Composite add/drop multiplexor
A telecommunications node architecture is disclosed that comprises multiple add/drop multiplexors that are interconnected in a novel topology to enhance the reliability of the telecommunications network. Furthermore, the architecture of the illustrative embodiment ameliorates the well-known “add-before-drop” problem.
1. An apparatus comprising:
a) a first add/drop multiplexor comprising:
i) a first input for receiving a first signal from a first node,
ii) a first output for transmitting a second signal to a second node,
iii) a second input for receiving a third signal from a first output of a second add/drop multiplexor, and
iv) a second output for transmitting a fourth signal to a first input of said second add/drop multiplexor; and
b) said second add/drop multiplexor comprising:
i) said first input for receiving said fourth signal from said second output of said first add/drop multiplexor,
ii) said first output for transmitting said third signal to said second input of said first add/drop multiplexor,
iii) a second input for receiving a fifth signal from said second node, and
iv) a second output for transmitting a sixth signal to said first node.
2. The apparatus of claim 1 wherein said first node is a SONET/SDH node and said first signal is a series of SONET/SDH frames.