Abstract: Apparatus, and an associated method, for facilitating performance of multi-media, and other communication, services at an Ethernet network. A bridge provides communication control operations at the Ethernet network. Audio-video bridge domains are defined at the network. Service discovery messages generated by communication devices of a particular domain are forwarded only to other communication devices of the same domain. Redefinition and reconfiguration of the domains is made, as needed, all best to facilitate performance of the communication service.

Abstract: A bridged network system (10, 10?) is described comprising a plurality of nodes (N1-N7). Each node in the plurality of nodes is coupled to communicate with at least one other node in the plurality of nodes. The plurality of nodes comprise a bridge network between external nodes located externally from the plurality of nodes. Each node of the plurality of nodes is operable to perform the steps of receiving a packet (20, 20?), wherein the packet comprises a route indicator field, and responsive to the packet being received prior to a time of failure along a communication link between two of the plurality of nodes, transmitting the packet along a first route in the system to another node in the plurality of nodes.

Abstract: Customer virtual local area networks (C-VLANs) connecting multiple LAN segments are set up through a provider network (12). Provider edge bridges (PEs) are coupled to customer edge bridges (CEs) to provide a transparent link between LAN segments. To determine whether a backdoor link is used in the C-VLAN topology, PEs monitor MAC address from a predetermined time after a TCN is received to determine if there are contradictory addresses or new addresses relative to the existing MAC address tables (or forwarding databases) that are indicative of a backdoor link. If so, an unlearning message is sent to bridges in the provider domain. In another embodiment, CEs set a snoop bit to indicate which TCNs must be snooped.

Abstract: A system and method for securing an Ethernet Connectivity Fault Management (CFM) domain defined on a Virtual Local Area Network (VLAN). In one embodiment, the scheme includes, responsive to registering by an external port with the VLAN, whereby the VLAN is extended to include the external port, monitoring by a boundary Maintenance End Point (MEP) node of the Ethernet CFM domain to determine if bidirectional control frame flow (e.g., Continuity Check (CC) frame flow) is observed thereat; and, responsive to determining by the boundary MEP node that there is no bidirectional control frame flow therethrough, generating an alarm indicative of a potential breach of the Ethernet CFM domain by the external port.

Abstract: A bridge (e.g., IEEE 802.1 bridge) and a method are described herein which ensure the proper propagation of a “cut” within a bridged network (e.g., Ethernet-based bridged network). In one embodiment, the bridge has a port role transitions (PRT) state machine which uses a first condition represented as (proposed && !agree) to transit to an X_PROPOSED state and a second condition represented as (! proposed && allSynced && !agree) ? (proposed && agree) to transit to an X_AGREED state (where X represents “ROOT”, “ALTERNATE” and “MASTER”). The first condition and the second condition are both defined such that the X_PROPOSED state is always entered before the X_AGREED state which ensures the proper propagation of a “cut” within the bridged network.

Abstract: Apparatus, and an associated method, for facilitating performance of multi-media, and other communication, services at an Ethernet network. A bridge provides communication control operations at the Ethernet network. Audio-video bridge domains are defined at the network. Service discovery messages generated by communication devices of a particular domain are forwarded only to other communication devices of the same domain. Redefinition and reconfiguration of the domains is made, as needed, all best to facilitate performance of the communication service.

Abstract: A bridged network system (20). The bridged network system comprises a plurality of bridge nodes (N0-N7). Each bridge node in the plurality of bridge nodes is coupled to communicate with at least one other bridge node in the plurality of nodes. Further, bridge nodes in the plurality of bridge nodes are connected to one another to form a communications-possible line of bridge nodes (N0, N7, N6, N5, N1, N4, N3, N2). Each bridge node comprises circuitry for associating a bridge priority, selected from a plurality of bridge priorities, with the respective bridge node. The plurality of bridge priorities may be arranged in an ordered sequence, but the bridge priorities associated with successive bridge nodes along the communications-possible line of bridge nodes comprises at least two discontinuities (N0/N7; N1/N5; N1/N4) in the ordered sequence.

Abstract: A bridge (e.g., IEEE 802.1 bridge) and a method are described herein which ensure the proper propagation of a “cut” within a bridged network (e.g., Ethernet-based bridged network). In one embodiment, the bridge has a port role transitions (PRT) state machine which uses a first condition represented as (proposed && !agree) to transit to an X_PROPOSED state and a second condition represented as (! proposed && allSynced && !agree) ? (proposed && agree) to transit to an X_AGREED state (where X represents “ROOT”, “ALTERNATE” and “MASTER”). The first condition and the second condition are both defined such that the X_PROPOSED state is always entered before the X_AGREED state which ensures the proper propagation of a “cut” within the bridged network.

Abstract: System and method for diagnosing misconfigurations in a network are described. In one embodiment, the method comprises querying a network element for a current value of at least one parameter; determining an optimal value of the at least one parameter; comparing the current value of the at least one parameter with the optimal value of the at least one parameter; and providing a notification if a discrepancy exists between the optimal value of the at least one parameter and the current value of the at least one parameter.

Abstract: System and method for providing fast protection in a passive optical network (“PON”) including two central hubs and a plurality of network nodes, wherein the network nodes are connected to a first of the central hubs by a first optical path and to a second of the central hubs by a second optical path. The method comprises setting the first and second central hubs to master mode and slave mode, respectively, such that only the first central hub transmits traffic to and from the network nodes; detecting a failure in the first optical path; exchanging status information between the first and second central hubs; and if no failure has occurred in the second optical path, setting the first and second central hubs to slave mode and master mode, respectively, such that only the second central hub transmits traffic to and from the network nodes.

Abstract: A bridged network system (20). The bridged network system comprises a plurality of bridge nodes (N0-N7). Each bridge node in the plurality of bridge nodes is coupled to communicate with at least one other bridge node in the plurality of nodes. Further, bridge nodes in the plurality of bridge nodes are connected to one another to form a communications-possible line of bridge nodes (N0, N7, N6, N5, N1, N4, N3, N2). Each bridge node comprises circuitry for associating a bridge priority, selected from a plurality of bridge priorities, with the respective bridge node. The plurality of bridge priorities may be arranged in an ordered sequence, but the bridge priorities associated with successive bridge nodes along the communications-possible line of bridge nodes comprises at least two discontinuities (N0/N7; N1/N5; N1/N4) in the ordered sequence.

Abstract: A system and method for securing an Ethernet Connectivity Fault Management (CFM) domain defined on a Virtual Local Area Network (VLAN). In one embodiment, the scheme includes, responsive to registering by an external port with the VLAN, whereby the VLAN is extended to include the external port, monitoring by a boundary Maintenance End Point (MEP) node of the Ethernet CFM domain to determine if bidirectional control frame flow (e.g., Continuity Check (CC) frame flow) is observed thereat; and, responsive to determining by the boundary MEP node that there is no bidirectional control frame flow therethrough, generating an alarm indicative of a potential breach of the Ethernet CFM domain by the external port.

Abstract: A method is described herein for configuring a computer network managed by the IEEE Std 802.1s™-2002 MSTP standard or any other equivalent standard such as IEEE Std 802.1Q™-2003 in a fully- or semi-automatic manner such that: (1) if at all possible and in the case of a failure in the MSTP-based computer network affecting a Multiple Spanning Tree Instance (MSTI), MSTP reestablishes connectivity in that MSTI by preferably activating links whose activation ensures that the connectivity within a Virtual Local Area Network (VLAN) mapped onto and associated with that MSTI is not lost; and (2) a VLAN is mapped onto a MSTI whose active topology covers the topology of this VLAN, this being ensured by setting up that MSTI depending on the desired VLAN topology.

Abstract: A network (e.g., RSTP-based network) and method are described herein that can selectively eliminate latencies in the exchange of to-be-transmitted control messages (e.g., BPDUs) between bridges during the re/convergence of the network. The method includes a step of classifying to-be-transmitted control messages as either low-priority control messages or high-priority control messages. The method also has a step of limiting the transmission rate of the low-priority control messages in accordance with a traditional IEEE 802.1 RSTP. And, the method also includes a step of immediately transmitting the high-priority control messages that contain information that contributes to the re/convergence of the network.

Abstract: Customer virtual local area networks (C-VLANs) connecting multiple LAN segments are set up through a provider network (12). Provider edge bridges (PEs) are coupled to customer edge bridges (CEs) to provide a transparent link between LAN segments. To determine whether a backdoor link is used in the C-VLAN topology, PEs monitor MAC address from a predetermined time after a TCN is received to determine if there are contradictory addresses or new addresses relative to the existing MAC address tables (or forwarding databases) that are indicative of a backdoor link. If so, an unlearning message is sent to bridges in the provider domain. In another embodiment, CEs set a snoop bit to indicate which TCNs must be snooped.