Time slot switching for integrated services in fiber optic PBX/LAN

A new medium access prolocol called time slot switching (TSS) is proposed for use in optical fiber local area networks. This protocol incorporales features of time division, space division, and time compression for users to share a common medium. VLSI CMOS electrical crosspoints are used to switch traffic within individual time slots. Wilh these features, data, voice, and video services can all be combined in a single network, In addition, the speed of the eleclronics can be maximized to match the available optical bandwidth. Operational principles of the TSS protocol are explained. A performance analysis is presented to show the tradeoffs among traffic capacity, frame guard time, blocking probability, and transmission delay. The analysis is done for 64 Kbit/s channels, and the results show that TSS is more attractive than broadcast protocols for voice traffic or constant-rate data traffic. An approach to integrating voice, data, and video traffic within TSS is also described.