Isochronous versus synchronous traffic in FDDI

Abstract

In this paper a summary of the advantages and disadvantages of isochronous and synchronous transport services of the fiber distributed data interface (FDDI) are summarized. A comparison of both services is made based on application requirements (e.g. real-time video and voice). These requirements include timing constraints, such as jitter and delay, bandwidth utilization, and end-station requirements. It is shown that synchronous traffic can support a wide range of application requirements efficiently at moderate cost when the connections between source and destination are on the same physical ring. However, isochronous traffic has advantages, particularly when the network traffic is well behaved (the peak data rate is close to the mean data rate) and when connections traverse multiple rings.