Abstract: In general, techniques are described for mapping WAN conditions to appropriate back-pressure mechanisms at the WAN edges to improve the performance of delay and/or loss-sensitive applications. In one example, a system includes a wide area network having a provider edge (PE) router to establish a Fibre Channel over Ethernet (FCoE) pseudowire over the wide area network. A Lossless Ethernet network attaches, by an attachment circuit, to the FCoE pseudowire at the PE router. A Fibre Channel Fabric connects to the Lossless Ethernet network and to a storage device that provides data for transmission over the wide area network by the FCoE pseudowire. The PE router detects a defect in the FCoE pseudowire and, in response to detecting the defect in FCoE pseudowire, injects an FCoE flow control extension into the Lossless Ethernet network by the attachment circuit.

Abstract: In general, principles of the invention relate to techniques for detecting data plane failures in Multi-Protocol Label Switching (MPLS) Label-Switched Paths (LSPs) that may be tunneled over one or more other LSPs. More specifically, the techniques described herein allow for testing connectivity of an LSP that is tunneled through at least one other LSP, and testing connectivity of an inter-autonomous system LSP. For example, a method comprises providing, with an intermediate label-switching router (LSR) of an LSP, instructions to an ingress LSR of the LSP to modify a forwarding equivalence class (FEC) stack of MPLS echo request packets. The intermediate LSR may provide the instructions within an MPLS echo reply packet.

Abstract: In general, techniques are described for providing extended administrative groups in networks. A network device comprising an interface and a control unit may implement the techniques. The interface receives a routing protocol message that advertises a link. This message includes a field for storing first data associated with the link in accordance with the routing protocol. The field is defined by the routing protocol as a field having a different function from an administrative group field defined by the same routing protocol. The control unit determines that this field has been repurposed to store second data, wherein this second data specifies an extended administrative group for the link different from those that may be specified by the administrative group field. The control unit then updates routing information to associate the advertised link with the extended administrative group and performs path selection to select paths based on the updated routing information.

Abstract: Techniques are described for configuration of a multi-chassis router for managing periodic communications between the multi-chassis router and other network devices. The multi-chassis router selectively processes data received from a network by determine whether the data: (1) indicates an operational state of a network device in association with a routing protocol, or (2) conveys routing information for the routing protocol. Data conveying routing information are processed by a master routing component of the multi-chassis router, while data indicating an operational state of a network device are processed by one or more slave routing components of the multi-chassis router.

Abstract: A method performed by a network device may include assembling a multiprotocol label switching (MPLS) echo request, the echo request including an instruction for a transit node to forward the echo request via a bypass path associated with the transit node, and an instruction for an egress node to send an echo reply indicating that the echo request was received on the bypass path. The method may also include sending the MPLS echo request over a functioning label switched path (LSP).

Abstract: The invention is directed to techniques for failsafe management of periodic communications between network devices. A first network device, for example, establishes with a second network device a first response interval by which the first device responds to a message received from the second device. Prior to commencing a software upgrade, the first device determines whether the event requires an interval of time during which the first device cannot respond to the message within the established first response interval. Based on the determination and prior to commencing the upgrade, the first device establishes with the second device a second response interval that equals or exceeds the first response interval. Upon completion of the event, the first device establishes with the second device a third response interval. The first network device therefore may automatically adjust response intervals to accommodate upgrades that may cause unnecessary thrashing.

Abstract: In general, principles of the invention relate to techniques for detecting data plane failures in Multi-Protocol Label Switching (MPLS) Label-Switched Paths (LSPs) that may be tunneled over one or more other LSPs. More specifically, the techniques described herein allow for testing connectivity of an LSP that is tunneled through at least one other LSP, and testing connectivity of an inter-autonomous system LSP. For example, a method comprises providing, with an intermediate label-switching router (LSR) of an LSP, instructions to an ingress LSR of the LSP to modify a forwarding equivalence class (FEC) stack of MPLS echo request packets. The intermediate LSR may provide the instructions within an MPLS echo reply packet.

Abstract: A method performed by a network device may include assembling a multiprotocol label switching (MPLS) echo request, the echo request including an instruction for a transit node to forward the echo request via a bypass path associated with the transit node, and an instruction for an egress node to send an echo reply indicating that the echo request was received on the bypass path. The method may also include sending the MPLS echo request over a functioning label switched path (LSP).

Abstract: Techniques are described for configuration of a multi-chassis router for managing periodic communications between the multi-chassis router and other network devices. The multi-chassis router selectively processes data received from a network by determine whether the data: (1) indicates an operational state of a network device in association with a routing protocol, or (2) conveys routing information for the routing protocol. Data conveying routing information are processed by a master routing component of the multi-chassis router, while data indicating an operational state of a network device are processed by one or more slave routing components of the multi-chassis router.