Deployment of IP multimedia streaming services in third-generation mobile networks

In this article, an end-to-end quality of service framework for streaming services in 3G mobile networks is considered. Under this scenario, the interaction between UMTS and IETF's protocols and mechanisms for a streaming session is analyzed. By signaling flowcharts, it is shown that both groups of protocols and mechanisms can co-operate to provide seamless end-to-end real-time services. Specifically, the article proposes to make the IP multimedia subsystem aware of the real time streaming protocol, in order to extend its control from SIP to RTSP-based services, such as multimedia streaming services. Supported by this proposed framework, provisioning of audio streaming services over 3G mobile networks is also outlined.     

QoS-enabled broadband mobile access to wireline networks

Third-generation wireless systems, known as IMT-2000 within the ITU, offer opportunities to support a wide range of multimedia services. Packet data services will play a major role in these new multimedia services. A key component of packetized data services is to ensure end-to-end QoS requirements through efficient management of the network's resources. We present an overview of radio resource scheduling schemes including architecture, radio interface protocol, and interactions in a wideband CDMA environment. We then present an example of the QoS architecture followed by a discussion on end-to-end provisioning and interworking from wireless to fixed networks     

Enabling transparent lambda services between metro and core networks

Transparent end-to-end lambda services represent a highly desirable technology for both enabling bandwidth-greedy applications and reducing the telecommunication network capital and operational expenditures. However current network architectures, organized over different segments based on different technologies, are not tailored to efficiently provide end-to-end lambda services. This paper proposes a solution allowing optical bypass of the edge between the metro and the core segments. The proposed solution enables end-users belonging to different metro networks to directly communicate by establishing a lambda service traversing a common GMPLS-based core network. This paper details the lambda service setup mechanism, integrating access, metro and core segments, and the architecture of the metro-core edge node. Simulation results show that the proposed optical bypass of the metro-core edge is capable of providing high bandwidth end-to-end lambda services and reduces the utilization of expensive and power-hungry OEO interfaces without impacting network throughput.     

Integrated Services on High Altitude Platform: Receiver Driven Smart Selection of HAP-Geo Satellite Wireless Access Segment and Performance Evaluation

A renewed interest in the development of high-altitude platforms (HAPs), which are stratospheric aircraft or airship carrying payloads tailored for a wide range of applications in telecommunications and remote sensing, is becoming progressively widespread. HAPs offer a reduced propagation delay and they are especially suitable for interactive multimedia services. In this paper, the inter-working between HAP and satellite segments in an integrated QoS architecture has been addressed. A new way to manage integrated services over a new hybrid wireless platform has been proposed. A smart terminal device has been considered in order to perform an intelligent switching on the wireless access segment. The switching criteria applied in the HAP/satellite architecture is based on the available bandwidth and on the admissible data packet end-to-end delay. Performance evaluations of the integrated HAP–satellite platform have been evaluated in terms of bandwidth utilization and number of admitted calls. The simulations show an improvement of admitted calls, reduced data packet end-to-end delay and increased bandwidth utilization.     

WCDMA IP多媒体子系统中基于策略的QoS管理

WCDMA可为用户提供高速的多媒体业务,为了能够更好地提供多媒体业务,3GPP标准化组织自R5版起在分组域上添加了IP多媒体子系统,利用IP多媒体子系统提供端到端的、有QoS保证的、基于IP的多媒体应用服务,其核心部分就是基于策略的QoS控制管理.本文将详细介绍IP多媒体子系统中基于策略的QoS管理体系结构,以及它是如何实现QoS保证的.     

Multimedia communication systems: upper layers in the OSI referencemodel

The structuring, services, and major protocol functions that are required in the upper layers of the OSI reference model in order to support end-to-end multimedia communication, assuming a simple transport service, are examined. It is assumed that variable-bit-rate (VBR) coding techniques will be used in future multimedia systems. Mutual stream synchronization, integral management, and multiparty connections, which appear to be crucial issues in multimedia communication, are addressed. Important implementation and performance issues are discussed     

Implementation of a Communications Channelizer using FPGAs and RNS Arithmetic

The emergence of mobile Internet services has introduced a set of transmission and presentation standards that aim to address multimedia. At the same time, the limited resources of cellular networks and terminals set strict requirements to the bandwidth-limited transmission and presentation. We propose a new abstract model to adapt and represent multimedia in mobile environments to meet these restrictions. The model includes a layered mapping of semantic and physical entities and is combined under the taxonomy of “multimedia adaptation” to optimize an end-to-end mobile service. Our technique is media and presentation format independent and easily absorbs additions. We conclude with an example mobile service that utilizes the proposed techniques.     

UMTS-to-IP QoS mapping for voice and video telephony services

Quality of service mapping between UMTS services and IP transport is crucial for maintaining a suitable end-to-end delay for emerging UMTS multimedia telephony. However, due to incompatibilities in QoS classifications within these two technologies, straightforward mapping is impossible and current proposals within the 3GPP could lead to unpredictable and undesirable behavior for certain services. In this article we focus on two very important UMTS services, voice and video telephony, and establish the QoS issues that exist for these services. We then propose a refined QoS mapping that differentiates between the transmission of voice and video-telephony and a weighted fair queuing scheduler to schedule the transmissions. Through a simulation study, we show the effect on the queuing delays of both traffic types when their WFQ weights vary and then derive an optimal weight that provides the best overall delays for multimedia telephony services.     

Multimedia group synchronization protocols for integrated servicesnetworks

Unlike traditional data traffic, real time multimedia traffic requires synchronization. Temporal relationships among media must be maintained. Yet delay jitter and the absence of a global clock may disrupt these temporal relationships. This paper introduces new group synchronization protocols for real-time, multimedia applications, including teleconference, teleorchestration and multimedia on demand services. The proposed protocols achieve synchronization for all configurations (one-to-one, one-to-many, many-to-one, and many-to-many), and does so without prior knowledge of the end-to-end delay distribution, or the distribution of the clock drift. The only a-priori knowledge the protocols require is an upper bound on the end-to-end delay. The paper concludes with simulation experiments showing that the protocols work effectively in both LAN and WAN environments     

QoS-aware TDMA for end-to-end traffic scheduling in ad hoc networks

The proliferation of low-cost broadband air interfaces has paved the way to the introduction of high-definition multimedia services in mobile and wireless networks. The cost for network resources utilization, when provisioning such services, will play a prominent role in their commercial success, since the more spare resources that can be used, the more cheaply the services can be delivered to the end users. In the context of promoting the role of ad hoc networks as service platforms for high quality multimedia applications, this article first discusses and classifies a set of issues involved in quality of service (QoS) provisioning in ad hoc networks and then presents a congestion-free TDMA algorithm for end-to-end network resources assignment via an optimized mechanism that relies on capacity requests and grants. The article also illustrates a method for invoking this algorithm to achieve efficient end-to-end QoS provisioning and concludes by showing the superiority of the proposed algorithm, as compared to other recently proposed TDMA scheduling algorithms     

一种异构网络中基于聚集流的水平QoS映射方法

保证无线异构网络端到端QoS需求,同时兼容现有网络业务和未来需求,是下一代网络的一个研究热点。QoS映射是保证异构网络端到端QoS的有效方法。该文提出一种基于聚集流的QoS映射方法(QoS Mapping Technology based on Flow Aggregate, QMT-FA),该方法在现有物理网络上建立虚拟的流处理层,在流处理层,原网络中的QoS参数被映射执行器透明封装,映射执行器根据网络情况决定是原样转发还是解聚集。通过建立基于高维的聚集流映射空间,屏蔽了多级网络间映射累积误差影响终端网络QoS指标,保证了异构网络端到端QoS;基于聚集流的QoS映射方法具有较好的可扩展性和伸缩性,能应用于现有的各种异构网络系统和应用业务。最后,通过数值和仿真分析验证了该方法的有效性。     

A CORBA-based quality of service management framework fordistributed multimedia services and applications

For distributed multimedia services, it is essential that quality of service be guaranteed system-wide, including end systems, communication systems, and networks. Although many researchers have addressed issues of QoS management, little attention has so far been paid to the QoS management services in distributed multimedia services and applications. To address this deficiency, we have designed a layered model for end-to-end QoS management called the QoS management framework. Our framework, which is CORBA-based, includes a generic QoS MIB for the QoS parameterization of various multimedia services and the services needed to perform various QoS functions. A key component of this framework is the QoS management service object (QMSO), which orchestrates resources at endpoints, coordinating resource management across layer boundaries. Services such as translation, monitoring, admission, and negotiation are provided by the QMSO. To validate this concept, we have developed a QoS management system for managing and controlling the QoS of a distributed multimedia system called MAESTRO. The QoS management system has been implemented through CORBA objects and provides an interface to multimedia applications, which can be dynamic negotiation and renegotiation of QoS by users. Some performance results in QoS negotiation and renegotiation are also presented     

A comparison of competing broadband in-home technologies

Connecting each house to a broadband access network represents an unprecedented opportunity to offer added-value services and broadband Internet access to residential users and expand the customer base beyond the corporate environment. Home networks, however, may be the last barrier to end-to-end multimedia service provisioning. Although a large number of houses have PCs, modems or multimedia network-enabled appliances, the majority are not equipped to support their interconnection, and most consumers are unwilling or cannot afford large-scale home rewiring. This paper reviews the available home-networking technologies and provides a comparison of the competing broadband in-home technologies. The focus is on technologies that do not require rewiring the home, either reusing the existing wiring or using wireless technology. The paper also discusses the residential gateway (RG) initiative, which provides a single point of convergence between the in-home and the access networks     

RSVP and integrated services in the Internet: a tutorial

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     

QoS guarantees for multimedia services on a TDMA-based satellitenetwork

This article describes a proposed network architecture for both the ground and space segments of a satellite network supporting multimedia services with quality of service (QoS) guarantees. The space segment proposal is geared toward a TDMA-based satellite network comprising many nongeostationary satellites, while the ground segment proposal does not put any restriction an the satellite network. The ground segment proposal is based on the new ATM adaptation layer 2 (AAL2) which we consider to have a major role to play in offering an efficient way to provide multimedia services over ATM networks. Indeed, it allows easy encapsulation of the complete set of media component sessions which forms a multimedia transaction into a single ATM virtual channel connection. An additional advantage of AAL2 is that it can run over any arbitrary slotted access system independent of the ATM format (i.e., without transporting the ATM cell headers). This is important for efficient interfacing of the ground and space segments. The space segment proposal aims at providing a robust, easily managed and controlled architecture to guarantee QoS by using a combination of connectionless and connection-oriented techniques. This is achieved by: defining a fixed logical network architecture (i.e., independent of the motion of the satellites); limiting the functionality of the switches in the sky; and using adequate addressing and routing procedures     

QoS issues in the converged 3G wireless and wired networks

The Internet evolution delineated through the last years has urged the wireless network community to support the deployment of IP multimedia services with guaranteed quality of service (QoS) in 3G wireless networks. This article copes with the interoperability between 3G wireless networks and wired next-generation IP networks, for the provision of services with an a priori known quality level over both environments. More specifically, the UMTS architecture as well as a prototypical implementation of the next-generation Internet based on DiffServ are considered. The article focuses on the mapping among the traffic classes of the two networks at the point where the networks converge, and discusses the requirements and possible solutions for their proper interworking at the signaling and user levels. Simulations prove that proper mapping among the traffic classes of each world is necessary in order to achieve the desired end-to-end traffic characteristics.     

Policy-based QoS architecture in the IP multimedia subsystem of UMTS

The third-generation mobile system, or Universal Mobile Telecommunication System, will offer IP-based multimedia applications and services with end-to-end QoS guarantee. The key part providing these services is the policy-based QoS control architecture in the IP multimedia subsystem (IMS). In this tutorial we describe the network entities involved in the policy-based QoS architecture, their interactions to realize guaranteed QoS in the UMTS network, and the communication interfaces employed in the interactions.     

A survey of future broadband multimedia satellite systems, issuesand trends

The demand for advanced information services is growing in terms of both the number of users and the services to be supported. Voice and low-rate data services are insufficient for users in a world where high-speed World Wide Web access is taken for granted. The trend is toward global information networks offering flexible multimedia information services to users on demand, anywhere, anytime. Potential services include video on demand, interactive video, fast Internet access, telemedicine, tele-education, and large file transfer. The need to support bandwidth-intensive multimedia services places new and challenging demands on satellite systems and networks. Flexibility, efficiency, mobility, and the ability to guarantee end-to-end quality of service are at a premium     

Realizing a foundation for programmability of ATM networks with thebinding architecture

A conceptual framework, called the binding model, for the creation, deployment and management of multimedia services on ATM-based broadband networks with end-to-end quality-of-service (QoS) guarantees is presented. The key function of the associated binding architecture is to provide an open programmable environment that facilitates the easy creation of flexible services. We describe the implementation of a prototype binding architecture called xbind as a middleware toolkit for building open programmable ATM networks. Finally, we present our initial experiences with experimenting and deploying xbind over an ATM testbed and highlight some of the lessons learned     

A survey of quality of service in IEEE 802.11 networks

Developed as a simple and cost-effective wireless technology for best effort services, IEEE 802.11 has gained popularity at an unprecedented rate. However, due to the lack of built-in quality of service support, IEEE 802.11 experiences serious challenges in meeting the demands of multimedia services and applications. This article surveys 802.11 QoS schemes, including service differentiation in the MAC layer, admission control and bandwidth reservation in MAC and higher layers, and link adaptation in the physical layer, designed to meet these challenges by providing the necessary enhancements for the required QoS. Furthermore, the article addresses issues that arise when end-to-end QoS has to be guaranteed in today's pervasive heterogeneous wired-cum-wireless networks. Among these challenges, protocol interoperability, multihop scheduling, full mobility support, and seamless vertical handoff among multiple mobile/wireless interfaces are specifically addressed.