System and method for sharing a spare channel among two or more optical ring networks

An optical communications system having a first optical ring network and a second optical ring network, wherein the first optical ring network has a first ring element and a second ring element, and wherein the second optical ring network has a first ring element and second ring element, comprising:

• a first optical cross-connect switch coupled to a first controller, controller including a first switching table, said first switching table having an event column and an action column, and optically coupled to the first ring element of the first optical ring network and to the first ring element of the second optical ring network, said first controller including first receiving means for receiving failure indications from the first ring element of the first optical ring and from the first ring element of the second optical ring;
• a second optical cross-connect switch coupled to a second controller optically coupled to the second ring element of the first optical ring network and to the second ring element of the second optical ring network, said second controller including second receiving means for receiving failure indications from the second ring element of the first optical ring and from the second ring element of the second optical ring;
• and
• a spare channel optically coupled between said first optical switching unit and said second optical switching unit, wherein
• the first ring element of the first optical ring transmits a first ring failure indication to said first controller upon the first ring element of the first optical ring sensing a ring failure in the first optical ring, and
• the second ring element of the first optical ring transmits a second ring failure indication to said second controller upon the second ring element of the first optical ring sensing a ring failure in the first optical ring;
• said first optical switching unit selectively optically couples one of the first ring element of the first optical ring and the first ring element of the second optical ring to said spare channel;
• and
• said second optical switching unit selectively optically couples one of the second ring element of the first optical ring and the second ring element of the second optical ring to said spare channel.