A method and a first device (110) of a switched network (100), for managing data frames received, at a first port, from a second device (120) are disclosed. The first device (110) handles the first port and a second port for transfer of data frames between the first and second devices (110, 120). The first device (110) is addressable by a Media Access Control address, “MAC address”, associated with the first port. The first device (110) receives (201), from the second device (120), at least one data frame at the second port. The first device (110) sends (202), on the first port, a message including the MAC address associated with the first port.

Disclosed are an airplane system including duplex modules, and a control method thereof. The control method of the airplane system includes: receiving, by each of a plurality of duplex modules, a corresponding event command from a client; performing, by a first module, a first event specified by the event command in response to the event command; performing, by a second module different from the first module, a second event specified by the event command after the first event is completed; and returning a first response signal indicating a result of the performance of the first event and a second response signal indicating a result of the performance of the second event to the client, in which the client compares the first response signal and the second response signal, and determines whether the plurality of duplex modules is synchronized or has an error.

The invention relates to network nodes comprising: a first computing unit (CPU.sub.a); at least one second computing unit (CPU.sub.b); an internal switch (Sw.sub.i); and an external switch (Sw.sub.e), wherein the internal switch (Sw.sub.i) is connected to the first computing Nunit (CPU.sub.a), the at least second computing unit (CPU.sub.b) and to the external switch (Sw.sub.e) and wherein the external switch (Sw.sub.e) has at least one port for data originating from other network nodes. The invention also relates to a control module and an Ethernet ring.

Traffic recovery is supported at a switching node (20) of an OpenFlow network (5). The switching node (20) has a flow table (23) for storing flow entries (24) which determine forwarding of received packets between the ports. A switching node (20) installs (102) a flow entry for a back up path in the flow table (23). The switching node (20) renews (104, 105) the flow entry for the backup path based on at least one of: (i) an association between the flow entry for the backup path and a flow entry for a working path at the switching node, wherein the flow entry for the backup path is renewed when the flow entry for the working path is used to forward a received packet; (ii) receiving a flow entry renewal packet from another switching node on the backup path. A backup path can be configured for each of multiple points of failure in the working path.

There is provided a system and method for resilient routing based on a multi-channel model for emergency management. The system includes a packet delivery anomaly detector for determining an existence of an anomaly in a mandated routing infrastructure for a packet that renders the packet incapable of reaching a destination node designated for the packet through the mandated routing infrastructure. The system further includes a dynamic alternate route identifier for dynamically identifying alternate routes for the packet responsive to a determination of the existence of the anomaly. The alternate routes are outside the mandated routing infrastructure, are provided using one or more mobile devices external to and not part of the mandated routing infrastructure, and are dynamically identified responsive to at least geographic location information. The system also includes a wireless transmitter for wirelessly routing the packet using at least one of the alternate routes.

In one embodiment, a source transmits one or more data packets to a destination over a primary pseudowire (PW). When a device on the primary PW detects a downstream failure of the primary PW, and in response to receiving one or more data packets from a source from the failed primary PW, the device adds a loopback packet identifier to the one or more received data packets, and returns the one or more data packets with the loopback packet identifier to the source upstream on the primary PW. Accordingly, in response to receiving the data packet returned with a loopback packet identifier from the primary PW (in response to the downstream failure), the source retransmits the one or more data packets to the destination over a backup PW.

A switching method includes receiving a failure notification through each of two or more paths included in a plurality of paths; by referring to path management information in which a group and a combination of a plurality of predetermined paths are associated with each other for each of a plurality of groups generated by grouping the plurality of paths according to a combination of an initial point and an end point, determining, for each of the plurality of groups, whether a combination of paths through which the failure notification is received matches with the combination of the plurality of predetermined paths; and switching a path included in an object group corresponding to the two or more paths from an active system to a standby system, when it is determined that the combination of the two or more paths matches with the combination of the plurality of predetermined paths.

In one embodiment, a primary tunnel is established from a head-end node to a destination along a path including one or more protected network elements for which a fast reroute path is available to pass traffic around the one or more network elements in the event of their failure. A first path quality measures path quality prior to failure of the one or more protected network elements. A second path quality measures path quality subsequent to failure of the one or more protected network elements, while the fast reroute path is being used to pass traffic of the primary tunnel. A determination is made whether to reestablish the primary tunnel over a new path that does not include the one or more failed protected network elements, or to continue to utilize the path with the fast reroute path, in response to a difference between the first path quality and the second path quality.

A label switched path through a network of nodes, is torn down by sending a message along the path from an ingress node. If there is a fault along the path, a path error message (2) is sent back along the path to the ingress node. The ingress node uses a different route bypassing the fault to alert (3) a further one of the nodes (NE5, NE6) on that path beyond the indicated fault, to cause that further node to continue the tearing down for other nodes on that path beyond the indicated fault by sending a further message (4) along the portion of the path beyond the indicated fault, to indicate to the other nodes to continue the tear down. This enables the ingress node to clean up the rest of the path beyond the fault, to avoid leaving unused capacity unavailable for reuse, and to avoid time consuming manual clean up.

Example embodiments relate to a method of, and device for facilitating, resilient peer-to-peer application message routing. The method comprises storing a network routing table comprising destination addresses of applications hosted on peer nodes of a network, and providing the peer nodes with a copy of the routing table via which routing table an application message from any one of the peer nodes is routed to a destination address designating a destination application hosted by a destination peer node. Further, the method comprises providing, when the destination application hosted by the destination peer node is inactivated, all peer nodes with a copy of an updated routing table taking into account the inactivation of said application, wherein a further application message addressed from any one of the peer nodes to the destination address associated with the inactivated application is routed via the updated routing table, to an alternative destination application having the same destination address as the inactivated application.