Abstract: In one embodiment, a method includes generating a subgraph from a dependency graph. The subgraph includes one or more potential paths between an event interest node and an event generator node of the dependency graph. The method also includes activating the event interest node and assigning, in response to activating the event interest node, a color to nodes along the one or more potential paths of the subgraph from the event interest node to the event generator node. The method further includes modifying the event generator node and modifying, in response to modifying the event generator node, one or more of the nodes along the one or more potential paths of the subgraph from the event generator node to the event interest node.

Abstract: A novel method for provisioning network services for a cable system is provided. The method provides a configuration command interpreter/compiler that receives configuration commands of the cable system and generates configuration commands understood by the actual physical devices implementing the cable system. The interpreter transforms the configuration commands of the cable system into the configuration commands of the actual physical devices based on a set of normalized data models describing the cable system. The normalized data models are applicable to the cable system regardless of the actual devices implementing the cable system. The normalized data models are specified using normalized parameters that are generally applicable to different types devices that can be used to implement the cable system.

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. The packet engine is configurable to selectively provide L3 level routing or L2 level switching/bridging between different logical interfaces. In some embodiments, the controller selects between configuring the packet engine to perform L3 routing or configuring the packet engine to perform L2 bridging based on whether the packet engine support unnumbered interfaces and integrated routing and bridging (IRB).

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. Upon receiving upstream data packet from a particular cable service flow, the remote distribution node applies a set of tags or labels to the data packet identifying the data packet as being from the particular cable service flow. The remote distribution node then forwards the tagged packet toward the packet engine, where the tags/labels are used to direct the packet toward the corresponding logical interface of the particular cable service flow.

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. Each service flow is assigned a class of service (CoS) at the packet engine and guarantee a certain level of quality of service (QoS). In some embodiments, each cable service flow is assigned a CoS priority number. For each possible CoS priority number, the packet engine is configured to provide certain resources at certain quality level, i.e., certain level of QoS.

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. The packet engine is configurable to selectively provide L3 level routing or L2 level switching/bridging between different logical interfaces. In some embodiments, the controller selects between configuring the packet engine to perform L3 routing or configuring the packet engine to perform L2 bridging based on whether the packet engine support unnumbered interfaces and integrated routing and bridging (IRB).

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. Upon receiving upstream data packet from a particular cable service flow, the remote distribution node applies a set of tags or labels to the data packet identifying the data packet as being from the particular cable service flow. The remote distribution node then forwards the tagged packet toward the packet engine, where the tags/labels are used to direct the packet toward the corresponding logical interface of the particular cable service flow.

Abstract: A novel method for provisioning network services for a cable system is provided. The method provides a configuration command interpreter/compiler that receives configuration commands of the cable system and generates configuration commands understood by the actual physical devices implementing the cable system. The interpreter transforms the configuration commands of the cable system into the configuration commands of the actual physical devices based on a set of normalized data models describing the cable system. The normalized data models are applicable to the cable system regardless of the actual devices implementing the cable system. The normalized data models are specified using normalized parameters that are generally applicable to different types devices that can be used to implement the cable system.

Abstract: A novel method of handling network traffic for cable service flows in a distributed cable system is presented. Such a cable systems use remote distribution nodes in the fields to handle RF communications with cable modems in a distributed fashion. A packet engine is configured to assign a logical interface to each cable service flow in the cable system. Each logical interface in the packet engine is uniquely identifiable by a compound identifier that includes the identifier of the corresponding service flow and the identifier of the remote distribution node. Each service flow is assigned a class of service (CoS) at the packet engine and guarantee a certain level of quality of service (QoS). In some embodiments, each cable service flow is assigned a CoS priority number. For each possible CoS priority number, the packet engine is configured to provide certain resources at certain quality level, i.e., certain level of QoS.

Abstract: In general, techniques are described for scheduling traffic for delivery over an aggregated bundle of links. A network device comprising an interface and a data plane may implement the techniques. The interface receives packets associated with packet flows. The data plane associates each of the packet flows with a different link of an aggregated bundle of links. The data plane monitors transmission of the packets via the links to determine a representation of an amount of data sent per link. The data plane further determines that bandwidth utilization does not conform to a desired bandwidth utilization based on the determined representation of the amount of data sent per link. The data plane then re-associates the packet flows to different links of the aggregated bundle based on the determination that the bandwidth utilization does not conform to the desired bandwidth utilization.

Abstract: A network device provides a selector list that includes indices of child nexthops associated with the network device, where each of the child nexthops is associated with a corresponding child link provided in an aggregated bundle of child links. The network device also receives an indication of a failure of a child link in the aggregated bundle of child links, and removes, from the selector list, an index of a child nexthop associated with the failed child link. The network device further receives probabilities associated with the child links of the aggregated bundle of child links. Each of the probabilities indicates a probability of a packet exiting the network device on a child link. The network device also creates a distribution table based on the probabilities associated with the child links, and rearranges values provided in the distribution table.

Abstract: Techniques for handling multicast over link aggregated (LAG) interfaces and integrated routing and bridging (IRB) interfaces in a network device are described in which interfaces, at which a data unit is to be transmitted, may be represented hierarchically in which the LAG interfaces and IRB interfaces are represented as pointers. In one implementation, a device may determine routes for data units, where a route for a multicast data unit is represented as a set of interfaces of the device at which the data unit is to be output. Entries in the set of interfaces may include physical interfaces of the device and pointers to LAG interfaces or pointers to the IRB interfaces. The device may generate tokens to represent routes for data units and resolve the pointers to the LAG interfaces or the IRB interfaces to obtain physical interfaces of the router corresponding to a LAG or an IRB.

Abstract: A network device provides a selector list that includes indices of child nexthops associated with the network device, where each of the child nexthops is associated with a corresponding child link provided in an aggregated bundle of child links. The network device also receives an indication of a failure of a child link in the aggregated bundle of child links, and removes, from the selector list, an index of a child nexthop associated with the failed child link. The network device further receives probabilities associated with the child links of the aggregated bundle of child links. Each of the probabilities indicates a probability of a packet exiting the network device on a child link. The network device also creates a distribution table based on the probabilities associated with the child links, and rearranges values provided in the distribution table.

Abstract: A network device provides a selector list that includes indices of child nexthops associated with the network device, where each of the child nexthops is associated with a corresponding child link provided in an aggregated bundle of child links. The network device also receives an indication of a failure of a child link in the aggregated bundle of child links, and removes, from the selector list, an index of a child nexthop associated with the failed child link. The network device further receives probabilities associated with the child links of the aggregated bundle of child links. Each of the probabilities indicates a probability of a packet exiting the network device on a child link. The network device also creates a distribution table based on the probabilities associated with the child links, and rearranges values provided in the distribution table.

Abstract: Techniques for handling multicast over link aggregated (LAG) interfaces and integrated routing and bridging (IRB) interfaces in a network device are described in which interfaces, at which a data unit is to be transmitted, may be represented hierarchically in which the LAG interfaces and IRB interfaces are represented as pointers. In one implementation, a device may determine routes for data units, where a route for a multicast data unit is represented as a set of interfaces of the device at which the data unit is to be output. Entries in the set of interfaces may include physical interfaces of the device and pointers to LAG interfaces or pointers to the IRB interfaces. The device may generate tokens to represent routes for data units and resolve the pointers to the LAG interfaces or the IRB interfaces to obtain physical interfaces of the router corresponding to a LAG or an IRB.

Abstract: A network device provides a selector list that includes indices of child nexthops associated with the network device, where each of the child nexthops is associated with a corresponding child link provided in an aggregated bundle of child links. The network device also receives an indication of a failure of a child link in the aggregated bundle of child links, and removes, from the selector list, an index of a child nexthop associated with the failed child link. The network device further receives probabilities associated with the child links of the aggregated bundle of child links. Each of the probabilities indicates a probability of a packet exiting the network device on a child link. The network device also creates a distribution table based on the probabilities associated with the child links, and rearranges values provided in the distribution table.

Abstract: An embodiment of the invention provides a flexible bandwidth advertisement method that can reduce the number of routing updates that are sent in a network. In an embodiment of the invention, a method of reducing available bandwidth updates in a link in a communication system is provided. The method includes setting a range of threshold values. An actual available bandwidth in the link is then changed. If the actual available bandwidth changes from a first value within the range of threshold values to a second value within the range of threshold values, then a transmission of an available bandwidth update on the link is then prevented.

Abstract: Lines within an aggregated link extending between network elements in a communications system are monitored for faults. Once a fault is detected on a particular line carrying a control channel, an alternative line is selected and control channel is transmitted on the alternative line. Once a control channel is received at a remote end on a new line, the control channel is reassigned to that line. In an alternative embodiment, the control channel is split into separate channels carrying routing and signaling information, respectively. The separate routing and signaling channels are carried by separate lines, but can be reassigned to other lines in response to a fault. Further, the routing information can be carried by multiple lines in an alternating pattern such as a round robin fashion.

Abstract: Lines within an aggregated link extending between network elements in a communications system are monitored for faults. Once a fault is detected on a particular line carrying a control channel, an alternative line is selected and control channel is transmitted on the alternative line. Once a control channel is received at a remote end on a new line, the control channel is reassigned to that line. In an alternative embodiment, the control channel is split into separate channels carrying routing and signaling information, respectively. The separate routing and signaling channels are carried by separate lines, but can be reassigned to other lines in response to a fault. Further, the routing information can be carried by multiple lines in an alternating pattern such as a round robin fashion.