectures have been defined and standardized for this purpose, like LANE, CBDS, Classical IP or MPOA. However traffic management for resources optimization of these architectures remains mostly an open issue. One of the key problem there is to control – and dimension – the capacity of the required ATM virtual circuits. In [19,21], dynamic capacity allocation schemes have been defined for this purpose. They have shown great promise through simulation and analytical studies. In this paper, we analyze the behavior of a multiplexer with such dynamic capacity allocation schemes when fed by several bursty flows. EATA properties [5,18] are used to compute the loss probability seen by each individual multiplexed stream, extending the analytical analysis of [9]. The study gives insight into the usefulness of these schemes and highlights several interesting properties: namely, the reduction of inter‐dependency between multiplexed flows and the reduction of the average queue occupancy. Such properties allow a better multiplexing gain. The particular case of dynamic allocation schemes for TCP/IP is then discussed. This revised version was published online in June 2006 with corrections to the Cover Date.     

ATM Forum signalling protocols and their interworking

The ATM Forum is a key body which has been developing specifications for asynchronous transfer mode (ATM) technology over the past six years. It has produced a number of signalling specifications covering the user network interface, the inter-carrier interface and private networking environments. While work continues on 'fine-tuning' these agreements, there is still discussion about how they are used in large scale networks, and in particular on the interworking of public and private network environments.This paper reviews the current status of the relevant protocols and their scope. It then explores the issues related to their interworking and discusses the role of the proposed ATM internetwork interface (AINI) as an alternative internetwork or inter-carrier interface to its broadband intercarrier interface (B-ICI).     

A FIFO-based buffer management approach for the ATM GFR services

We investigate the TCP packet transmission over the ATM Guaranteed Frame Rate (GFR) service using a selective packet-discard with buffer vacancy tracking strategy and a packet-based push-out buffering scheme. Our approach is based on FIFO queueing discipline, it features fair sharing of available resources as well as feasibility in hardware implementation     

Charging for ATM services

Advances in analog and digital telecommunications technology have provided us with a wide range of telecommunications networks since the invention of the analog telephony network by Bell in 1876, such as wireless and wired CATV networks, local, metropolitan, and wide area networks, and the Internet; and a range of protocols to go with these networks, such as Internet Protocol or ATM. Charging for services delivered across these networks has always been an issue of major concern to providers and users of telecommunications services. The ability to charge accurately and efficiently for a service is directly related to the potential quality, value, flexibility, and customer care available to the customer, and, equally important, provides a means of survival, growth, and profitability to the provider. ATM is becoming a significant carrier of telecommunications services because its technology can accommodate a wide variety of services such as multimedia on demand, voice services, or videoconferencing, demanded by today's rapidly changing market. While there are many schemes in use for the charging of mobile and fixed telephony, the area of Internet charging and, in particular, ATM charging is relatively uncharted to date. In this article we address the challenge of developing methods of charging for ATM services, and show solutions in the form of technical and commercial recommendations and a practical implementation of these recommendations     

ATM for narrowband services

ATM is a broadband fast-packet technology, but its modern technological base should make it less expensive than existing circuit switching systems once economies of scale are reached. The article examines the use of ATM to address the growth of emerging narrowband services such as frame relay. ATM's flexibility in supporting variable rates and levels of service make it an ideal network technology to carry multiple services. While B-ISDN services promise many benefits to users, major issues must be addressed before such services can be available on a large scale. Utilizing ATM as a backbone technology to support the growing capacity needs of emerging narrowband services could facilitate more rapid introduction of ATM into the network infrastructure and speed delivery of future BISDN services     

智能网与因特网互联业务及其实现

介绍了智能网(IN)与因特网间互联业务的业务种类，实现业务的体系结构、功能实体及其通信协议，并结合一个具体业务(ICW)阐述了互联业务的实现过程．     

Technology interworking for SMDS: from the DXI/SNI to the ATM UNI

As service providers introduce asynchronous transfer mode (ATM) into their networks, they are faced with the issue of technology interworking: for a given service, can a customer who has an ATM user-network interface (UNI) communicate with a customer who does not have an ATM UNI? For switched multimegabit data service (SMDS), technology interworking is well defined. In fact, SMDS is supported by several technology platforms that can interwork with each other. The three major platforms which support SMDS are: a frame-based platform based on the SMDS data exchange interface (DXI), a cell-based platform based on the IEEE 802.6-1990 standard, and a cell-based platform based on ATM. This article examines how SMDS is supported by each of these platforms and how these platforms interwork. Furthermore, this article presents how the major interworking functions required for these platforms appear to be straightforward for suppliers to implement,     

ATM测试技术

本文通过对ＡＴＭ网络中可能出现的故障的讨论，指出了对ＡＴＭ网络测试的必要性。并对ＡＴＭＰ比较突出的几个问题提出了解决测试的方法。     

Network resource management for enterprise wide multimedia services

The support of broadband multimedia applications over an enterprise network poses a broad range of networking challenges for efficient resource management, intelligent switching, and access control for distributed information. We propose two server-based scheduling algorithms, with low computational complexity, to guarantee multimedia information synchronization at the destination, with minimum presentation delays and buffer requirements. We outline a communication framework, highlighting the issues and challenges faced by today's enterprise networks to support multimedia services. We describe the proposed connection establishment and resource allocation schemes in resource-constrained enterprise networks. The objective is to manage the limited resources of the network for maximum utilization. Towards this end we present a dynamic capacity allocation scheme to support connections for multiple users. Specifically, we show that the channel capacity allocation problem can be formulated as a quadratic programming problem. This allocation scheme is implemented at each intermediate switch to dynamically determine the capacity allocation. The effects of interswitch rate mismatch and network delay offset scheduling have also been incorporated in the management framework. In addition, we introduce the concept of route selection based on the requested network quality of service     

我国互联互通的政策与实践

互联互通管理是基础电信业务市场引入竞争后出现的新生事物。为了打破电信行业的垄断,政府在不同的电信业务领域适度引入竞争,由于电信竞争触及了原有的运营企业在电信市场中所处的垄断、支配地位,触及了其切身利益,因而原有的运营企业对竞争、对竞争对手是不欢迎的,常常会利用其在互联互通中的重要作用向新兴的电信运营企业施加互联阻力,以此达到压制竞争对手的目的。在电信管制的诸多环节中,市场准入、号码频率审批等权力均掌握在政府手中,而互联互通的主动权则掌握在电信市场处于垄断或支配地位的运营企业手中。因此,互联互通管理是业界公认的管理难题。     

Resource management for QoS support in cellular/WLAN interworking

To provide mobile users with seamless Internet access anywhere and anytime/ there is a strong demand for interworking mechanisms between cellular networks and wireless local area networks in the next-generation all-IP wireless networks. In this article we focus on resource management and call admission control for QoS support in cellular/WLAN interworking. In specific, a DiffServ interworking architecture with loose coupling is presented. Resource allocation in the interworking environment is investigated/ taking into account the network characteristics, vertical handoff, user mobility, and service types. An effective call admission control strategy with service differentiation is proposed for QoS provisioning and efficient resource utilization. Numerical results demonstrate the effectiveness of the proposed call admission control scheme.     

Topological considerations of ATM networks

This article considers two hierarchical routing models based on the optimization of the size of topology databases and routing complexity, respectively. Some design guidelines are also suggested for an hierarchical PNNI structure of a network topology. Copyright © 1999 John Wiley & Sons, Ltd.     

公共ATM网络的要求

本文介绍了ＡＴＭ（异步转移模式）在公共网络中的作用，ＡＴＭ在公共网络中的发展方向，最后着重讨论了公共ＡＴＭ网络的要求。     

ATM技术在大型企业网络中的实践和应用

本文阐述异步传递模式通信技术 (ATM )在我国某大型企业网络中的实际应用 ,并探讨我国大型企业网络的技术发展途径。     

Performance evaluation of integrated services interworking: The ATM-DQDB case

Performance studies on LAN/MAN-BISDN interworking have mainly focused on the requirements of isochronous and connectionless services. In this paper we extend performance results to cover also the case of non-isochronous connection oriented (CO) services supported by the queued arbitrated (QA) mode of access of the DQDB protocol. Using this case we stress the more general issue of service integration impact on the interworking unit (IWU) architecture design in terms of protocol stacks and expected performance. We herein evaluate the performance of IWU architectures tailored to relay information in the lowest possible layer while implementing several service priority schemes and buffer management policies towards QoS objectives. The conditions under which the IWU design is efficient regarding performance, protocol complexity and implementation cost in this integrated services environment are identified.