Bounds on the mean system-size and delay for a movable-boundary integrated circuit and packet switched communications channel

A multiaccess communications channel which is shared on an integrated circuited-switched and packet-switched basis is considered. Applications include time-division multiplexing and demand-assigned/TDMA communication channels which are shared by circuit-switched services (such as isochronous voice) and packet-switched services (such as data). Frames of fixed duration are established and divided into two parts: one part is used for voice transmissions while the other part serves to accommodate packetized data traffic. These two parts are separated by a movable boundary, so that data traffic can use the frame capacity which is temporarily unoccupied by voice transmissions. An exact expression is derived for the mean packet queue-size and delay. To reduce the computational complexity involved in using this expression, simpler expressions for upper and lower bounds are derived for the mean packet queue-size and packet delay. Examples demonstrating the tightness of these numerically efficient bounds are presented.