QoS enhancement for adaptive streaming services over WCDMA

This paper presents a new method to adapt the quality-of-service (QoS) in a wideband code-division multiple-access (WCDMA) system, called radio network feedback (RNF). The concept of RNF is in general applicable to all the services requiring a minimum quality (i.e., non best effort) and in this paper, the focus is on streaming. In this context, RNF makes it possible for a streaming server to adapt its source bit rate to a WCDMA radio link, whose bandwidth may vary in time due, for example, to decongestion/congestion situations over the air interface or to handover. This is very beneficial for the end user as it allows to increase the bandwidth (i.e., the quality) when possible and to decrease it (instead of just dropping the service) when needed. RNF was compared with Client-based adaptation solutions. Simulation results show that RNF is fast and accurate and performs better than Client-based adaptation. For example, rebuffering occurs only with Client-based method. Moreover, with RNF the up-switch is performed only when needed, whereas the up-switch performed by means of the Client-based method is often erroneous and may annoy the end user.     

有线电视网络QoS体系

有线电视网络的业务多样性对QoS障提出了要求。本文提出了有线电视网络的QoS体系框架,并对相关的技术进行了介绍,包括HMS、DOCSIS、DQoS、IQoS等。     

A QoS index for IP services to effectively support usage-based charging

The goal of this letter is to present a model to compute a quality-of-service (QoS) index to characterize IP services. Then, we show how such a score may be used in a clear and flexible way for defining advanced usage-based tariff criteria to charge QoS guaranteed network services to address the dynamics of the expected future telecommunications scenario.     

一种支持HFC网中QoS业务的调度方法

为了在HFC中支持不同QoS的业务,必须仔细研究CMTS的上行业务调度算法。但是在当前最重要的标准 MCNS DOCSIS1.1中,没有规定任何针对 QoS设计的调度算法,而很多文献都是以改进的先到先服务(FCFS)为基础讨论的。该文提出了一种可支持 QoS的调度算法,通过将业务分类,按照不同类型业务的带宽占用动态分配业务的优先级,同时还考虑了回带(piggyback)对网络吞吐量的影响,给出了仿真结果,并针对典型的时延敏感业务IP Telephony提出了改善网络通道利用率的方法。     

QoS and multipoint support for multimedia applications over the ATMABR service

Multimedia applications with stringent delay requirements are usually supported by the constant bit rate (CBR) or real-time variable bit rate (rt-VBR) service categories of ATM. This article shows that the available bit rate (ABR) service, which was originally designed for data, can also support multimedia applications under certain circumstances. Issues related to the design of proper ABR traffic management algorithms for such support are presented     

有线电视数据网服务质量监测方案研究

结合有线电视数据网在运维故障定位难度大、运维工作量大等问题,分析了现有监测技术的特点和适用性,提出了一种基于终端用户视角的数据网服务质量监测技术方案,阐述了数据网服务质量监测系统的工作方式、部署方式和功能模块构成.     

Context aware adaptive fuzzy based QoS routing scheme for streaming services over MANETs

The need for an adaptive with support for context service aware Quality of Service routing scheme is always a major research challenge. The complexities of Mobile Ad hoc Networks are well surveyed, but traditional routing protocols do not focus on the context aware nature of services, which is highly required for dynamic change in service requirements. Context Aware Adaptive Fuzzy (COAAF) is a ‘context aware’ protocol, which is adaptive for variable services and network traffic intensity. The behaviour of streaming services is found to be highly variable; hence, fuzzy approach is adopted. COAAF is simulated over NS-2 and its performance analyzed in comparison with AODV, DYMO and GPSR routing schemes.     

广电城域网服务质量技术分析与设计

首先对各种QoS技术进行分析，然后根据广电城域网业务结构特点，对基于GMPLS和IPv6的区分与综合服务的QoS系统进行了研究，并进行了系统的顶层设计。     

An adaptive cross-layer scheduler for improved QoS support of multiclass data services on wireless systems

With the rapid growth of the Internet and other Internet protocol-related applications, wireless systems have shifted toward supporting a wider variety of data services. This has placed an enormous strain on the already tight capacity of wireless systems. Many improvements have been made at the link layer in second- and third-generation wireless systems. However, further improvements in packet data admission, scheduling, and policing are necessary to maximize capacity and user satisfaction. Of the three, efficient scheduling has the greatest impact on increased system capacity. In addition, proper scheduling can greatly improve user satisfaction. We introduce an adaptive cross-layer packet scheduler, which outperforms popular packet schedulers with respect to both packet delay and user throughput.     

IP/ATM integrated services over broadband access coppertechnologies

A rich set of broadband access copper technologies is available in the market today, and more are coming out of the laboratories, rapidly moving to standardization. The most likely future scenario will be one where many different technologies coexist. This multi-access-technology paradigm poses an interesting internetworking problem where interoperability and capability to support today's and future user services play a major role in the design of a network architecture. This article begins with an overview of current and new xDSL access technologies to continue describing an access network design that harmonizes the interconnection between PON, xDSL, and native ATM transport technologies. The use of ATM technology for the interface to the broadband access and transport networks is then presented and justified. The article continues studying the protocol architectures proposed for access to network service providers, considered a driver application for broadband access deployment. Finally, different protocol architectures that can provide integrated services support at the user equipment are analyzed     

QoS aware traffic grooming and integrated routing on IP over WDM networks

In this article, we consider traffic grooming and integrated routing in IP over WDM networks. The challenges of this problem come from jointly considering traffic grooming, IP routing, and lightpath routing and wavelength assignment (RWA). Due to the high bandwidth of optical fiber, there exists a mismatch between the capacity needed by an IP flow and that provided by a single lightpath. Traffic grooming is therefore used to increase the network utilization by aggregating multiple IP flows in a single lightpath. However, traffic grooming incurs additional delays that might violate Quality-of-Service (QoS) requirements of IP users. In this work, the tradeoff between traffic grooming and IP QoS routing is well-formulated as a mixed integer and linear optimization problem, in which the revenue from successfully provisioning IP paths is to be maximized. Problem constraints include IP QoS, routing, optical RWA, and the WDM network capacity. We propose a novel Lagrangean relaxation (LGR) algorithm to perform constraint relaxation and derive a set of subproblems. The Lagrangean multipliers are used in the proposed algorithm to obtain a solution in consideration of grooming advantage and resource constraints simultaneously. Through numerical experiments and comparisons between the proposed algorithm and a two-phase approach, LGR outperforms the two-phase approach under all experimental cases. In particular, the improvement ratio becomes even more significant when the ratio of IP flow to the wavelength capacity is smaller.     

Design and implementation for integrated services orchestration bus using SCA over heterogeneous networks

As the telecom and IT industries converge, pressure is mounting for convergence of service across the two domains, and future integrated services in the telecom domain are subject to specific requirements such as support for end-to-end communication sessions and mechanisms for service interaction across technological borders including telecom, enterprise, and Internet services. This paper provides an integrated services orchestration bus to handle the interoperation and compositions of services from the different domain and focus on the components lifecycle management, normalized message routing, normalized message parsing and mapping, events serialization processing, JNDI register management, and deploy unit. The multimedia conferencing-use case scenario is illustrated, and also the performance is measured and analyzed. Finally, we give the conclusions and future work.     

以人为本努力提高有线电视用户服务质量

本文介绍国家广电总局已颁布的广电行业第一项用户服务质量标准GY/T204-2004《有线电视用户服务规范》标准的编制思路和主要内容,并提出具体实施建议和思考意见。     

Aggregation methods for integrated services

Reservation aggregation provides scalability to the IETF Integrated Services (IntServ) by reducing the high number of states stored at internal routers and the number of signaling messages processed at these routers. However, in the case of frequent joining and leaving of individual flows, the latter benefit will be lost due to frequent adjustment of aggregation size. In this paper, to reduce aggregation adjustment frequency, we focus on investigating two critical parameters: aggregation size and the lower threshold. We propose two policies to find out the optimal values of these criteria. One policy called Two Bounded operating Policy (TBP) is parameter‐based policy and the other called Resource request Variance Policy (RVP) is measure‐based policy. The calculation of these optimal values considers three costs: underutilization cost, signaling cost and holding cost. In our evaluation study, we compare the proposed two policies with two others, Temporal Operating Policy (TOP) and Cardinal Operating Policy (COP). This study shows that our mechanisms outperform the previous propositions in terms of cost and blocking ratio. Copyright © 2011 John Wiley & Sons, Ltd.     

有线电视网电视会议系统

本文叙述了一套适合于有线电视 HFC网的电视会议系统。系统从充分利用有线电视网现有的资源出发进行开发 ,采用模拟 /数字混合传输方式进行信息传输。系统可实现多级MCU级联 ,并具有网管、多会议管理和多个主会场等能力。     

VOD在有线电视网的实现

从视频点播系统的结构及组成和在有线电视网络中VOD系统的结构模式与应用两个方面，详细地阐述了如何利用有线电视网络实现视频点播，主要从以下3个方面介绍关于视频点播系统VOD技术：①视频点播VOD的技术原理；②视频点播系统的结构及组成；③有线电视视频点播系统的结构模式与应用。     

基于光纤CATV网的会议电视系统

武进市地处长江三角洲的苏、锡、常经济带,经济发达,风光诱人。全市已正式开通了连接30个乡镇的会议电视系统。第一次会议在广电中心主会场召开,全市30个乡镇的分会场同时展映了市长毛伟明的讲话和主席台成员的风采。30个分会场的人员情况,一览尽收于主会场的电视屏幕墙,主持人的点名、查询、分会场的互答,尤如近在咫尺之间。会议电视声像并茂,使人有身临其境、形象直观的感受,的确是一种跨越时空而又节省开支的理想会议形式。     

Extension of Classical IP over ATM to support QoS at the application level

After the introduction of the basic concepts of Classical IP over ATM (CLIP), this paper presents an extension to this standard as well as a full analysis of the technical viability of the extension proposal. One of the major drawbacks of CLIP is the co-existence of IP and ATM without Quality of Service (QoS) support. By extending the functionality of CLIP and redefining the mapping of IP and ATM addresses, QoS can be brought to IP-based applications without requiring any specific definition or implementation changes at the IP layer or above. QACLIP (QoS for Applications using CLIP), the newly defined extension, allows applications to request specific QoS for their data transfer use. This revised version was published online in August 2006 with corrections to the Cover Date.     

Distributed Switching for Data Transmission over Two-Way CATV

Most of tile present approaches to two-way interactive CATV focus on the centralized approach, in which all traffic must travel to the CATV head end. In this paper, we present a distributed approach, in which intelligent store-and-forward packet switches are to be installed at various locations on the cable. The analysis emphasizes three main criteria: the maximum traffic flow on the cable, the throughput of each switch, and the average message delay. Two possible schemes are compared. In one, the switches appear on the main trunk only. In the second, switches are used at branch locations as well.     

Self-adaptive transmission scheme of integrated services over an IEEE 802.11 WLAN

A novel self-adaptive transmission scheme to support integrated data and voice transmission over an IEEE 802.11 WLAN is proposed. The simulation results show that the scheme can improve the data traffic performance and decrease efficiently the voice traffic delay jitter, and then increase the WLAN capacity. It is easy to realise as no change in the MAC protocol is required.