Abstract: A method of controlling traffic forwarding in a Provider Backbone-Traffic Engineered (PBB-TE) network. A protection group (PG) is defined, and including N working Traffic Engineered Service Instances (TESIs) and M protection TESIs. An Automatic Protection Switching Protocol Data Unit (APS PDU) is defined, which includes information defining at least a state of the protection group. This APS PDU is forwarded only through the protection TESI(s).

Abstract: Protection switching in an Ethernet packet-switched network includes establishing first and second virtual circuits. The first virtual circuit carries packet traffic associated with a different service instance from packet traffic carried by the second virtual circuit. Packet traffic of the first virtual circuit is transmitted from a source network element to a sink network element through a first Ethernet tunnel. Packet traffic of the second virtual circuit is transmitted from the same source network element to the same sink network element through a second Ethernet tunnel. The second Ethernet tunnel is a different path through the Ethernet packet-switched network from the first Ethernet tunnel. During a protection switch, the first virtual circuit is switched from the first Ethernet tunnel to the second Ethernet tunnel. After the switch, packet traffic of the first virtual circuit and packet traffic of the second virtual circuit are transmitted over the second Ethernet tunnel.

Abstract: An optical network and method for managing a service across an optical network over a dedicated circuit between first and second service termination points include generating a service performance report message (PRM) at each service termination point. Each service PRM has service-specific information related to a performance of the service as determined by the service termination point generating that service PRM. Each service PRM identifies the service to which the service-specific information in that service PRM pertains. Each service termination point transmits the service PRM generated by that service termination point across the optical network over the dedicated circuit to the other service termination point through a service management channel of an optical transport facility.

Abstract: Interworking an Ethernet Ring network with an Ethernet network with traffic engineered trunks (PBT network) enables traffic engineered trunks to be dual homed to the Ethernet ring network to enable for protection switching between active and backup trunk paths in the PBT network. In one embodiment, the active path will terminate at a first bridge node on the Ethernet ring network and the backup path will terminate at a second bridge node on the Ethernet ring network. Trunk state information is exchanged between the bridge nodes to enable the bridge nodes to determine which of the active and backup paths should be used to forward data on the trunk. Upon a change in trunk state, a flush message is transmitted on the Ethernet ring network to enable the nodes on the Ethernet ring network to relearn the path to the new responsible bridge node.

Abstract: To enable an Ethernet ring to be dual homed into a spanning tree protocol controlled Ethernet network, spanning tree control packets (Bridged Protocol Data Units or BPDUs) are transported as data frames over the Ethernet ring. This allows the Ethernet ring to appear as a single link to the spanning tree protocol so that the spanning tree can extend over the link. However, since the spanning tree does not have visibility as to the internal structure of the ring, the spanning tree cannot block links on the Ethernet ring network. Conversely, BPDUs from the Ethernet ring are not transmitted into the Ethernet domain that is implementing the spanning tree, so that the spanning tree is not affected by the control mechanism in place on the Ethernet ring network.

Abstract: Described are a system and method for managing a service across an optical network over a dedicated circuit between a first and second service termination points. Each service termination point generates a service performance report message. Each service performance report messages has information related to a performance of the service as determined by the service termination point generating the message. The service termination points exchange the service performance report messages over a service management channel to enable an assessment of the performance of the service based on the service performance report messages from both service termination points. Through access to and use of the service management channel, service providers can implement an edge management model or a core management model for measuring the performance of their services with respect to service level agreements governing those services.

Abstract: A resilient virtual Ethernet ring has nodes interconnected by working and protection paths. If a span fails, the two nodes immediately on either side of the failure are cross-connected to fold the ring. Working-path traffic is cross-connected onto the protection path at the first of the two nodes and is then cross-connected back onto the working path at the second of the two nodes so that traffic always ingresses and egresses the ring from the working path. A traffic originating node, upon determining that transmitted packets are being looped back due to a fault on a primary path, is adapted to switch transmission of data packets from the primary path to a secondary path.

Abstract: A method and system for protecting a service available on a broadcast domain. A sub-domain is established within the broadcast domain. The sub-domain includes a group of nodes used to provide a communication path to the service. A primary sub-domain maintenance association and a back-up sub-domain maintenance association are monitored. The primary and sub-domain maintenance associations are a set of primary and back-up paths, respectively, representing connectivity between nodes acting as edge nodes in the sub-domain. A fault is detected within the primary sub-domain maintenance association and a switch to the back-up sub-domain maintenance association occurs.

Abstract: An Ethernet virtual switched sub-network (VSS) is implemented as a virtual hub and spoke architecture overlaid on hub and spoke connectivity built of a combination of Provider Backbone Transport (spokes) and a provider backbone bridged sub-network (hub). Multiple VSS instances are multiplexed over top of the PBT/PBB infrastructure. A loop free resilient Ethernet carrier network is provided by interconnecting Provider Edge nodes through access sub-networks to Provider Tandems to form Provider Backbone Transports spokes with a distributed switch architecture of the Provider Backbone Bridged hub sub-network. Provider Backbone transport protection groups may be formed from the Provider Edge to diversely homed Provider Tandems by defining working and protection trunks through the access sub-network.

Abstract: A system, method and/or station that provides for spatial reuse over a resilient packet ring (RPR) network. A sublayer in a station on an RPR network tracks associations between MAC addresses of bridges on the RPR network and remote addresses in an association database. Frames addressed to a remote destination may be sent directly to the associated MAC address. A sending station uses an extended frame format for sending frames to remote addresses. If the association database in the sending station specifies an associated bridge MAC address local to the RPR network then the extended frame is addressed to the specified MAC address and flooding is disabled. If there is no association in the database, then the sending station uses a reserved group address and floods the RPR network. The sublayer “learns” associations based upon frames received from stations that also have a spatially aware sublayer.

Abstract: Connectivity fault notification is provided by generating an alarm indication signal at a device that is logically adjacent to the fault, and forwarding the alarm indication signal upward through various levels to at least one client level entity. The alarm indication signal may be suppressed at any level for a service instance if service is restored at that level, or if a protection path prevents disruption of the service instance at that level, or auto-suppressed at an originating node based on number of times transmitted or elapsed time. The alarm indication signal may include a point of failure indicator such as the MAC address of the device that generates the alarm indication signal, or a failed resource identity such as an IEEE 802.1AB LLDP MAC Service Access Point (“MSAP”). Further, the alarm indication signal may be employed to trigger use of the protection path.

Abstract: An edge device is used to support a backbone provider bridging network to facilitate interconnection of a plurality of networks. The edge device is coupled between the backbone and a first one of the networks, and is operable to encapsulate data units received from the first network with a header, and to forward the encapsulated data unit to the backbone. The header is indicative of a tunnel that is used to support traffic from the first network to a second network over the backbone. The edge device also de-encapsulates data units received from the backbone that are destined for the first network.

Abstract: Network topography may be discovered by a network element on an Ethernet network by collecting connectivity check messages periodically issued by other network elements on the network and using the information gleaned from those messages to build a topography database. Since the connectivity check messages may be link level or service instance based, the topography database may include network topography as well as service topography on the Ethernet network. Ethernet OAM loopback frames may also be used to cause network elements on the Ethernet network to issue response frames directed to the initiating network element. By collecting responses from the responding network elements, the initiating network element can build a topography database of network elements on the Ethernet network. This topography database may show the overall network topography or service instances on the network, and may provide visibility within one or more domains.

Abstract: Maintenance entities may be defined between customer and provider flow points to allow performance management to take place on an Ethernet network. The maintenance entities may be defined for access link, intra-domain, and inter-domain, and may be defined on a link or service basis. The maintenance entities may be used to monitor performance within a network or across networks, and may be used to monitor various performance parameters, such as frame loss, frame delay, frame delay variation, availability, errored frame seconds, service status, frame throughput, the number of frames transmitted, received or dropped, the status of a loopback interface, the amount of time a service has been unavailable, and many other parameters. Several management mechanisms may be used, and the measurements may be collected using a solicited collection method, in which a responses are required and collected, or an unsolicited collection method in which a response is not required.

Abstract: Ethernet OAM may be used to trace a path on an Ethernet network. If the path reaches the destination, there is no fault. If the path doesn't reach the destination, the network element farthest along the path is adjacent the fault. The path trace may be used from both ends of a given path to confirm the presence of a single fault or to determine the likelihood of multiple faults on the path. A path trace Ethernet OAM frame may be issued on the network with instructions that network elements with knowledge of a destination address should respond. If a network element knows the destination address, the receiving network element responds to the initiating network element with a unicast OAM frame and forwards the OAM frame if possible. The sequence of unicast response frames allows the initiating network element to build a path through the network toward the destination element and identify where the path stops.

Abstract: Ethernet OAM domains may be defined by defining reference points on the Ethernet network and using the reference points to insert and extract Ethernet OAM flows. The reference points may be network elements at the edge of a provider's domain, customer elements, or network elements configured to perform OAM flow handoffs between domains. By defining OAM multicast addresses and OAM flow identifiers, and allowing the reference points to be addressed by the multicast address and filtering to be performed by the reference points based on the OAM flow identifiers, OAM flows may be defined on the network. For example, customer-customer OAM flows may be defined, intra-provider and inter-provider OAM flows may be defined, and various segment OAM flows may be defined. An OAM frame format is provided to enable the OAM flows to be carried in a conventional Ethernet network.

Abstract: Ethernet OAM connectivity check may be used to detect connectivity failures across a given pair of network elements on an Ethernet network. Connectivity check frames are generated and sent to a specific unicast DA or to a multicast DA. Once a network element begins to receive connectivity check frames, it expects to continue to receive further periodic connectivity check frames from that network element. If the network element stops receiving periodic connectivity check frames, it detects that connectivity to the sending network element is broken. Once a fault is identified, the fault may be verified using a loopback function, which causes a network element receiving an Ethernet frame to transmit a corresponding frame back to the original network element. Loopback may be intrusive such that all received frames are looped back except OAM frames, or non-intrusive where only OAM frames are looped back.

Abstract: Described are a system and method for managing a service transported over a transport network. Service traffic is transmitted from a first network element to a second network element over a transport network. If one of the network elements detects a condition occurring in the transport network, the network element determines each service affected by the condition. Service traffic performance is measured at each of the first and second network elements. Each network element correlates its measure service traffic performance and the service to produce a performance of service (PoS) service metric. Each network element transmits its measured PoS service metric to the other network element over a service management channel. This enables each network element to correlate both performance (SPC) and fault (SFC) for both near and far end service metrics and enables a complete end to end service definition in support of a service level agreement (SLA).

Abstract: Described are a system and method for identifying private resources associated with a communications network. A structured address format is defined having a plurality of character positions. Each character position is associated generally with a property of a managed resource in the communications network. A structured private address, constructed according to the structured address format, is assigned to the managed resource. Each character position of the assigned structured address has a value that identifies a specific instance of the property of the managed resource associated with that character position. Operations Systems Support (OSS) gives a common name to the managed resource and maintains an association between the common name and the structured address. The structured address format can follow a four-byte dotted decimal notation similar to IPv4 addresses.

Abstract: Described are a system and method for managing a service transported over a transport network between first and second service termination points. Packet traffic associated with the service is received at a service termination point connected to the transport network. Performance of the packet traffic is measured at the service termination point. The measured performance of the packet traffic and the service are correlated to produce a performance of service (PoS) service metric. Based on the PoS service metric, other service metrics associated with the service are correlated, including a rate of service (RoS) service metric and availability of service (AoS) service metric. These service metrics can be used to develop service level agreement (SLA) and service level metrics that define the operation of the service and operation of the network supporting those services.