Multimedia Streaming Services Research Articles

Adaptive Multimedia Flow Splitting over WiMAX and WiFi Links

To meet the bandwidth requirements of multimedia services, multipath transmission is a promising solution. In this paper, we consider multi-access networks, where WiMAX and WiFi links are set up at the same time. Multipath transmission suffers from the intrinsic problem of out-of-order packet delivery. This has an adverse impact on TCP and even UDP-based delay sensitive applications. However, multimedia streaming services allow some tolerance to transmission delay. Motivated by this observation, we investigate how to split multimedia flows over heterogeneous links. Wireless link capacity varies widely over time due to dynamic radio conditions. The capacity variations should be promptly reflected in traffic splitting in order to accomplish an equal load-balance. A practical prototype system has been implemented. We have performed extensive measurements from a prototype system. Through practical experimental results, we could verify two major research goals. One is that multimedia splitting can improve the overall network performance (e. g., the permitted multimedia sessions or the aggregated bandwidth) while still keeping an acceptable media quality. The other is an adaptation capability to varying link quality. It has been widely investigated under various radio conditions and different monitoring intervals. It is shown that the adaptive technique is effective under dynamic radio environments.

Proxy Server Caching Technique of Distributed Chunk File for Multimedia Streaming Service

Proxy Server Caching Technique of Distributed Chunk File for Multimedia Streaming Service

Proposal of Wireless Traffic Control Schemes for Wireless LANs

This paper proposes two traffic control schemes to support the communication quality of multimedia streaming services such as VoIP and audio/video over IEEE 802.11 wireless LAN systems. The main features of the proposed scheme are bandwidth control for each flow of the multimedia streaming service and load balancing between access points (APs) of the wireless LAN by using information of data link, network and transport layers. The proposed schemes are implemented on a Linux machine which is called the wireless traffic controller (WTC). The WTC connects a high capacity backbone network and an access network to which the APs are attached. We evaluated the performance of the proposed WTC and confirmed that the communication quality of the multimedia streaming would be greatly improved by using this technique.

Multicast Broadcast Services Support in OFDMA-Based WiMAX Systems [Advances in Mobile Multimedia

Multimedia stream service provided by broadband wireless networks has emerged as an important technology and has attracted much attention. An all-IP network architecture with reliable high-throughput air interface makes orthogonal frequency division multiplexing access (OFDMA)-based mobile worldwide interoperability for microwave access (mobile WiMAX) a viable technology for wireless multimedia services, such as voice over IP (VoIP), mobile TV, and so on. One of the main features in a WiMAX MAC layer is that it can provide'differentiated services among different traffic categories with individual QoS requirements. In this article, we first give an overview of the key aspects of WiMAX and describe multimedia broadcast multicast service (MBMS) architecture of the 3GPP. Then, we propose a multicast and broadcast service (MBS) architecture for WiMAX that is based on MBMS. Moreover, we enhance the MBS architecture for mobile WiMAX to overcome the shortcoming of limited video broadcast performance over the baseline MBS model. We also give examples to demonstrate that the proposed architecture can support better mobility and offer higher power efficiency.

Design of Home Network Gateway for Real-Time A/V Streaming between IEEE1394 and Ethernet

For practical multimedia streaming services in home networks, seamless binding between two stream formats (digital video (DV) and MPEG-4), on two heterogeneous protocols (IEEE 1394 and Ethernet), is required. IEEE 1394 is the best way for the real-time transmission of high bandwidth audio/video (A/V) content inside a home, and Ethernet provides a connection to anywhere, not only in homes, but also outside by using wired or wireless mobile solutions, however, because of differences between the two stream solutions (DV-IEEE 1394 and MPEG-4-Ethernet), an appropriate device or function is needed between the two parts. In this paper, the software and hardware architecture of a media gateway are suggested in order to solve the problems. First, hardware architecture was designed to support transcoding functions between DV and MPEG-4 in real-time. It also solves resource limitations between two protocols and related devices such as bandwidth and quality factors. Suggested software architecture coordinates the heterogeneity of transaction management and addressing mechanisms between two protocols. Based on the design requirements of the proposed system, we implemented a prototype media gateway based on the proposed architecture and the performance was evaluates being successful.

Considering User Behavior and Multiple QoS Supports in Multimedia Streaming Caching

With the prevalence of video-on-demand (VOD) services as well as the diffusion of various multimedia devices, caching in a multimedia streaming server is becoming increasingly important. However, due to some peculiar characteristics of multimedia objects and user activities in streaming services, design of an efficient caching system becomes a more challenging problem compared to the traditional caching systems. This paper discusses some important issues that are of interest in the domain of multimedia streaming caching and presents a new cache management scheme for multimedia streaming servers. Our new scheme considers different streaming rates of multimedia objects as well as the inter-arrival time between two consecutive requests on an identical object. It also considers user activities in requesting and playing multimedia contents. Trace-driven simulations with real world VOD traces show that the proposed scheme improves the performance of multimedia streaming systems significantly.

3D Model Streaming Based on JPEG 2000

For PC and even mobile device, video and image streaming technologies, such as H.264 and JPEG/JPEG 2000, are already mature. However, the streaming technology for 3D model or so-called mesh data is still far from practical use. Therefore, in this paper, we propose a mesh streaming method based on JPEG 2000 standard and integrate it into an existed multimedia streaming server, so that our mesh streaming method can directly benefit from current image and video streaming technologies. In this method, the mesh data of a 3D model is first converted into a JPEG 2000 image, and then based on the JPEG 2000 streaming technique, the mesh data can then be transmitted over the Internet as a mesh streaming. Furthermore, we also extend this mesh streaming method for deforming meshes as the extension from a JPEG 2000 image to a motion JPEG 2000 video, so that our mesh streaming method is not only for transmitting a static 3D model but also a 3D animation model. To increase the usability of our method, the mesh stream can also be inserted into a X3D scene as an extension node of X3D. Moreover, since this method is based on the JPEG 2000 standard, our system is much suitable to be integrated into any existed client-server or peer-to-peer multimedia streaming system.

Impact of Background Traffic on Speech Quality in VoWLAN

This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.

Bandwidth Estimation in Wireless Lans for Multimedia Streaming Services

The popularity of multimedia streaming services via wireless networks presents major challenges in the management of network bandwidth. One challenge is to quickly and precisely estimate the available bandwidth for the decision of streaming rates of layered and scalable multimedia services. Previous studies based on wired networks are too burdensome to be applied to multimedia applications in wireless networks. In this paper, a new method, IdleGap, is suggested to estimate the available bandwidth of a wireless LAN based on the information from a low layer in the protocol stack. We use a network simulation tool, NS-2, to evaluate our new method with various ranges of cross-traffic and observation times. Our simulation results show that IdleGap accurately estimates the available bandwidth for all ranges of cross-traffic (100 Kbps ∼ 1 Mbps) with a very short observation time of 10 seconds.

실시간 멀티미디어 스트리밍 서비스를 위한 Time-triggered Message-triggered Object 기반의 프레임워크 및 동기화 메커니즘

본 논문에서는 실시간 객체모델인 Time-triggered Message-triggered Object (TMO)를 사용하여 분산 실시간 멀티미디어 스트리밍 서비스를 효과적으로 개발 할 수 있는 새로운 소프트웨어 프레임워크와 스트림 동기화 메커니즘을 소개한다. 본 프레임워크의 목적은 개발자로 하여금 복잡한 실시간 멀티미디어 스트리밍 서비스를 쉽게 설계하고 적시 스트리밍 기능들을 제공하는데 있다. 이를 위해서 본 프레임워크는 Multimedia Streaming TMO, MMStream TMO Support Library 그리고 TMO Support Middleware로 구성된다. 특히, MMStream TMO와 동기화 기법이 제공하는 time-trigger번 특성은 QoS 보장이 어려운 통신 채널과 시스템 환경에서 불규칙한 미디어 데이터 전달 및 처리하는 역할을 실시간으로 수행한다. 결론적으로 본 논문에서 제시한 프레임워크의 적시 서비스 능력은 향후 실시간 멀티미디어 스트리밍 서비스 개발에 기여할 것으로 기대된다. In this paper, we present a new framework and stream synchronization mechanism to effectively support developing real-time multimedia streaming services by using a real-time object model named TMO (Time-triggered Message-triggered Object). The purpose of the framework is twofold. Firstly, the framework helps developers to design complex distributed real-time multimedia streaming services. Secondly, it supports timely streaming facilities. In order to achieve these goals, our framework is consist of Multimedia Streaming TMO, MMStreaming TMO Support Library and TMO Support Middleware. The time-triggered spontaneous feature of the MMStream TMO and a global-time based synchronization scheme is used as a regulator against the irregular deliveries and processing of media units caused by QoS non-guaranteed systems and communication channels. In conclusion, timely service capability of our framework is expected to contributed to overall enhancement of the real-time multimedia streaming.

Tentative Accommodating and Congestion Confirming Strategy--A Novel Admission Control Strategy for Packet Switching Networks--

Admission control is becoming an essential technique for IP networks to provide full-fledged multimedia streaming services. Although signaling-based schemes are utilized to achieve this, these are difficult to deploy and can hardly achieve strict admission control taking the properties of packet arrival into consideration. In this paper, we propose a novel admission control strategy called the Tentative Accommodating and Congestion Confirming Strategy (TACCS). The main idea is to accommodate incoming flows tentatively and confirm congestion after a certain period. Since tentative accommodating enables us to generate the same situation as where incoming flows have been accommodated, TACCS makes it possible to control admission considering the properties of packet arrival after they have been accommodated, without collecting resource information in advance. From the results of mathematical analysis, we confirmed that TACCS enabled a domain to control admission without a centralized management agent and we provided guidelines for configuring parameters of TACCS.

Scalable MPEG-4 streaming over the IPv6 mobile network environment

With the advancement of mobile technologies, more and more mobile devices are designed for multimedia streaming services. A server-proxy-client network architecture is usually adopted to improve the quality of multimedia streaming services. However, proxy servers not only cache data for reducing the waiting time, but also tackle the user mobility in the IPv6 mobile networks. We assume that a mobile client is moving from subnet to subnet. If the mobile client connects to the same proxy all the way, then the transmission quality will become worse gradually. Thus, the mobile client should switch to a new proxy when it moves to a new subnet. In this paper, the procedure of switching the served proxies dynamically is defined as “proxy handoff”. In order to make proxy handoff smoothly, a Layered Video Forwarding Mechanism (LVFM) based on IPv6 multicast and scalable MPEG-4 streaming is proposed and implemented. LVFM can analyze the situation of cached data in the original proxy and the new proxy and then decide whether the original proxy needs to forward the cached data to the new proxy or not. Once the forwarding procedure is required, LVFM can forward the cached video frames according to the priority of each layer. LVFM forwards these layers as long as the forwarding time can be done before the corresponding layers’ presentation time is due. In order to verify the proposed LVFM, three experiments are designed and the experiment results are also presented in this paper.

An energy‐efficient protocol for multimedia streaming in a mobile environment

Pervasive services and smart environments are becoming more and more popular as an ever‐increasing number of people enjoys these services typically by means of portable devices. These devices are battery‐fed and, thus, energy efficiency is a critical factor for the deployment of pervasive services. In this paper we focus on multimedia streaming services for mobile users. Specifically, we consider a scenario where mobile users with Wi‐Fi devices access the Internet to receive audio files from a remote streaming server. We propose a proxybased architecture and an energy‐efficient streaming protocol that minimize the energy consumption of the Wi‐Fi interface at the mobile device, while guaranteeing the real‐time constraints of the audio streaming. The experimental analysis performed on a prototype implementation shows that our solution allows an energy saving ranging from 76% to 91% of the total consumption due to the network interface. Moreover, it also preserves a good user‐level Quality of Service.

멀티미디어 스트리밍 서비스를 지원하기 위한 트랜스포트 계층에서의 이동성 지원 방안

PR-SCTP를 이동환경 지원이 가능하도록 확장함으로써 이동 환경에서 멀티미디어 스트림 전송을 요구하는 응용을 지원하는 트랜스포트 계층 이동성 지원 프로토콜인 uPR-mSCTP를 제안하였다. uPR-mSCTP에서는 비순서화 비신뢰성 데이터 전송 서비스를 지원하기 위한 규칙을 정의하였고, 핸드오버 시 핸드오버 지연을 최소화할 수 있는 방안을 제안하였다. 시뮬레이션을 통해 IPv6에 uPR-mSCTP를 탑재한 경우와 UDP를 탑재한 네트워크 계층 이동성 지원 프로토콜들의 성능을 비교한 결과, uPR-mSCTP는 핸드오버 시 패킷전송률을 줄이기 때문에 네트워크 자원낭비를 줄이고, FMIPv6에 근접하는 패킷손실률을 보이며, MIPv6 HMIPv6에 비해서는 훨씬 낮은 패킷 손실률을 보임을 알 수 있었다. 또한 uPR-mSCTP는 UDP를 탑재한 네트워크 계층 이동성 지원에 비해 제어패킷 오버헤드를 줄이는 장점을 가진다. In this paper, we propose a transport layer mobility support protocol for multimedia streaming services in mobile/wireless environments by extending PR-SCTP to support mobility. We named the proposed scheme to be uPR-mSCTP. The rules related to provide unordered and unreliable data transfer, as well as an approach to minimize handover latency we proposed. Through the simulation results, it is shown that, since uPR-mSCTP reduces transmission rates during handover, not only it reduces the waste of network resources, but it also has the packet loss rate similar to FMIPv6, which is a lot smaller than UDP over MIPv6 or HMIPv6 It also incurs smaller control packet overhead compared to the network layer mobility support approaches.

Active isochronous resource manager for intense dynamic resource allocation service with IEEE1394

With the increased use of various audio/video style digital consumer appliances in home networks, the concurrent support of multiple multimedia streaming services is also clearly required in a home network. Although the isochronous transaction of IEEE 1394 is the best solution for such streaming services, the current IEEE 1394 standard specifications do not consider the dynamic management of isochronous bandwidth resources or a dynamic allocation service for isochronous resources. Accordingly, this paper presents an architecture for an isochronous resource management service that can support an intense dynamic allocation service in an IEEE 1394-based home network environment. The proposed isochronous resource manager service is also implemented using an IEEE 1394 device driver for RTLinux.

Prototype Implementation of a Proxy Caching System for Streaming Media Objects

Existing techniques for caching Web objects are not appropriate for the multimedia streaming service. In this paper, the authors focus on the proxy caching problem specifically for multimedia streaming objects. A prototype design and implementation of a proxy caching system – HUSTProxy is proposed. The main contribution of HUSTProxy is its ability of partial video caching, sending rate control and providing a more rational prefix caching size determination. These techniques are implemented in our design and are discussed in detail in this paper.

Nonstop: continuous multimedia streaming in wireless ad hoc networks with node mobility

Guaranteeing continuous streaming of multimedia data from service providers to the users is a challenging task in wireless ad hoc networks, particularly when node mobility is considered. The topological dynamics introduced by node mobility are further exacerbated by the natural grouping behavior of mobile users, which leads to frequent network partitioning. Network partitioning poses significant challenges to the provisioning of continuous multimedia streaming services in wireless ad hoc networks, since the partitioning disconnects many mobile users from the centralized streaming service. In this paper, we propose NonStop, a collection of novel middleware-based run-time algorithms that ensures the continuous availability of such multimedia streaming services, while minimizing the overhead involved. The network-wide continuous streaming coverage is achieved by partition prediction and service replication on the streaming sources and assisted by distributed selection of streaming sources on regular mobile nodes and users. The proposed algorithms are validated by extensive results from performance evaluations.

Video IBPster

At iGrid2002, members of the Logistical Computing and Internetworking (LoCI) Lab had two goals. The first was to present an application, Video IBPster, built using the tools of the Network Storage Stack that delivers DVD-quality video without dropping frames, without losing data and without specialized multi-media streaming servers. The Video IBPster demo easily played MPEG-2 video files encoded at bit-rates up to 15 Megabit/s (Mbps). The second goal was to determine performance limits when using multiple, untuned TCP streams to retrieve a striped and replicated file across a long network. Since tools built using the Network Storage Stack allow striped downloads from multiple servers in parallel and since the client machines were all connected to Gigabit Ethernet (GigE), we hoped that we would observe a linear scale up of throughput when downloading from multiple servers. Although we did see increased throughput, it was not linear.

QoS-aware middleware support for collaborative multimedia streaming and caching service

Reducing initial delay of playing time, delay jitter during playing time, and network bandwidth utilization is important for IP-based multimedia streaming services. In heterogeneous computing environments, diversity of computing power and network connection of different devices makes a stable quality of streaming service more difficult. In order to achieve these goals, our quality of service (QoS)-aware middleware for collaborative multimedia streaming and caching service exploits the proximity of a set of peer clients and temporal and spatial locality of cached media streams on these clients. Peer clients collaborate together to deliver streams to heterogeneous client(s) with QoS guarantees. Our paper shows collaborative techniques for multimedia streaming, scheduling and pre-fetching embedded in the QoS middleware architecture for dynamic group management of heterogeneous computing devices. In addition, we provide an underlying QoS-provisioning mechanism to support not only heterogeneous clients, but also dynamic configuration change of them.

Popularity-aware interval caching for multimedia streaming servers

An efficient buffer management scheme for multimedia streaming servers is presented. The proposed scheme exploits the reference popularity of multimedia objects as well as the time interval between two consecutive requests on an identical object. Through trace-driven simulations, it is shown that the proposed scheme improves the performance of multimedia servers significantly.