Abstract: A path protection method includes receiving, by a source node of a first path, a path event notify message from a first node on the first path. The path event notify message includes indication information that the first path is predicted to fail. The path protection method further includes obtaining, by the source node, information about a predicted protection path. The information about the predicted protection path includes resource information of a second path useable to protect a service on the first path. The first path and the second path include the source node and a same sink node. The path protection method further includes storing, by the source node, the resource information of the second path.

Abstract: Embodiments of this application provide a service protection method, including: A first node determines that a fault occurs on a first working path; the first node generates a bandwidth activation message based on the fault, where the bandwidth activation message indicates a third node to adjust a bandwidth of a service from a protection bandwidth to a target bandwidth, the protection bandwidth represents a pre-occupied bandwidth of a first protection path before transmission of the service, and the target bandwidth represents an actual occupied bandwidth for transmission of the service; and the first node sends the bandwidth activation message on the first protection path.

Abstract: This application discloses a same-cable probability detection method. The method includes: obtaining a first characteristic parameter of a first optical signal and a second characteristic parameter of a second optical signal, where the first optical signal is a signal transmitted in a first optical fiber, the second optical signal is a signal transmitted in a second optical fiber, the first characteristic parameter is generated after the first optical signal is affected by a vibration of the first optical fiber, and the second characteristic parameter is generated after the second optical signal is affected by a vibration of the second optical fiber; and obtaining, based on the first characteristic parameter and the second characteristic parameter, a probability that at least one optical cable segment of the first optical fiber and at least one optical cable segment of the second optical fiber include a same-cable segment.

Abstract: Embodiments of this application relate to the field of communication technologies, and provide a routing information publishing method. The method includes: An edge transport device connected to a first edge device in a first network domain receives, based on a control plane protocol message, first routing information that is from a controller and that includes an address of a second edge device in a second network domain and a destination address of the second network domain, and sends the first routing information to the first edge device, so that the first edge device generates, based on the first routing information, a forwarding table that is of the first edge device and that is used to indicate a forwarding relationship between the first network domain and the second network domain.

Abstract: A path protection method includes receiving, by a source node of a first path, a path event notify message from a first node on the first path. The path event notify message includes indication information that the first path is predicted to fail. The path protection method further includes obtaining, by the source node, information about a predicted protection path. The information about the predicted protection path includes resource information of a second path useable to protect a service on the first path. The first path and the second path include the source node and a same sink node. The path protection method further includes storing, by the source node, the resource information of the second path.

Abstract: Embodiments of this application relate to the field of communications technologies. The embodiments of this application are applicable to a centralized management and control network. A centralized controller obtains Z service requests, globally determines, based on an identifier of a source service node and an identifier of a destination service node that are corresponding to each of the Z service requests, a quantum key consumption parameter, and topology information of key nodes in the centralized management and control network, globally optimal key relay instructions corresponding to G service requests, and further delivers the key relay instructions corresponding to the G service requests to key nodes corresponding to the key relay instructions, so that the key nodes perform quantum key relay based on the key relay instructions, to generate a shared quantum key between the source key node and the destination key node.

Abstract: The present invention discloses a method for handling channel failures in an Automatically Switched Optical Network (ASON). When a channel alarm occurs, the head service node decides whether the channel alarm is incurred by a channel failure according to the alarm message or alarm information. If so, the head and end service nodes continue to locate whether the channel failure is inside or outside the network by combining local detection and message notification. If the channel failure is an internal failure, rerouting is activated to locate and remove the channel failure. When this method is used to locate a channel failure, the amount of information exchanged is small. The method may quickly identify the accurate position of a failure inside the network, improve the efficiency in removing failures, and minimize the damages to services, with little harm to equipment functioning and network performance.

Abstract: A method for clock tracing in a network and a method for clocking tracing, the method for clock tracing in a network includes: distributed network element or a centralized server in the network determining a shortest path to each of clock-source network elements according to stored network topology information and clock-tracing link weight information; determining, among clock sources provided by reachable clock-source network elements, one with an optimal quality, where a clock-source network element with that clock source being considered optimal; and taking a shortest path to the optimal clock-source network element as a clock-tracing path. Furthermore, the method for clocking tracing uses such a clock-tracing path for clock tracing.

Abstract: The present invention discloses a method for handling channel failures in an Automatically Switched Optical Network (ASON). When a channel alarm occurs, the head service node decides whether the channel alarm is incurred by a channel failure according to the alarm message or alarm information. If so, the head and end service nodes continue to locate whether the channel failure is inside or outside the network by combining local detection and message notification. If the channel failure is an internal failure, rerouting is activated to locate and remove the channel failure. When this method is used to locate a channel failure, the amount of information exchanged is small. The method may quickly identify the accurate position of a failure inside the network, improve the efficiency in removing failures, and minimize the damages to services, with little harm to equipment functioning and network performance.

Abstract: The invention discloses a method for calculating constrained paths for a transmission network. The method has the capability of automatic calculation of the shortest paths satisfying the SDH/SONET protection requirement, and can effectively reduce repeat computation times. The method comprises the steps of: collecting attribute information of the link to which each node is connected and obtaining the number of the protect entity to which the link belongs; flooding the collected information to other nodes according to a protocol; combining each node according to the numbers of the protection entities to which each link respectively belongs and forming the topology structure of each protection entity of whole network and related link attribute information; and calculating constrained paths for the transmission network. Since the protection topology is pre-calculated in this method, the repeat computation times can be effectively reduced and the constrained paths can be calculated in real time.