OPTICAL SWITCHING SYSTEM

An optical switching unit requiring no optical-to-electrical conversions on optical data paths being switched through the optical switching unit. The optical switching unit receives optical data information from one terminal and switches it to another terminal. The optical switching unit frame synchronizes the data transmission timing of the terminals in accordance with the data transmission timing of the optical switching unit. This frame synchronization eliminates the need toprovide data buffering and frame synchronization in the optical switching unit. The optical switching unit comprises an optical network, system clock, optical inputinterfaces for receiving information from terminals, and optical output interfaces for transmitting information to terminals. The system clock determines the timing ofeach terminal using information transmitted to an optical input interface by theterminal. If the timing of a terminal does not match that of the system clock, the system clock blocks the transfer of data information by the optical input interface to the optical network and transmits timing information to the terminal via an optical output interface. If the timing matches, the system clock signals the optical input interface to communicate the data information to the optical network which switches the data information to optical output interfaces for transmission to terminals.