Multimedia over FDDI

Abstract

This paper focuses on issues in multimedia networking over FDDI and simulation results demonstrating the feasibility of multimedia over FDDI. Previous work in this field has concentrated on the asynchronous channel in FDDI. Other examinations of the FDDI synchronous channel have applied bursty tr&c to the synchronous channel. Multimedia trajjk is typically stream oriented.Our simulations were focused on simulating typical configurations with a range of applications and traffic models. The advantages of FDDI as an integrated voicelvideol data network are demonstrated. 1: IntroductionThe paper is organized as follows.A brief discussion on the basics of FDDI and multimedia is followed by an overview of the various multimedia applications and issues in networking of multimedia applications such as voice and video. The importance of parameters such as network delay, intrapacket jitter, and bandwidth is highlighted.The simulation models are discussed. The methodology involved testing the effect of variations in 'ITRT, network size, packet size, and offered load on the multimedia streams of voice and video, using the IRI Planystm tool.Finally, the simulation results for running multimedia over the FDDI synchronous channel are discussed. A comparison of multimedia over FDDI synchronous and asynchronous channels is made demonstrating the ability of the synchronous channel to provide a near-constant latency and bandwidth under various loads and configurations. 1.1: FDDIBasicsFDDI is a 100 Mbps high speed local area network standard developed under the auspices of American National Standards Institute (ANSI) X3T9.5 committee.Unlike other LANs whose origins were proprietary products, FDDI was developed by a group of people whose interest was to create a reliable fault-tolerant, high-speed network connecting numerous stations over greater distances than existing standards. The ANSI X3T9.5 committee thus developed a specification for a network based on a dual counter-rotating fiber optic ring using timed-token protocol, which is capable of transmitting data at 100 Mbps in each ring and which can extend to 500 stations over a total fiber length of 200 km with full system performance.The FDDI MAC supports multiple classes of service:Synchronous, Asynchronous and Restricted Asynchronous. The asynchronous class is used for normal, bursty data traffic. For more constant, isochronous traffic, the synchronous channel can be used and it provides guaranteed bandwidth to each station on each token rotation. The restricted asynchronous service provides a mechanism h r extended and protected dialog between a limited number of stations. ' Lhis feature is rarely used.There have been several publications on FDDI [lo], [111,[12], [131, [14], [15], [16] which explain the protocol in further detail. 2: MultimediaMultimedia is a term used to denote a set of applications, products, and technologies 113. We define it as the use of multiple means to communicate information via a computer. Whereas computers today are mainly used for textual data inf...

MPEG transmission schemes for a timed token medium access control network

“…It is because the human eye can hardy recognize a frame which is out of synchronization within 3 frame-time --that is 1/10 second. Studies by Shah et al [SHA92] have shown that our vision system will recognize a sequence of frames as distinct pictures if the display rate is at 8 frames per second or lower. Between 10 to 12 frames per second, the frame sequence would appear to be choppy.…”

Retransmission-based Error Control for Continuous Media Traffic in Packet-switched Networks

“…The phenomenon has been studied extensively, however, for participants in interactive phone conversations [35], and these results provide rst-order information on the delays acceptable in other interactive applications. Table 1.1 gives a summary of the eects of roundtrip delay on speech quality (adapted from [53]). In general, high-quality voice applications require less than 200 ms roundtrip delays, but delays of up to 600 ms have been shown to be acceptable [35].…”

Performance of high-speed networks for multimedia applications

“…This application involves the transmission of audio, visual and textual instructions. The total traffic volume for each multimedia session is 6.877 Mbps [22] . Figure 2 shows the maximum number of multimedia sessions a network protocol can support at various data transfer rates.…”

“…This application also contains audio and textual data. The total traffic volume per multimedia session is 3.594 Mbps [22] . The traffic volume for this application is almost half of that for the interactive educationltraining application.…”

“…It has an even lower traffic volume than our previous multimedia applications. Table 9 lists the parameters; the overall traffic volume for each video conference session is just 1.594 Mbps [22] . When we compare Figure 8 with Figure 10, we see that each protocol can support more sessions in the video conference workload set, but the relative performance stays the same.…”