RVSP基于H.323协议VoIP系统的QoS应用

本文着重介绍了资源预留协议(RSVP)在H.225的RAS协议、H.245协议和RSVP的同步问题等几个方面的应用策略,对基于H.323的VoIP系统中RSVP过程进行了较为详细的分析。     

基于H.323协议的IP电话网关的QoS设计与实现

首先介绍了RSVP的基本框架，基本原理和主要特点，然后分别从H．225的RAS协议、H．245协议和RSVP的同步问题等方面，对IP电话网关的RSVP过程进行了较为详细的分析，最后阐述了RTP／RTCP协议里与QoS相关的一些细节。     

RSVP协议端到端QoS控制机制的研究

1 引言为了支持在Internet/Intranet上开发多媒体应用,IETF开发了两个支持多媒体通信的传输协议:实时传输协议RTP和资源保留协议RSVP,这两种传输协议都是在无连接协议UDP上提供端到端实时传输服务的、本文主要讨论RSVP协议。 RSVP目标是在网络中为建立特定的服务质量(QoS)提供一种方法,以减小网络传输延迟。RSVP定义了一种称为会话(session)的特殊QoS控制关系,支持端到端的QoS协商和控制。 RSVP的基本原理是发送者在发送数据前首先发送Path消息与接收者建立一个传输路径,Path     

一种基于RSVP协议的资源提前保留技术

IETF提出使用RSVP协议确保能在Internet上得到QoS。但由于RSVP协议是面向接收者的，接收者可能会由于不清楚整个路径的情况而做出超要求，从而使得需求被拒绝的机会变大。提出了一种基于RSVP的资源提前保留技术，能在一定程度上弥补RSVP资源预留模式的不足。     

流媒体系统引入RSVP协议的实现方法

RSVP协议在具有QoS保证的应用程序实现中的复杂性成为RSVP协议应用到流媒体系统中的一个瓶颈.提出一种在基于Windows平台的流媒体系统中引入RSVP协议的实现方法,此方法在实现了RTP/RTCP协议的流媒体系统基础上,不必修改源码,通过一种RLR（RSVP library redirection,RSVP库重定向）方法,结合微软Winsock2中的常规服务质量（generic quality of service,GQoS）技术,为流媒体预留带宽.     

Windows系统IP网络上的QoS分析

当前网络服务质量的热点之一——RSVP协议和使用RSVP协议的应用接口GQoS。描述了QoS组件和结构,使用Winsock2GQoSAPI编写请求QoS的应用程序。     

基于RSVP与MPLS集成的QoS保障机制

文章分析了IntServ/RSVP与DiffServ这两种IP网络的QoS保障机制的原理,并对这两种体系结构进行了比较,说明了各自的优缺点,同时也指出了这两种机制的适用环境。提出了一种利用扩展RSVP协议与MPLS技术相结合的基于IP网络的QoS保障机制。最后,给出了利用RSVP协议建立标记交换路径(LSP)的步骤。利用该方法可以很好地保障IP网络的QoS。     

网际多媒体传输协议

随着多媒体数据在Internet网络上传输应用的增多,传统的网络协议已经不能胜任新的要求。针对这一问题,分析了传输多媒体数据的关键协议RTP/RTCP,RSVP和RTSP,并分别讨论了各个协议的特点、功能和工作原理等。     

一种基于软件代理的QoS管理技术

IETF提出使用RSVP协议确保能在Internet上得到QoS。但是,目前已经存在一些网络资源,如路由器,不支持RSVP协议,如果在路由器路径上存在这种网络资源,则不能确保端端传输质量。本文提出了一种基于软件代理来管理QoS方法,它遵循开放式可编程网络结构,能弥补在Internet上资源预留模式RSVP的不足。     

资源预留协议在移动IP中的应用

文中讨论了在移动环境下标准RSVP所存在的问题，并对现有的几种解决方案进行了描述和分析。随后介绍了简单资源预留协议的工作过程，并提出了一种在移动IP中提供实时服务QoS的简单资源预留协议与移动IPv6的集成模型。     

利用RSVP隧道高效实现INTERNET的服务质量请求

在ＩＮＴＥＲＮＥＴ上应用ＲＳＶＰ时,新增通信量和时空开销问题是ＲＳＶＰ研究的关键问题之一。文中提出了利用ＲＳＶＰ隧道和ＱｏＳ请求聚合体解决此问题的方案,核心内容是：ＱｏＳ请求聚合体代表多个具有指定特征的ＲＳＶＰ会话消息,隧道段的路由器的ＲＳＶＰ模块对聚合体会话消息设置软状态而不理会构成聚合体的单个会话消息、构成聚合体的每个一ＲＳＶＰ会话消息被封装后以普通数据包形式通过隧道段。     

一种RSVP结合Agent保证QoS的方案

QoS是近来网络技术研究的一个热点,RSVP是目前流行的几种QoS协议之一,目前主要用于小型私有网络或互联网的边缘区域,其中一个重要原因是因为并非所有的路由都支持RSVP,对于不支持RSVP的结点处,服务退回到尽力转发,因此很难保证端到端的服务质量。在分析了RSVP协议的基础上提出了结合Agent来保证QoS。     

Towards an improved readability on mobile devices: evaluating adaptive rapid serial visual presentation

Can readability on small screens be improved by using adaptive Rapid Serial Visual Presentation (RSVP) that adapts the presentation speed to the characteristics of the text instead of keeping it fixed? In this paper we introduce Adaptive RSVP, describe the design of a prototype on a mobile device, and report findings from a usability evaluation where the ability to read long and short texts was assessed. In a latin-square balanced repeated-measurement experiment, employing 16 subjects, two variants of Adaptive RSVP were benchmarked against Fixed RSVP and traditional text presentation. For short texts, all RSVP formats increased reading speed by 33% with no significant differences in comprehension or task load. For long texts, no differences were found in reading speed or comprehension, but all RSVP formats increased task load significantly. Nevertheless, Adaptive RSVP decreased task load ratings for most factors compared to Fixed RSVP. Causes, implications, and effects of these findings are discussed.     

RSVP Browser: Web Browsing on Small Screen Devices

In this paper, we illustrate the use of space-time trade-offs for information presentation on small screens. We propose the use of Rapid Serial Visual Presentation (RSVP) to provide a rich set of navigational information for Web browsing. The principle of RSVP browsing is applied to the development of a Web browser for small screen devices, the RSVP browser. The results of an experiment in which Web browsing with the RSVP browser is compared with that of a typical WAP browser suggests that RSVP browsing may indeed offer alternative to other forms of Web browsing on small screen devices.     

动态移动RSVP在移动IP网络的研究

介绍RSVP协议基本原理,提出一种基于移动ip网络环境的动态移动RSVP扩展方案.该方案在蜂窝中通过使用移动代理,利用移动ip网络支持组播和GPS预测节点移动,根据信号传输距离计算出移动节点本地蜂窝链路可用时间,建立当前范围预留和预范围预留两条路径,自动进行数据传输切换.实验结果表明,在移动ip网络使用动态移动RSVP比移动RSVP在数据包的投递率和延迟时间方面表现更好.     

Optimizing the reading of electronic text using rapid serial visual presentation

The focus on communications technology in recent years has led to the question of how to best display electronic text onto small-screened devices. Past studies have shown that the compact method of rapid serial visual presentation (RSVP) is efficient but not well liked. Two experiments were conducted to explore ways of improving the preference for and feasibility of RSVP. In experiment 1, the effects of a completion meter, punctuation pauses, and variable word duration were studied. Although the sentence-by-sentence and normal page formats were still superior, post-experiment ratings indicated that punctuation pauses improved user preference for RSVP, and its preference increased in general with practice. In experiment 2, a modified RSVP condition included a completion meter, punctuation pauses, interruption pauses and pauses at clause boundaries. This condition was significantly preferred to a normal RSVP condition. The present enhancements may increase the feasibility of using RSVP with small displays.     

A performance study of RSVP with proposed extensions

Resource ReSerVation Protocol (RSVP) was developed as an intended key component for the evolving Internet, and in particular for the Integrated Services architecture. Therefore, RSVP performance is crucially important; yet this has been little studied up till now. In this paper, we target two of the most important aspects of RSVP: its ability to establish flows and its steady-state overhead. We first identify the factors influencing the performance of the protocol by modelling the establishment mechanism. Then, we propose the principles of a Fast Establishment Mechanism (FEM) aimed at speeding up the set-up procedure in RSVP. We analyse FEM by means of simulation, and show that it offers improvements to the performance of RSVP over a range of likely circumstances. We also present the principles of a simple mechanism aimed at reducing the steady-state (i.e. refresh) message overhead of RSVP.     

基于传输路径的RANDP部署策略(TPBDS)

设计了支持RSVP协议动态部署的RSVP主动网络部署包(RANDP)及其封装格式,提出了两种RANDP包的部署策略,即点到点的部署策略EEDS和基于传输路径的RANDP部署策略TPBDS。对两种RANDP包部署策略的带宽消耗做了定量分析。分析表明,一般情况下,在RSVP协议部署过程中,采用TPBDS策略比采用EEDS策略要节省带宽。     

基于RSVP的高速网络传输

随着因特网的发展,网络应用系统对传输的实时性提出了越来越高的要求,保证关键网络业务的高速传输是迫切需要解决的难题。本文在研究ＲＳＶＰ协议的基础上,分析了 网络协议接口,设计并实现了ｒｓｖｐｄ守护进程和实时ＡＰＩ接口,建立ＲＳＶＰ的高速网络传输测试实验环境,并验证了该网络的实时特性。