Method and optical communication network for bidirectional protection protocols

An optical communication network having at least two network transmission paths for carrying switched signals and unswitched signals, said optical communication network comprising:

• a first processing means for processing said switched signals in accordance with a first protection protocol;
• a second processing means for processing said unswitched signals in accordance with a second protection protocol, said second protection protocol being different than said first protection protocol;
• a primary add/drop mechanism for selectively adding and dropping said switched signals on said at least two transmission paths;
• a unswitched add/drop mechanism for selectively adding and dropping said unswitched signals on said at least two transmission paths;
• whereby said primary add/drop mechanism and said second add/drop mechanism are configured to add and drop said switched and said unswitched signals to counter-propagate along said at least two network transmission paths.

A method of operating a redundant optical communication network having at least two network transmission paths for carrying one or more switched signals and one or more unswitched signals, said method comprising:

• assigning a first protection protocol to said switched signals;
• assigning a second protection protocol to said unswitched signals, said second protection protocol being different than said first protection protocol;
• selectively adding and dropping said switched signals on said at least two transmission paths;
• and
• selectively adding and dropping said unswitched signals on said at least two transmission paths;
• whereby said adding and dropping are performed such that said switched signals and said unswitched signals are counter-propagating along said at least two network transmission paths;
• wherein said optical communication network is a ring and said switched signals and said unswitched signals are selectively added and dropped at different location on said ring
• wherein said selective adding and dropping of said unswitched signals is performed by a circulator and selective adding and dropping-of said switched signals is performed by an optical add/drop mechanism.