论文标题:ATM接入设备相关软件研究与实现
Satellite Channel Dynamic Backup System System Design
论文作者 温海波
论文导师 李乐民,论文学位 硕士,论文专业 通信与信息系统
论文单位 电子科技大学,点击次数 138,论文页数 114页File Size9078k
2002-01-01论文网 http://www.lw23.com/lunwen_1487642/ ATM接入设备;虚拟设备驱动程序;网卡;调度算法;帧中继;实时操作系统
ATM access device,Virtual device driver (VxD),Network Interface Card (NIC),schedule algorithm,Frame Relay (FR),RTOS
近年来，因特网的爆炸性发展对通信网的建设有很大影响，促使交换体制向分组化发展。在骨干通信网络上采用IP Over ATM，还是IP Over SDH或IP OverWDM，引起了争论。ATM的优点是能较细地提供带宽，较能保证各种业务的服务质量，有人认为适于构建多业务通信平台。某些以电信为背景的运营公司采用IP+ATM和MPLS(多协议标记交换)，以适应多种用户需求。通信设备制造公司也并不放弃ATM，而且ATM的有关技术，例如交换结构、公平排队、拥塞控制等，对研制IP交换路由器也有裨益。 本课题来源有两个：一是来自“九．五”课题“ATM网络和交换技术研究”的“ATM用户接入设备研究”子课题，主要涉及ATM网卡相关技术的研究及实现。用户接入设备要求多种业务通过它接入网络，通过网卡对各种业务数据进行复／分接。ATM交换机在信元级进行QoS处理，为了使应用程序得到QoS，必须在终端上处理ATM层协议、AAL层协议以及高层协议。ATM网卡完成物理层、ATM层以及SAR(分段与装配)层功能。网卡驱动程序控制着网卡的通信过程，并为上层程序提供应用编程接口(API)。二是来自一研究所的项目“帧中继／ATM网络互通功能模块的实现”。 本文的研究有：1、Windows98开发了ATM网卡驱动程序，并提供传输层API接口，实现了可靠传输、实时传输，支持AAL0、AAL3／4、AAL5适配类型，支持CBR、VBR、UBR等业务，并且可带宽实现动态分配。2、在ATM网卡驱动程序基础上，开发基于AAL5适配协议的视频点播系统模型以及简单的文件传输。3、利用ATM网卡驱动程序和NDIS等技术实现以太网接入ATM网络。4、帧中继由X．25简化而来，与ATM技术有很多相似之处，帧中继用于比较低速的网络，需要实现与ATM网络的互连互通。5、目前某ATM网交换机不支持多播功能，但由于要在该网上实现视频会议、电子白板等多播业务，我们需要为ATM网络实现多播功能。考虑到帧中继与ATM的互通以及多播服务器的数据转发率比较大，需要用实时操作系统实现这些功能。 在本课题中我们掌握ATM网卡软件控制技术、Windows操作系统内核编程 中文摘要一技术、为虚通道分配带宽的信元调度算法、通过NDIS接入以太网、帧中继与ATM互通技术以及实时操作系统下的编程技术等关键技术。取得了以下成果： ．实现了 ATM网卡驱动程序（Wndows98／psosystem）o ．AALS方式接入多路高速数据文件传输系统。 ．实现ATM上的视频点播。音视频效果良好，达到ATM上视频点播最简 模型效果。 t 实现以太网接入。计算机可以通过ATM软件接人设备一ATM网络一 ATM软件接入设备接入Internet，享受Internet带来的各种服务，包括视 频点播、Web访问。在 10M以太网环境下，当以太网帧长度为 1518byte 时，最高转发速率为9．84Mbit／S。 t 提出两种解决ATM网上多播问题的方案，并实现之。其中ATM多播服 务器功能模块可以直接接于ATM交换机实现多播功能。所作系统支持 “交互式多媒体信息系统”业务的接入。 ．实现了FR／ATM互通
In recent years the explosive growth of Internet has beening influencing the construction of telecommunication networks, and there emerges one trend for switch architecture to move to be parcketized. IP over ATM, IP over SDH, or IP over WDM, which should be deployed in the backbone network, and this is a hot topic. But ATM has its advantages, ATM can dynamically provide many kinds bandwidths, and guarantee QoS (Quality of Service) for all kinds of services, so ATM is considered that it can be used to construct multi-service communication infrastructure. In order to meet the diverse needs, some corporations.are deploying IP+ATM and MPLS (Multi-Protocols Label Switching). And many telecommunications equipment vendors are still supporting ATM. In addition, some technologies in ATM, such as switch frabic, fair queueing, congestion control, are much useful for researching work of IP switch routers.My research task has two directions. The first direction is to do research on ATM access device in software mode. Multiple services are requested to enter the ATM networks through the access device, which are the functions of ATM NIC (network interface card) and some software based on ATM device driver. QoS is provided by ATM switch on cell level, but in order to provide QoS to applications, ATM layer protocol, AAL protocols and other high layer protocols should be implemented in the teminal. ATM NIC can cover the functions of physical layer, ATM layer and SAR (Segmentation and Reassembly sublayer). NIC device driver controls the process of network card, and at the same time the device driver provides some application programming interfaces (APIs) for high layers. Second, to implement the interconnection of FR/ATM.So there exit five major sub-tasks.1. The ATM NIC device driver must be implemented under Windows98, and can support AALO, AAL3/4, AAL5 adaptation types, and also support CBR, VBR, UBR services, what"s more, allocate bandwidth dynamically.2. Based on the ATM device driver, to develop one prototype for Video on Demand system; and also to implement one ftp system. In the two application, AAL5 is the optimal.3. Based on ATM device driver and NDIS technologies, to implement how Ethernet interconnect to ATM network. Here we adopt tunnel technology, from Ethernet data can go through ATM network transparently.4. Frame Relay is simpfied from X.25 and has some similiars with ATM. And it is relatively used in narrow bandwidth network, so it must be interconnected with ATM. There are two way to implementing interconnection, one is service interworking, the other is network interworking. Since there is much traffic between FR and ATM, we do this work under real time operating system (RTOS ).5. Now the ATM switch for strategical network could not provide multicast function, butmmulticast applications such as video conference and white board must be demoed in strategical network, so we must propose and implement solutions for multicast in ATM network.. There we propose two solutions, one is based on Ethernet/ATM interconnection, the other is to provide one multicast server for ATM switch which is implemented under RTOS.With going through with my research directions, many technologies are mastered such as ATM NIC software control technology, windows kernel programming technology, cell schedule algorithms, NDIS technology, FR/ATM interworking technologies and programming technologies under real time operating system. And the following are the achievementst:a) Have developed and implemented the ATM NIC device driver under Windows98 and pSoSystem.b) Have implemented one file transfer system which is based on AAL5 and could have multiple high speed channels simultaneously.c) Have developed one VoD prototype based on ATM device driver. The effect of this system is very good.d) Have implemented Ethernet-access-ATM system which can be called by ATM software multiplexer. One computer could enjoy diverse services, such as VoD, surfing on Web, by
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