Optical ATM self-routing switching system with optical copy network

摘要

In an optical ATM switching system, an optical (2 x 2) copy network 2230 is provided in a preceding stage of an optical self-routing network for multicasting an ATM cell to as many outlets of the self-routing network as there are routing (copying) bits contained in the optical header of the cell. The system includes interface units 2201 and 2202 through which electrical ATM cells from the associated transmission lines are received and converted to optical form for coupling through wave guides 2211 and 2212 to the copy network. The interface units are connected to a multicast controller 2220 which generates a multicast control signal indicating the number of "copying" bits to be inserted to the optical header of ATM cells as well as the time slot positions of the copying bits in the optical header.