Reservation-arbitrated access for isochronous voice transport over dual-bus metropolitan area networks

This paper proposes a reservation-arbitrated (RA) access protocol for isochronous voice transport over IEEE 802.6 MANs. Fully compatible with the IEEE 802.6 cell and frame formats, RA access allows full statistical multiplexing among voice calls, enabling significant improvements in channel utilization compared to pre-arbitrated (PA) access. The protocol employs random access to acquire a voice channel at the beginning of each talkspurt, and if successful, reserve the bandwidth in succeeding frames for the duration of the talkspurt. While the initial access at the beginning of each talkspurt is subject to variable delay and possible clipping, these distortions can be kept to acceptable levels. System performance is analyzed by simulation, and performance improvement through slot reuse is also considered