Abstract: Network routes are assessed using a routing policy. The routing policy includes policy directives. A point of application in a policy directive specifies a program statement that can be immediately executed without having to make a function call. Stated differently, the program statement can be immediately executed from the point of application in the policy directive without the program statement having to be incorporated in a function.

Abstract: User commands to export and import routes between a customer-facing VRF and a core-facing VRF in a PE device can include two filters. An export command installs VPN paths in the core-facing VRF based on VRF paths in a customer VRF. An export command includes a filter that selects VRF paths in the customer VRF from which VPN paths are generated. An editor function edits the generated VPN paths prior to being stored in the core-facing VRF. Conversely, an import command includes a filter that selects VPN paths in the core-facing VRF from which VRF paths are generated. An edit function edits the generated VRF paths prior to being stored in the customer VRF.

Abstract: A routing policy includes policy directives and policy functions. Execution of the routing policy includes invoking a policy function at a point of application in a policy directive. Execution of the invoked policy function can include making any number of nested function calls. When an EXIT statement is encountered in a nested policy function, execution of the policy function terminates and execution of the routing policy continues immediately with the policy directive following the point of application, irrespective of how deeply nested in the invocation hierarchy the policy function is.

Abstract: A routing policy includes policy directives and policy functions. Execution of the routing policy includes invoking a policy function at a point of application in a policy directive. Execution of the invoked policy function can include making any number of nested function calls. When an EXIT statement is encountered in a nested policy function, execution of the policy function terminates and execution of the routing policy continues immediately with the policy directive following the point of application, irrespective of how deeply nested in the invocation hierarchy the policy function is.

Abstract: A network device that provides packet forwarding services includes: a command line interface and a route manager. The command line interface is programmed to: obtain a command, for updating a routing control function, that specifies positional information; identify a portion of the routing control function based on the positional information; identify a syntactic style associated with the portion of the routing control function; make a modification to the routing control function to obtain a modified routing control function; and update operation of the network device based on the modified routing control function. The route manager is programmed to process a route for forwarding packets of the network device based on the modified routing control function, after the operation of the network device is updated, to obtain a processed route for forwarding the packets.

Abstract: A network device that provides packet forwarding services includes: a command line interface and a route manager. The command line interface is programmed to: obtain a command, for updating a routing control function, that specifies positional information; identify a portion of the routing control function based on the positional information; identify a syntactic style associated with the portion of the routing control function; make a modification to the routing control function to obtain a modified routing control function; and update operation of the network device based on the modified routing control function. The route manager is programmed to process a route for forwarding packets of the network device based on the modified routing control function, after the operation of the network device is updated, to obtain a processed route for forwarding the packets.

Abstract: A network device that provides packet forwarding services includes: a command line interface and a route manager. The command line interface is programmed to: obtain a command, for updating a routing control function, that specifies positional information; identify a portion of the routing control function based on the positional information; identify a syntactic style associated with the portion of the routing control function; make a modification to the routing control function to obtain a modified routing control function; and update operation of the network device based on the modified routing control function. The route manager is programmed to process a route for forwarding packets of the network device based on the modified routing control function, after the operation of the network device is updated, to obtain a processed route for forwarding the packets.

Abstract: Novel mechanisms for compiling routing policies and evaluating network routes, including: (a) an efficient mechanism for representing routing policies to facilitate the runtime evaluation of network routes; (b) a mechanism for late-binding vectors pertaining to external constructs used or recited within the routing policies; and (c) a mechanism for updating routing policy state pertinent to network route evaluation. Existing methods for evaluating network routes on a network device, such as the use of route maps, tend to introduce complexity and extend route evaluation runtime when performing, for example, certain operations to one or more route attributes for any given network route being evaluated. Through implementation of disclosed mechanisms, however, route evaluation runtimes may be reduced, thereby minimizing, if not eliminating, any route evaluation congestion.

Abstract: A method for enabling access to varying route attribute states during routing policy application on network devices. Concerning routing policy configurations, it is currently possible to evaluate network routes based on a singular state of one or more route attributes. In some scenarios, however, access to more than one state of the route attribute(s) is desirable. In addressing these scenarios, the disclosed method introduces state namespaces through which different states of the routing attribute(s) are maintained and accessed.