共查询到20条相似文献,搜索用时 187 毫秒
1.
2.
DiffServ是解决宽带Internet QoS控制的一种可行方案,它在边界节点将不同的QoS要求映射成PHB。对每类具有相同PHB的IP业务流,应用VTRR公平调度算法。VTRR算法允许在竞争带宽的业务流中公平共享分配的带宽。将VTRR与RSVP结合使用,能为DiffServ提供QoS保证。 相似文献
3.
ORACLE WEB SERVER的结构及原理 ORACLE是世界上应用最广泛的数据库。ORACLE 提供了ORACLEWEBSERVER,使数据库和WEB有机的结合在一起。 ORACLE使用了一个WEB的监听器,这是一个WEB的服务器,是OARCLE主机上的HTT P引擎,管理从WEB浏览器进来的请求,传递给WEB请求代理器进行处理。当HTTP建立后,将它交还给WEB监听器,由WEB监听器完成HTTP文档传递给初始的命令请求者。可以把它看成ORACLE WEB SERVER与外界WEB浏览器的接口。它… 相似文献
4.
5.
在Windows95中,由于驱动程序ESCP24SC.DRV设计上的缺陷,致使LQ-1660K打印机不能双向打印。本文从分析ESCP24SC.DRV入手,绘出了通过修改ESCP24S.DRV入手,绘出了修改ESCP24SC.DRV而实现双向打印的方法。 相似文献
6.
在Windows95中,由于驱动程序ESCP24SC.DRV设计上的缺陷,致使LQ-1600K打印机不能双向打印。本文从分析ESCP24SC.DRV入手,绘出了通过修改ESCP24SC.DRV而实现双向打印的方法。 相似文献
7.
线性连续回归模型基于Laguerre多项式逼近的Markov参数估计 总被引:4,自引:0,他引:4
赵明旺 《数值计算与计算机应用》1995,(2)
线性连续回归模型基于Laguerre多项式逼近的Markov参数估计赵明旺(武汉钢铁学院自动化系)MARKOVPARAMETERESTIMATIONFORLINEARCONTINUOUSREGRESSIVEMODELSVIALAGUERRE-POLY... 相似文献
8.
2-D SHAPE BLENDING OF NURBS CURVE SHAPES 总被引:2,自引:0,他引:2
2-DSHAPEBLENDINGOFNURBSCURVESHAPESJinXiaogang;BaoHujun;PengQunsheng2-DSHAPEBLENDINGOFNURBSCURVESHAPES¥JinXiaogang;BaoHujun;Pe... 相似文献
9.
UNIX是当前世界上使用最普遍、影响最深远的主流操作系统,SCOUNIX一自以其植根于Intel平台、接近于大众的特色而名满天下。SCO公司综合了以前的OPENSERVER和UNIXWARE最近推出了OPENSERVER5.0.5版本,因此它是目前市... 相似文献
10.
由应用程序指定通信服务质量是网络多媒体应用对通信技术提出的主要要求。本文基于新一代IP协议IPV6,资源预留协议RSVP,Native ATM和WinSock2,在传统网络和ATM网络上提出一个支持由应用程序指定QoS的多媒体通信软件平台。 相似文献
11.
针对无线移动通信的特点,提出了一种在移动IPv6网络中保障用户通信服务质量的资源预留新方案Fast RSVP.该方案采用跨层设计的思想,将两个不同层次的模块:移动IPv6模块和RSVP模块结合起来,通过在两个模块之间增加一些原语使得二者配合工作以保证移动用户的通信业务质量.Fast RSVP方案引入了邻居隧道提前资源预留、优化路径资源预留、切换预留、路径融合等一系列新机制.仿真实验结果表明,与其他移动环境中的RSVP扩展方案相比,该Fast RSVP方案在支持无线移动通信方面具有如下优势:(1)能够实现移动节点带有服务质量保证的快速切换;(2)能够避免移动IP切换过程中三角路由和重复预留造成的资源浪费;(3)能够区分不同类型的切换预留请求,在保证网络整体性能的前提下显著降低因为切换而导致的服务中断率. 相似文献
12.
Qos是近来网络技术研究的一个热点,而RSVP是目前流行的几种Qos协议之一,它能够很好地获得服务质量。但是由于目前很多路由器不完全支持RSVP,使得服务会被退回而尽力转发,因此很难保证端到端的服务质量。本文在分析QoS的基础上,提出了结合Agent采保证Qos的方法,运用移动Agent结合RSVP来解决隧道问题。 相似文献
13.
Xiaobo Zhou Jianbin Wei Cheng-Zhong Xu 《Parallel and Distributed Systems, IEEE Transactions on》2006,17(8):838-850
A scalable e-commerce server should be able to provide different levels of quality of service (QoS) to different types of requests based on clients' navigation patterns and the server capacity. E-Commerce workloads are composed of sessions. In this paper, we propose a session-based two-dimensional (2D) service differentiation model for online transactions: intersession and intrasession. The intersession model aims to provide different levels of QoS to sessions from different customer classes, and the intrasession model aims to provide different levels of QoS to requests in different states of a session. A primary performance metric of online transactions is slowdown. It measures the waiting time of a request relative to its service time. We present a processing rate allocation scheme for 2D proportional slowdown differentiation. We then introduce service slowdown as a systemwide QoS metric of an e-commerce server. It is defined as the weighted sum of request slowdown in different sessions and in different session states. We formulate the problem of 2D service differentiation as an optimization of processing rate allocation with the objective of minimizing the service slowdown of the server. We prove that the derived rate allocation scheme based on the optimization guarantees client requests' slowdown to be square-root proportional to their prespecified differentiation weights in both intersession and intrasession dimensions. We evaluate this square-root proportional rate allocation scheme and a proportional rate allocation scheme via extensive simulations. Results validate that both schemes can achieve predictable, controllable, and fair 2D service differentiation on e-commerce servers. The square-root proportional rate allocation scheme provides 2D service differentiation at a minimum cost of service slowdown. 相似文献
14.
IPv6的出现为有QoS要求下移动IP中的切换问题提供了新的途径。提出一种基于双路候选并利用RSVP的移动ipv6切换方式。该方式通过建立直接从相应节点(CN)到家乡代理(HA)或是到移动节点(MT)的RSVP会话,解决了移动IP中的三角路由问题并保证QoS的要求。 相似文献
15.
给出了DiffServ网络的一种设计与实现,提出了一种有效的资源管理模型。在该模型中,存在一个带宽代理(Bandwidth Broker)同步多个边界节点的接纳控制,负责区分服务网络之间的SLA(Server Level Agreement)协商,进行路由器配置;边界节点使用RSVP协议为集聚流预留资源;RSVP使用预计算QoS路由寻找路径。整个模型不仅综合了已有资源管理方案的优点,而且保持了区分服务网络的可扩展性。 相似文献
16.
17.
This paper proposes the Mobility-Aware Resource Reservation Protocol (MARSVP) in which mobility and QoS signaling are performed as a single functional block. The key concept of MARSVP is to convey mobility-specific information (binding updates and their associated acknowledgments) by using newly defined RSVP objects embedded in existing RSVP messages. An appealing feature of MARSVP is that it adheres to the current RSVP standard (RFC 2205) and thus requires minimal changes to end nodes without affecting any of the conventional RSVP routers in between. The proposed mechanism is evaluated using a simulation model for application-level performance and an analytical model for network-level signaling cost. Simulation results indicate a 27.9% improvement in QoS interruption when using Mobile IPv6 (MIPv6), 12.5% when using Hierarchical Mobile IPv6 (HMIPv6), and no improvement when using Fast Handovers for MIPv6 (FMIPv6). On the network-level, signaling cost savings of 9.4% and 11.9% are achieved for MIPv6 and HMIPv6, respectively, while FMIPv6 achieves savings of 17.9% when using Voice-over-IP traffic and 26.7% for Video-over-IP traffic. The results of the conducted studies indicate MARSVP’s superiority to conventional RSVP when deployed over wireless networks. 相似文献
18.
Mauthe Andreas Garcia Francisco Hutchison David Yeadon Nicholas 《Multimedia Tools and Applications》2001,13(3):285-306
Multimedia group applications often operate in an environment where the various participants are located on systems and communication links with different capabilities. Mechanisms are required that ensure full-quality media for high-performance workstations but lower-quality media for playout at low-end systems. QoS filters have been proposed as a way to adapt QoS to the user specified level by changing the structure of a media stream in a well defined way. Resource reservation and QoS filter instantiation should be closely integrated since both represent one particular aspect of the provision of individualistic QoS for heterogeneous users in multipeer communications. The Internet reservation protocol RSVP is receiver oriented and allows each receiver to specify its resource requirements. However, no actual mechanisms are defined that adapt the data stream to the receiver specified QoS requirements.In this paper we present an enhanced version of RSVP (called RSVP++) that integrates resource reservation and QoS filter control. In order to achieve this integration we extend the RSVP functional model and define a new QoS service class. RSVP++ can coexist with common RSVP systems, thus, openness and interoperability of the system are ensured. 相似文献
19.
SIP(Session Initiatioan Protocol)协议是由IETF工作组于1997年7月提出的,是应用层的控制协议,能建立、调整和终止多媒体的呼叫和会话。SIP协议是基于文本方式的,即以明文方式传输。SIP消息包括请求消息、应答消息。SIP协议侧重于将IP电话作为因特网上的一个应用,并且也采用RTP作为媒体传输的协议。本文在SIP通信过程中,采用面向连接的TCP来传输SIP的交互信令,采用面向无连接的UDP协议进行实时音频流传输。本设计是在Linux操作系统下,用套接字(socket)来实现的。设计实现了SIP协议的整个通信过程。最后,提出了进一步开发的设想。 相似文献
20.
层次化移动IPv6环境中的QoS机制 总被引:2,自引:0,他引:2
本文针对层次化移动IPv6的网络提出了一种QoS信令,为移动节点提供服务质量的保障。在分析了RSVP信令的特点及其由于对多播的支持而增加的复杂性的基础上,设计了一个简化的RSVP信令,然后把此RSVP信令和层次化的移动协议相结合提出了一个综合的QoS切换方案,并在层次化的移动环境下,对此QoS信令和其它几种QoS机制在资源预留时间和信令负荷方面进行了性能比较。 相似文献