Techniques for determining an alternative communication mode for vehicle-to-vehicle communication at a host vehicle can include monitoring the primary mode of RF communication to ensure it is effectively communicating and, if not, intelligently selecting a backup communication mode comprising one or more other sensors and/or systems of the vehicle. The selection of the backup communication mode may take into account various factors that can affect the various modes of communication from which the backup communication mode is selected.

In an optical communications network, the supervisory control signal is duplicating at the OSI layer 2 or layer 3 level to generate a primary supervisory control signal and a secondary supervisory control signal. Access to the primary supervisory control signal is enabled at a network interface of a network device. In response to detecting a failure of the optical communications network or the device, access to the primary supervisory control signal is disabled and access to the secondary supervisory control signal is enabled.

In an optical communications network, the supervisory control signal is duplicating at the OSI layer 2 or layer 3 level to generate a primary supervisory control signal and a secondary supervisory control signal. Access to the primary supervisory control signal is enabled at a network interface of a network device. In response to detecting a failure of the optical communications network or the device, access to the primary supervisory control signal is disabled and access to the secondary supervisory control signal is enabled.

The disclosed systems, structures, and methods are directed to an optical communication system. The optical communication system comprising an optical node configured to receive a light signal, in which the light signal is received from a first optical path and a second optical path, and the optical node is further configured to determine a change in state of polarization (SOP) of the light signal received from the first optical path and the second optical path, a processing unit configured to determine if at least a portion of the first optical path and the second optical path has a/similar change in SOP.

Embodiments of the present disclosure include a pluggable optical line system module for amplification, multiplexing, and demultiplexing of coherent optical signals that can be integrated with a switch-router. Integration may include mechanical, electrical, and software control aspects. One example embodiment of the optical line system is in an industry standard small form factor pluggable module such as OSFP (octal small form factor pluggable) or QSFP (quad small form factor pluggable). When configured in a switch-router, the pluggable optical line is powered, managed and controlled by the switch-router which greatly reduces the cost, space, power and the management complexity of optical line systems.

Embodiments of the present disclosure include a pluggable optical line system module for amplification, multiplexing, and demultiplexing of coherent optical signals that can be integrated with a switch-router. Integration may include mechanical, electrical, and software control aspects. One example embodiment of the optical line system is in an industry standard small form factor pluggable module such as OSFP (octal small form factor pluggable) or QSFP (quad small form factor pluggable). When configured in a switch-router, the pluggable optical line is powered, managed and controlled by the switch-router which greatly reduces the cost, space, power and the management complexity of optical line systems.

Embodiments disclosed herein provide a hybrid fiber-copper access network in which a main OLT sends data to the DSLAMs via a plurality of point-to-point optical fiber connections. A standby OLT is provided which has a plurality of point-to-multi-point optical fiber connections to the DSLAMs. In the event of a failure, data can be sent to some of the DSLAMs via the standby OLT and the point-to-multi-point optical fiber connections. Following the rectification of the fault, the network can revert to its normal state and transmit data to the DSLAMs via the main OLT and the plurality of point-to-point optical fiber connections.

Embodiments disclosed herein provide a hybrid fiber-copper access network in which a main OLT sends data to the DSLAMs via a plurality of point-to-point optical fiber connections. A standby OLT is provided which has a plurality of point-to-multi-point optical fiber connections to the DSLAMs. In the event of a failure, data can be sent to some of the DSLAMs via the standby OLT and the point-to-multi-point optical fiber connections. Following the rectification of the fault, the network can revert to its normal state and transmit data to the DSLAMs via the main OLT and the plurality of point-to-point optical fiber connections.

A protection switching method, including sending, by a first end node, a first protection switching request message to an intermediate node in response to a fault occurring on a working path between the first end node and a second end node, wherein a protection path of the working path comprises the first end node, the second end node, and at least one intermediate node, receiving, by the first end node, a second protection switching request message from the intermediate node, and switching service data to the protection path for transmission in response to receiving the second protection switching request message, where one overhead frame of each of the first and second protection switching request messages has at least two overhead information groups, and each of the at least two overhead information groups comprises a request type field, a request signal identifier field, and a bridge flag field.

A protection switching method, including sending, by a first end node, a first protection switching request message to an intermediate node in response to a fault occurring on a working path between the first end node and a second end node, wherein a protection path of the working path comprises the first end node, the second end node, and at least one intermediate node, receiving, by the first end node, a second protection switching request message from the intermediate node, and switching service data to the protection path for transmission in response to receiving the second protection switching request message, where one overhead frame of each of the first and second protection switching request messages has at least two overhead information groups, and each of the at least two overhead information groups comprises a request type field, a request signal identifier field, and a bridge flag field.