Abstract:
In one embodiment, a packet and a segment ID stack is received at a node. The segment ID stack includes a plurality of segment IDs, one or which is a first area-segment ID that identifies a first area of a subdivided network. One of a plurality of forwarding tables at the node is selected based on the first area-segment ID. Thereafter, the packet is forwarded based on information contained in the selected forwarding table.
Abstract:
An example method for segment routing based wide area network (WAN) orchestration in a network environment is provided and includes monitoring a segment routing (SR) enabled WAN environment in at least near real-time by a path computation element (PCE) located outside the WAN, receiving an event notification at the PCE, and performing traffic engineering using SR to reroute traffic off shortest paths. In one embodiment, where a current state of the WAN is not pre-computed, performing traffic engineering comprises optimizing routes to remove violation of any utilization policies, deploying the optimized routes in the WAN, re-optimizing routes for other parameters, and further deploying the re-optimized routes in the WAN. In another embodiment, performing traffic engineering comprises optimizing routes to remove violation of any utilization policies and for other parameters, and deploying the optimized routes in the WAN. In another embodiment, performing traffic engineering comprises deploying optimized routes in the WAN.
Abstract:
Various techniques can be used to avoid loops during network convergence after a topology change such as a failure. For example, a method can involve detecting a failure that disrupts an existing forwarding path between a node and a destination node; calculating at least one updated forwarding path from the node to the destination node; identifying a maximum time for at least a portion of the network to reach a post-convergence state with respect to the failure; until the maximum time has elapsed at the node, explicitly specifying at least a portion of the updated forwarding path in packet headers of any packets being sent from the node to the destination node; and after the maximum time has elapsed at the node, non-explicitly specifying the portion of the updated forwarding path in packet headers of any additional packets being sent from the node to the destination node.
Abstract:
A method, apparatus, and computer-readable storage medium for processing shared risk group (SRG) information in communications networks are disclosed. The method includes receiving network information comprising SRG information from a second domain at a first domain, obtaining at least one SRG identifier by processing the SRG information, and processing the at least one SRG identifier, the processing using processing criteria. The apparatus includes a network interface adapted to receive network information comprising shared risk group information, a processor coupled to the network interface and configured to execute one or more processes, and a memory coupled to the processor and adapted to obtain at least one SRG identifier by processing the SRG information and to process the at least one SRG identifier using processing criteria. The computer-readable storage medium is configured to store program instructions that when executed are configured to cause the processor to perform the method.
Abstract:
In one embodiment, a method includes receiving at a node in a first network, information identifying a spare interface between a first network device in the first network and a second network device in a second network, and using the spare interface to create a path in the first network if the spare interface is compatible. The spare interface information includes connectivity and compatibility information.
Abstract:
One or more functions to be performed on a packet at one or more network nodes along a network path are determined at a network device. A packet is generated which includes a packet header. Included in the packet header are an instruction pointer and an instruction portion. A first instruction for the one or more functions to be performed at the one or more network nodes is written to the instruction portion. Additionally, a value pointing to the first instruction is written to the instruction pointer. The packet is transmitted along the network path from the network device.
Abstract:
An apparatus and method are disclosed for fast reroute (FRR) for native segment routing (SR) traffic. In one embodiment, a node receives a packet that includes a segment routing (SR) segment identifier (ID) stack. The node determines what type of segment is designated as the active segment in the segment ID stack. Based, at least in part on the type of active segment, the node selects an update routine out of several possible update routines and performs the selected update routine. The update routine modifies the segment ID stack.
Abstract:
A method and apparatus for forwarding packets through a network domain that contains nodes that are label distribution protocol (LDP) enabled and nodes that are segment routing (SR) enabled. In one embodiment, the method may include a network node receiving a packet with a label attached thereto. The node swaps the label with a segment identifier (ID). The node then forwards the packet to an SR node. In another embodiment, the method may include a network node receiving a packet with a segment ID attached thereto. The node swaps the segment ID with a label. The node then forwards the packet to an LDP enabled node.
Abstract:
An apparatus and method for using indexed segment identifiers in segment routing. An example method involves receiving a globally unique index value at a node. The method also involves receiving a base value at the node, where the base value comprises a segment routing value configured to identify a nodal segment. The method then involves calculating a segment identifier based on the index value and the base value.
Abstract:
A method, apparatus, and computer-readable storage medium for processing shared risk group (SRG) information in communications networks are disclosed. The method includes receiving network information comprising SRG information from a second domain at a first domain, obtaining at least one SRG identifier by processing the SRG information, and processing the at least one SRG identifier, the processing using processing criteria. The apparatus includes a network interface adapted to receive network information comprising shared risk group information, a processor coupled to the network interface and configured to execute one or more processes, and a memory coupled to the processor and adapted to obtain at least one SRG identifier by processing the SRG information and to process the at least one SRG identifier using processing criteria. The computer-readable storage medium is configured to store program instructions that when executed are configured to cause the processor to perform the method.