摘要:
A system for use in a bi-directional path switched ring network for detecting a failed optical path and establishing a protection path so as to allow signals from the failed optical path to be re-routed via the protection path is provided. According to one aspect of the system, upon detecting a failure relating to an optical path, the destination node generates a connection request message for transmission to the source node. The connection request message is passed to the source node via one or more intermediate nodes, if any. Each intermediate node examines the connection request message accordingly reserves the requisite wavelength from the protection capacity so as to allow signals from the failed optical path to be re-routed. Upon receiving the connection request message, the source node readies its switching equipment to re-route signals from the failed optical path and generates an acknowledgment message and propagates it back to the destination node via the intermediate nodes. The intermediate nodes and the destination node, upon receipt of the acknowledgement message, also ready their respective switching equipment to carry the re-routed signals via the previously reserved wavelength from the protection capacity. According to another aspect of the system, a contention resolution mechanism is provided to resolve contending connection request messages received at a node requesting the same wavelength to be reserved from the protection capacity for different failed optical paths. A message format is used for the connection request which allows the connection request message to include information relating to the type of failure experienced by a failed optical path and other priority data. Such information is then used by a node to determine priority between two contending connection request messages.
摘要:
An optical wavelength cross connect is provided to receive multiple input optical signals that each have multiple spectral bands and to transmit multiple output optical signals that each have one or more of those spectral bands. The optical wavelength cross connect includes multiple wavelength routing elements, which are optical components that selectively route wavelength components between one optical signal and multiple optical signals in either direction according to a configurable state. As used within the optical wavelength cross connect, each of the wavelength routing elements receives at least one optical signal corresponding to one of the input optical signals. A mapping of the spectral bands to the output optical signals is determined by the states of the wavelength routing elements.
摘要:
An method, apparatus, and computer program product for restoring a failed system in an optical mesh network. A system includes a first light termination element (LTE) and a second LTE. A first node in the network includes an optical switching unit (OSU) coupled to the first (LTE) of the system. A second node in the network includes a second OSU coupled to the second (LTE) of the system. The first node is coupled to the second node by a path. Optical data traffic can be transmitted between the first node and the second node via the path. Upon detection of a failure of the system, the first OSU and second OSU are notified of the failure. A primary role is assigned to one of the first and second OSUs, and a secondary role is assigned to the other one of the first and second OSUs. A primary restoration plan is determined by the primary OSU. Information identifying the primary restoration plan is sent from the primary OSU for effecting the restoration path to restore the system.
摘要:
An method, apparatus, and computer program product for restoring a failed system in an optical mesh network. A system includes a first light termination element (LTE) and a second LTE. A first node in the network includes an optical switching unit (OSU) coupled to the first (LTE) of the system. A second node in the network includes a second OSU coupled to the second (LTE) of the system. The first node is coupled to the second node by a path. Optical data traffic can be transmitted between the first node and the second node via the path. Upon detection of a failure of the system, the first OSU and second OSU are notified of the failure. A primary role is assigned to one of the first and second OSUs, and a secondary role is assigned to the other one of the first and second OSUs. A primary restoration plan is determined by the primary OSU. Information identifying the primary restoration plan is sent from the primary OSU for effecting the restoration path to restore the system.