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1.
While the Internet keeps its penetration into every facet of life and every corner of the globe, two things stand out. One is the hunger for high quality of services to convey audio and video data. The other is the desire for ubiquitous connections. Combining the two we have an Internet that is capable of supporting multimedia communications for nomadic users on the move. To have a high quality connection, resource must be allocated along the connection path. The current Internet standard for resource reservation is RSVP (Resource reSerVation Protocol), which is receiver-initiated and allows one-to-one or one-to-many communication to have resource reserved in the path from sender to receiver(s). To support mobile users, the Internet also has the mobile IP standard. Mobile IP allows a mobile host to roam from one subnet to another seamlessly. However, several problems need to be solved before we can support QoS communications for mobile users by applying RSVP to mobile IP. In this paper, we identify four problems related to RSVP over mobile IP. The problems are the resource pre-reservation problem, the RSVP tunneling problem, the common path identification problem, and the mobile proxy problem. We also survey the various solutions proposed by many papers. 相似文献
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RSVP and integrated services in the Internet: a tutorial 总被引:6,自引:0,他引:6
The growing use of multimedia communication applications, with specific bandwidth and real-time delivery requirements has created the need for an integrated services Internet in which traditional best-effort datagram delivery can coexist with additional enhanced quality of service (QoS) delivery classes. Such classes provide data flows with QoS commitments with regard to bandwidth, packet loss, and delay through the reservation of network resources along the data path, which can be done using the Resource Reservation Protocol (RSVP). This article is a tutorial on how RSVP can be used by end applications to ensure that they receive the end-to-end QoS that they require 相似文献
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本文针对Internet传输协议TCP的和式增加积式减少(AIMD)拥塞控制机制不适应多媒体通信,而目前拥塞控制的研究又大多集中在尽量做好(Best-effort)服务上的问题,结合Internet上多媒体通信的特点及其对QoS的要求,提出了一种将多媒体通信服务质量(QoS)控制和基于速率拥塞控制结合起来的拥塞控制的新机制.本文详细地研究了这一机制,并提出了源端多媒体数据流的带宽控制策略、基于动态部分缓存共享(DPBS)的数据包丢失控制方案和接收端计算包丢失率p的方法.最后给出了整个拥塞控制机制的系统结构. 相似文献
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Architecture and experimental results for quality of service in mobile networks using RSVP and CBQ 总被引:3,自引:0,他引:3
Efforts are underway to enhance the Internet with Quality of Service (QoS) capabilities for transporting real‐time data. The
issue of wireless networks and mobile hosts being able to support applications that require QoS has become very significant.
The ReSerVation Protocol (RSVP) provides a signaling mechanism for end‐to‐end QoS negotiation. RSVP has been designed to work
with wired networks. To make RSVP suitable for wireless networks, changes need to be made by: (i) changing the way control
messages are sent, and (ii) introducing wireless/mobile specific QoS parameters that take into account the major features
of wireless networks, namely, high losses, low bandwidth, power constraints and mobility. In this paper, an architecture with
a modified RSVP protocol that helps to provide QoS support for mobile hosts is presented. The modified RSVP protocol has been
implemented in an experimental wireless and mobile testbed to study the feasibility and performance of our approach. Class
Based Queueing (CBQ) which is used as the underlying bandwidth enforcing mechanism is also modified to fit our approach. The
experimental results show that the modified RSVP and CBQ help in satisfying resource requests for mobile hosts, after handoff
occurs. The experiments also show how different power and loss profile mechanisms can be used with our framework. The system
performance using the modified RSVP control mechanism is also studied.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Yi Sun Yucheng Zhang Yilin Song Eryk Dutkiewicz 《Wireless Personal Communications》2011,60(4):769-807
In recent years, with the development of mobile communication technologies and the increase of available wireless transmission
bandwidth, deploying multimedia services in next generation mobile IPv6 networks has become an inevitable trend. RSVP (resource
reservation protocol) proposed by the IETF is designed for hardwired and fixed networks and can not be used in mobile environments.
This paper proposes a protocol, called Fast RSVP, to reserve resources for mobile IPv6. The protocol adopts a cross-layer
design approach where two modules (RSVP module and Mobile IPv6 module) at different layers cooperate with each other. Fast
RSVP divides a handover process with QoS guarantees into two stages: (1) setup of the resource reservation neighbor tunnel
and (2) resource reservation on the optimized route. It can help a mobile node realize fast handover with QoS guarantees as
well as avoid resource wasting by triangular routes, advanced reservations and duplicate reservations. In addition, fast RSVP
reserves “guard channels” for handover sessions, thus greatly reducing the handover session forced termination rate while
maintaining high performance of the network. Based on extensive performance analysis and simulations, Fast RSVP, compared
with existing methods of resource reservation in mobile environments, performs better in terms of packet delay and throughput
during handover, QoS recovery time after handover, resource reservation cost, handover session forced termination rate and
overall session completion rate. 相似文献
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因特网的快速发展,促使各种应用及服务不断涌现.多协议标签交换(MPLS)作为一种非常灵活的载体,不仅可以传输数据,而且可以利用其在资源预留协议(RSVP)、服务质量(QoS)方面的优势提供语音及多媒体等方面的服务.文章首先介绍MPLS两种主流语音传输技术,进而与VoIP的传输性能进行了比较分析,最后探讨了VoMPLS存在的技术问题和VoMPLS将来的应用前景. 相似文献
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The Multimedia Internet Terminal (MInT)\protect\footnotemark[1] is a flexible multimedia tool set that allows the establishment and control of multimedia sessions across the Internet. The system architecture is fully distributed, with no central components. For each participant, a coordinating application manages a set of loosely coupled media and control agents. Using the coordinating application, session members can control the sending and receiving of several audio and video streams, invite other users to the session and negotiate the order in which members are allowed to speak. The different components of MInT are separate processes that are independent from one another, yet can easily communicate with each other using a simple interprocess communication protocol based on local multicast. Individual components can be replaced without affecting the operation of other components. The same media agents can be used in applications ranging from mediaondemand retrieval to Internet telephony and distance learning, simply by using different control tools. To improve the quality of service of the multimedia sessions MInT is enhanced with a suite of QoS control mechanisms including resource reservation based on RSVP, adaptive media control and the ability to send video data in hierarchically layered streams. Thus, the tool set can accommodate a range of capabilities and available network bandwidths in heterogeneous environments. 相似文献
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In principle, the interaction of the resource reservation protocol (RSVP) and ATM should allow the IP level to benefit from some features of the ATM layer. The most interesting one is the native support of end-to-end quality of service provided by ATM. On the other hand, there are issues that must be clarified to define correct interworking: for example, the possible overlapping between the mechanisms used in the IP and ATM levels to support QoS, or the needed IP/ATM address resolution mechanism. This article proposes a solution to exploit ATM shortcut VCs supporting QoS in the Internet integrated services model. A straightforward enrichment to the RSVP protocol is defined, which only impacts the devices (hosts and routers) involved in the shortcut procedure. A mechanism for IP/ATM address resolution is provided, avoiding the use of other mechanisms such as NHRP. Special care has been taken to maintain compatibility with “traditional” RSVP hosts and routers 相似文献
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Quality-of-service mechanisms in all-IP wireless access networks 总被引:7,自引:0,他引:7
In this paper, we focus on resource reservation protocol (RSVP)-based quality-of-service (QoS) provisioning schemes under Internet protocol (IP) micromobility. We consider QoS provisioning mechanisms for on-going RSVP flows during handoff. First, the rerouting of RSVP branch path at a crossover router (CR) at every handoff event can minimize resource reservation delays and signaling overheads, and in turn the handoff service degradation can be minimized. We show that RSVP branch path rerouting scheme could give a good tradeoff between the resource reservation cost and the link usage. Second, the new RSVP reservation can be made along the branch path toward the CR via a new base station in advance, while the existing reservation path is maintained, and in turn the on-going flow can be kept with the guaranteed QoS. We also show that seamless switching of RSVP branch path could provide the QoS guarantee by adaptively adjusting the pilot signal threshold values. Third, during RSVP resource reservation over wireless link, dynamic resource allocation scheme is used to give a statistical guarantee on the handoff success of on-going flows. We finally obtain the forced termination probability of guaranteed service flows, the average system time of best effort flows by using a transition rate matrix approach. 相似文献
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Part I (ibid., July-Oct. 1997) surveyed the evolution of Internet protocols and applications and described the Internet protocol IPv6 in detail. This part discusses new developments at the upper layers that support real-time Internet multimedia, such as audio and video conferencing and shared whiteboard applications. Application-level framing (ALF), proposed in 1990 for protocol and application design, now forms the basis for many new Internet protocols and applications, including Real-time Transport Protocol (RTP) and Mbone multimedia applications. RTP supports real-time applications that adapt to changing network situations to maintain the quality of service (QoS). The Resource Reservation Protocol (RSVP) provides new Internet services with higher quality than best-effort by means of resource reservations 相似文献
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LUO Qiang-qiang ZHU Zhi-xiang HUANG Ting-xueXi''''an Institute of Posts & Telecommsunication Xi''''an China 《中国邮电高校学报(英文版)》2005,12(3)
1 Motivation Nowadays , the QoS provided by the wideband IPnetwork starts at an edge-router and ends at anotheredge-router .Therefore ,the trunk QoSisfinished,suchas RSVP[1]and DiffServ[2].In order to complete theend-to-end QoS,the mechanism of entrance QoS (thebandwidth controller) is introduced. As Fig.1 shows ,if the bandwidth controller circledby the dashed frame is not used,the Ethernet is con-nected with the router directly through 100 Mbit/sbandwidth. Then this router is connect… 相似文献
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Two phase load balanced routing using OSPF 总被引:1,自引:0,他引:1
Antic M. Maksic N. Knezevic P. Smiljanic A. 《Selected Areas in Communications, IEEE Journal on》2010,28(1):51-59
The Internet traffic is growing, and its nature changes because of new applications. Multimedia applications require bandwidth reservations that were not needed initially when the file transfers dominated the Internet. P2P applications are making traffic patterns impossible to predict, and the traffic loads generated at nodes need to be routed regardless of the traffic pattern. When the guaranteed node traffic loads are known, bandwidth reservations can be made simple as will be explained in the paper. The shortest path routing (SPR) protocols used on the Internet today do not maximize the guaranteed node traffic loads, and do not provide scalable and fast bandwidth reservations. Load balancing can improve the network throughput for arbitrary traffic pattern. In this paper we analyze and implement a routing protocol that is based on load balancing and a commonly used shortest path routing protocol, and is, consequently, termed as LB-SPR. LB-SPR is optimized for an arbitrary traffic pattern, i.e. it does not assume a particular traffic matrix. Optimization assumes only the weights assigned to the network nodes according to their estimated demands. It will be shown that the optimized routing achieves the throughputs which are significantly higher than those provided by the currently used SPR protocols, such as OSPF or RIP. Importantly, LB-SPR calculates the guaranteed traffic loads and so allows fast autonomic bandwidth reservations which are the key for the successful support of triple-play applications, including video and audio applications that require high QoS. An actual modification of the TCP/IP stack that includes LBSPR is also described. Using the signaling mechanisms of the OSPF protocol, the information needed to perform the routing optimization is automatically distributed among the network nodes whenever the network topology changes. The LB-SPR implementation is validated on a sample network using a popular virtualization tool - Xen. 相似文献
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Video Streaming with Network Coding 总被引:2,自引:0,他引:2
Recent years have witnessed an explosive growth in multimedia streaming applications over the Internet. Notably, Content Delivery
Networks (CDN) and Peer-to-Peer (P2P) networks have emerged as two effective paradigms for delivering multimedia contents
over the Internet. One salient feature shared between these two networks is the inherent support for path diversity streaming
where a receiver receives multiple streams simultaneously on different network paths as a result of having multiple senders.
In this paper, we propose a network coding framework for efficient video streaming in CDNs and P2P networks in which, multiple servers/peers are employed to simultaneously
stream a video to a single receiver. We show that network coding techniques can (a) eliminate the need for tight synchronization
between the senders, (b) be integrated easily with TCP, and (c) reduce server’s storage in CDN settings. Importantly, we propose
the Hierarchical Network Coding (HNC) technique to be used with scalable video bit stream to combat bandwidth fluctuation
on the Internet. Simulations demonstrate that under certain scenarios, our proposed network coding techniques can result in
bandwidth saving up to 60% over the traditional schemes. 相似文献
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In this paper, we describe a mechanism for adaptive transmission of multimedia data, which is based on real‐time protocols. The proposed mechanism can be used for unicast or multicast transmission of multimedia data over heterogeneous networks, like the Internet, and has the capability to adapt the transmission of the multimedia data to network changes. In addition, the implemented mechanism uses an inter‐receiver fairness function in order to treat the group of clients with fairness during the multicast transmission in a heterogeneous environment. The proposed mechanism uses a ‘friendly’ to the network users congestion control policy to control the transmission of the multimedia data. We implement a prototype application based on the proposed mechanism and we evaluate the proposed mechanism both in unicast and multicast transmission through a number of experiment and a number of simulations in order to examine its fairness to a group of clients and its behaviour against transport protocols (TCP) and UDP data streams. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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CORBA is an object-oriented middleware defined by the OMG. It is designed to support the development of distributed applications by separating interfaces from implementations. Unfortunately, CORBA does not consider QoS requirements inherent to new applications such as teleconferencing and telecommunication services. The Resource reSerVation Protocol (RSVP) is an IETF protocol that allows real-time applications to reserve necessary resources at routers along the transmission paths, so the requested bandwidth can be available when transmission actually takes place. In this paper, we discuss the use of Notification Service and RSVP to provide end-to-end QoS to applications supported by CORBA architecture. 相似文献
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Internet越来越成为人们信息交流的重要媒体,但是传统Internet基于IP协议的尽力(best-efort)传送模型,满足不了实时业务的QoS要求。根据当前技术的最新进展,介绍基于RSVP协议的资源预留机制,分析在Internet上采用RSVP协议实现有QoS保障的业务时存在的问题和解决对策。 相似文献