Patent ID: 7212739

Claim:
A protection switching arrangement comprising: a first layer for switching a plurality of optical channel signals; a second layer, coupled to said first layer, for switching a plurality of optical channel signal groups, each optical channel signal group including at least one of said optical channel signals, said second layer comprising: a plurality of optical channel group switches, each including a plurality of input ports; and a protection optical channel group switch including a plurality of input ports; an optical protection switch, coupled to said second layer, for providing in said second layer an alternative switch path for each of said optical channel signal groups, said optical protection switch including a plurality of output ports and a protection output port, each output port of said optical protection switch being coupled to a respective input port of a respective one of the optical channel group switches, said protection output port of said optical protection switch being coupled to one of said input ports of said protection optical channel group switch so as to provide said alternative switch path.