Patent ID: 7787763

Claim:
A method for providing protection for a network, comprising: establishing a light-trail through a sequence of nodes of an optical network, the sequence of nodes coupled by a first fiber and by a second fiber, the first fiber comprising a first optical fiber, the second fiber comprising a second optical fiber, each fiber passing through a transport element of each node, each node of the light-trail comprising a wavelength blocking unit; configuring the wavelength blocking units of a beginning node of the light-trail and an end node of the light-trail to block a plurality of optical signals of a common wavelength; configuring the wavelength blocking units of a plurality of intermediate nodes of the light-trail to allow the plurality of optical signals of the common wavelength; communicating traffic through a plurality of connections of the light-trail, the traffic comprising the plurality of optical signals of the common wavelength, a connection operable to communicate traffic from a source node of the sequence of nodes, through one or more intervening nodes of the sequence of nodes, to one or more destination nodes of the sequence of nodes using the common wavelength; detecting that the light-trail has a failure; establishing a protection light-trail corresponding to the light-trail, the protection light-trail configured to communicate the traffic comprising the plurality of optical signals of the common wavelength, the establishing the protection light-trail corresponding to the light-trail further comprising: determining a failed span comprising the failure, the first fiber comprising an upstream remnant segment and a downstream remnant segment, the upstream remnant upstream from the failure, the downstream remnant downstream from the failure; creating a wrap-around segment from a portion of the second fiber, the wrap- around segment comprising a loop-back path of the failed span; and establishing the protection light-trail from the upstream remnant segment, the wrap-around segment, and the downstream remnant segment; and communicating the traffic of the plurality of connections through the protection light-trail.