Efficient trap avoidance and shared protection method in survivable networks with shared risk link groups and a survivable network

An iterative shared protection for selecting an active path (AP) and a corresponding (BP) in a survivable network with shared risk link groups while avoiding traps, comprising:

• selecting an AP in a first optical network, wherein said AP comprises a set of links and connects first and second nodes in said first optical network;
• selecting a BP for said AP, wherein said BP said BP connects said first and second nodes;
• evaluating said BP to determine whether said BP is shared risk link group (SRLG)-joint with said first AP;
• determining said BP is SRLG-joint with said first AP;
• identifying a high risk link in said set of links;
• removing said high risk link from said first optical network to form a new optical network;
• and,
• repeating said steps of selecting an AP, selecting a BP, evaluating said BP, determining, identifying, and removing until said evaluation determines said BP is SRLG-disjoint with said first AP.

An iterative shared protection for selecting an active path (AP) and a corresponding (BP) in a survivable network with shared risk link groups while avoiding traps, comprising:

• selecting a first AP in a first optical network, wherein said first AP comprises a set of links and connects first and second nodes in said first optical network;
• selecting a BP for said first AP, wherein said BP said BP connects said first and second nodes;
• evaluating said BP to determine whether said BP is shared risk link group (SRLG)-joint with said first AP;
• determining said BP is SRLG-joint with said first AP;
• identifying a high risk link in said set of links;
• and,
• removing said high risk link from said first optical network to form a respective optical network;
• and,
• wherein said first optical network comprises a BP set comprising every BP connecting said first and second nodes;
• and,
• said method further comprising:
• repeating said steps of selecting a first AP, selecting a BP, evaluating said BP, determining, identifying, and removing until every BP in said BP set is found to be SRLG-joint with said first AP.