Patent application number | Description | Published |
20080267198 | Support of C-tagged service interface in an IEEE 802.1ah bridge - In one embodiment, a Provider Backbone Edge Bridge (BEB) IEEE 802.1ah compliant apparatus includes a B-component having one or more provider backbone ports, and a first I-component coupled with the B-component, the first I-component being configured to support a S-tagged interface. A second I-component is also coupled with the B-component, the second I-component being configured to support a C-tagged interface, thereby facilitating direct connection to a device operating in compliance with IEEE 802.1Q specification. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. | 10-30-2008 |
20080285466 | Interworking between MPLS/IP and Ethernet OAM mechanisms - In one embodiment, a method includes receiving, by a provider edge (PE) device, a transport layer status message indicative of a defect on a pseudowire (PW) running across a core of a service provider (SP) network. The status message is translated to a service layer message indicative of the defect. The service layer message is then transmitted across an access domain of the SP network. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. | 11-20-2008 |
20090016365 | Intra-domain and inter-domain bridging over MPLS using MAC distribution via border gateway protocol - In one embodiment, a method includes receiving, by a first autonomous system border router (ASBR) of a first autonomous system (AS), a first plurality of provider-provisioned media access control (B-MAC) addresses via Interior Border Gateway Protocol (I-BGP). Each of first plurality of B-MAC addresses is associated with a provider edge (PE) device of the first AS. The first ASBR sends the first plurality of B-MAC addresses to a second ASBR of a second AS using Exterior Border Gateway Protocol (E-BGP). The first ASBR also receives via E-BGP a second plurality of B-MAC addresses each of which is associated with a PE device of the second AS. The first ASBR then distributes the second plurality of B-MAC addresses to each of the PE devices of the first AS using I-BGP. | 01-15-2009 |
20090034413 | Redundancy for point-to-multipoint and multipoint-to-multipoint ethernet virtual connections - A method and system for redundancy in Ethernet Virtual Connections (EVCs) are disclosed. In one embodiment, a method includes transmitting continuity check messages from a node in an Ethernet Virtual Connection connecting at least one root node and a plurality of leaf nodes in a point-to-multipoint or multipoint-to-multipoint connection, identifying a failure in a primary path between the root node and the leaf nodes, switching to a backup path, and advertising the switching to the backup path to at least one node. | 02-05-2009 |
20090041038 | Scalable Virtual Private Local Area Network Service - In one embodiment, a method includes receiving a data link layer packet, such as an Ethernet packet, at a local provider edge node in a provider network from a first customer edge node of multiple customer edge nodes connected directly to the local provider edge node. A tunnel data packet for a particular tunneling protocol is generated. The tunnel data packet includes tunnel data that indicates tunnel termination at a different provider edge in the provider network. The tunnel data packet also includes customer identifier data and the data link layer packet. The customer identifier data uniquely indicates a customer associated with the first customer edge node. The tunnel data packet is sent over the provider network. | 02-12-2009 |
20090073989 | Redundancy at a Virtual Provider Edge Node that faces a Tunneling Protocol Core Network for Virtual Private Local Area Network (LAN) Service (VPLS) - In one embodiment, a method includes receiving configuration data at a particular node of a first set of multiple nodes. The configuration data includes data that indicates a particular zero or more instances for which the particular node is primary among multiple virtual local area network (VLAN) instances to be forwarded. It is determined whether a VLAN indicated in a data packet received at the particular node is included in the particular instances for which the particular node is primary. If so, then the data packet is forwarded. In another embodiment, multiple nodes are configured to perform as a single virtual node, and the single virtual node is configured to forward data packets for the multiple VLAN. | 03-19-2009 |
20090122732 | Half-duplex multicast distribution tree construction - In one embodiment, a method includes sending upstream to a nearest neighbor node, by a Client Label Switched Router (LSR), a downstream label map message of a Server-Forwarding Equivalence Class type (S-FEC-DOWN). In response to the S-FEC-DOWN, a downstream forwarding state from the nearest neighbor node to the Client LSR is established. An upstream label map message of a Client-Forwarding Equivalence Class type (C-FEC UP) is received from the nearest neighbor node. An upstream forwarding state corresponding to the C-FEC UP is then established by the Client LSR. | 05-14-2009 |
20090144403 | MANAGEMENT OF TOPOLOGY CHANGES IN LAYER TWO NETWORKS - In one embodiment, a method for managing topology changes in a Layer 2 network is provided. The method may comprise receiving a change notification at a provider edge bridging device and associating the change notification with a customer service. The method may further comprise identifying at least one destination provider edge bridging device associated with the customer service, encapsulating the change notification in a data frame and tunnelling the data frame over a tunnel comprising at least one core device to the at least one destination provider edge bridging device associated with the customer service, the at least one core bridging device tunnelling the data frame based on information relating to the destination provider edge bridging device. | 06-04-2009 |
20090190504 | Multiple I-service registration protocol (MIRP) - In one embodiment, a method associated with a multiple I-service registration protocol (MIRP) includes receiving into an 802.1ah I-component an MVRP TCN from an 802.1ad component. The TCN may be received, for example, from an 802.1ad bridge. The TCN may identify an affected service using an S-VID. Therefore, the example method may include identifying the S-VID specified by the TCN. The method may also include identifying I-SIDs related to the S-VID. The I-SIDs may be identified by consulting an S-VID to I-SID translation table associated with the 802.1ah I-component. The method may also include providing an 802.1ah MIRP PDU to another 802.1ah component. The MIRP PDU may be based on the MVRP TCN and on the I-SID. | 07-30-2009 |
20090196298 | Transportation of IEEE 802.1ah Frames over Multiprotocol Label Switching Pseudowires for Virtual Private LAN Services - Disclosed are, inter alia, methods, apparatus, computer-storage media, mechanisms, and means for transportation of IEEE 802.1 | 08-06-2009 |
20090268731 | Point-to -multipoint for multicast and unicast forwarding - A method and apparatus for establishing multicast and unicast forwarding are disclosed. In one embodiment, a method includes transmitting path messages to a plurality of receivers, receiving a plurality of messages in response to the path messages and establishing unicast and multicast forwarding based on received unicast and multicast labels. Each of the receivers is associated with a sub-LSP (Label Switched Path) in a Point-to-Multipoint (P2MP) LSP and the response messages include a multicast label and at least one unicast label corresponding to a unicast path to one of the receivers. | 10-29-2009 |
20100020680 | MULTI-CHASSIS ETHERNET LINK AGGREGATION - In one embodiment a method is provided for forwarding traffic through a standby device in the event of an uplink connection failure. The method generally includes forwarding traffic received on a first downlink connection with a dual-homed device to an uplink connection with a network core, detecting a failure on the uplink connection with the network core, and in response to detecting the failure, notifying a standby device of the failure and sending a message to the dual-homed device to trigger the dual-homed device to begin forwarding traffic to the network core via a second downlink connection between the standby device and the dual-homed device. | 01-28-2010 |
20100061379 | SYSTEM AND METHOD FOR PROVIDING SUPPORT FOR MULTIPOINT L2VPN SERVICES IN DEVICES WITHOUT LOCAL BRIDGING - A network device has a network interface to allow the device to send and receive traffic across a network. The device also has a cable connection to allow the device to exchange data with at least one cable modem and a processor to associate a cable interface and cable service identifier with a cable modem; receive a packet from the cable modem; and insert a layer 2 network identifier, the identifier comprising two service provider VLAN (SP-VLAN) tags, into the packet. The processor in the network device identifies a virtual trunk interface based on the outer SP-VLAN tag and identifies the virtual private network based on the inner SP-VLAN tag. | 03-11-2010 |
20100157793 | PROVIDER EDGE-CONTROLLED REDUNDANCY USING PSEUDO LINK AGGREGATION CONTROL PROTOCOL - In one embodiment, a system comprises a plurality of provider edge (PE) devices, the PE devices having a plurality of ports; and a pseudo-link aggregation control protocol (LACP) module instantiated for each of the ports. The pseudo-LACP module allows the PE devices to support dual-homing of an access side, the access side including either an access node or an access network, without running any control protocol for redundancy on the access side. | 06-24-2010 |
20100158024 | OPTIMIZED FORWARDING FOR PROVIDER BACKBONE BRIDGES WITH BOTH I&B COMPONENTS (IB-PBB) - In one embodiment, when a frame is directed to one or more customer instance ports (CIPs) of a switch having received the frame, the frame (a “local frame”) may be forwarded on the one or more CIPs based on only a customer space (C-space) lookup operation. Also, if the frame is not directed to any CIPs of the switch, the frame (a “transient frame”) may be forwarded on at least one or more provider backbone ports (PBPs) of the switch based on only a backbone space (B-space) lookup operation. For example, a unicast frame may be forwarded based on whether the frame terminates at the switch having received the frame (to a CIP of the switch), while a multicast frame may be forwarded based on determining whether an instance service identifier (I-SID) of the frame maps to a local VLAN ID (L-VID) at the switch (to any CIPs servicing that L-VID). | 06-24-2010 |
20100238808 | CONNECTIVITY FAULT MANAGEMENT (CFM) AUTO-PROVISIONING USING VIRTUAL PRIVATE LAN SERVICE (VPLS) AUTO-DISCOVERY - Connectivity Fault Management (CFM) auto-provisioning using Virtual Private LAN Service (VPLS) auto-discovery is described. In one embodiment, an apparatus comprises VPLS logic and configuration logic. The VPLS logic is operable at least to receive and send configuration information for a VPLS instance, where the configuration information comprises: a first value that uniquely identifies the VPLS instance; and a plurality of second values that respectively and uniquely identify a plurality of network elements that are operable to provide the VPLS instance. The configuration logic is operable at least to automatically configure, based on the first value and on the plurality of second values, a CFM association and a local maintenance endpoint (MEP) for the VPLS instance on the apparatus. | 09-23-2010 |
20100315946 | Failure protection for access ring topology - In one embodiment, a method includes configuring a first node, located at an edge of a core network and connected to an access ring, with a maintenance end point for a virtual local area network on a port connecting the first node to the access ring. The first node operates in an active mode for the virtual local area network and is in communication with a second node located at the edge of the core network and connected to the access ring. The method further includes receiving and processing at a processor at the first node, continuity check messages from access nodes on the access ring, synchronizing the first node with the second node, and communicating from the first node to the second node to initiate switching of the second node from a backup mode to the active mode for the virtual local area network upon identification of a failure. | 12-16-2010 |
20110032945 | SIGNALING OF ATTACHMENT CIRCUIT STATUS AND AUTOMATIC DISCOVERY OF INTER-CHASSIS COMMUNICATION PEERS - In an embodiment, a method of signaling status at a routing device is provided. In this method, the routing device establishes an inter-chassis control plane channel session with a remote routing device. Here, the routing device and the remote routing device are linked to a multi-homed routing device. The routing device then synchronizes with the remote routing device by way of the inter-chassis control plane channel session to identify a state of a link from the routing device to the multi-homed routing device. The state of the link is thereafter advertised by way of Border Gateway Protocol (BGP). Additionally, a method of discovering inter-chassis communication peers via BGP between the first and remote routing devices is provided. | 02-10-2011 |
20110194403 | Fault isolation in trill networks - In one embodiment, a method includes generating at an ingress routing bridge in a TRansparent Interconnection of Lots of Links (TRILL) network, a trace message for a specified flow along a path from the ingress routing bridge to a destination reachable through the TRILL network, transmitting a single trace message from the ingress routing bridge to a next-hop routing bridge in the TRILL network, receiving a plurality of reply messages in response to the transmitted trace message, and identifying the routing bridges in the path and a location of any fault in the path. An apparatus for fault isolation in a TRILL network is also disclosed. | 08-11-2011 |
20120014261 | Monitoring A Flow Set To Detect Faults - In certain embodiments, monitoring a flow set to detect faults includes identifying, by a first maintenance end point, a flow set comprising flows that utilize a paths from the first maintenance end point through one or more intermediate nodes to a second maintenance end point. Continuity check messages are generated. Each continuity check message is formatted as a data packet that an intermediate node forwards. Each continuity check message comprises a header comprising a maintenance indicator. The continuity check messages are transmitted on the flows to allow the second maintenance end point to monitor the paths. | 01-19-2012 |
20120106360 | DUAL-HOMING FOR ETHERNET LINE SERVICES - Techniques are described which provide mechanisms for dual-homing an access ring for virtual private wire service (VPWS) Ethernet line (E-Line) services. The mechanism may provide resiliency against access ring failures and offer a restoration time of 50 msec upon failure. A method to provide such resiliency may generally include determining, at a first ring port of an access node, a ring failure in an Ethernet ring. Upon determining the first ring port of the access node is not situated on a same side of the Ethernet ring as a node designated as a ring protection link (RPL) owner, a message is transmitted on a second ring port of the access node towards a provider edge (PE) node. The message is used to activate pseudowires (PWs) at the PE node for virtual local area networks (VLANs) of the access node. | 05-03-2012 |
20120177054 | Managing Active Edge Devices in VPLS Using BGP Signaling - In one embodiment, a method includes establishing in a Virtual Private Local Area Network (LAN) Service (VPLS) over Multi-Protocol Label Switching (MPLS) network a floating pseudowire between a first provider edge router and a redundancy group having a plurality of provider edge routers each configured to forward data toward a external device. Each provider edge router in the redundancy group is configured to maintain an active link to the external device. A provider edge router that is not a member of the redundancy group sends data directed to the external device through the floating pseudowire. Only one provider edge router in the redundancy group receives and forwards the particular data to the external device. | 07-12-2012 |
20120201124 | DESIGNATED FORWARDER ELECTION FOR VPLS WITH BGP-BASED MAC LEARNING - In one embodiment, a network device may participate in an election process to elect one of two or more Provider Edge devices of a Redundancy Group to be a Designated Forwarder for the Redundancy Group, where the Redundancy Group is in a Service Provider network, and where the Redundancy Group serves a Customer Edge device of a customer network. The network device may forward multi-destination traffic to the Customer Edge device according to whether the network device is elected to be the Designated Forwarder for the Redundancy Group. Multi-destination traffic may include multicast traffic, broadcast traffic, or destination unknown unicast traffic. | 08-09-2012 |
20120201247 | Metro Ethernet Network With Scaled Broadcast And Service Instance Domains - A method of operation for a provider edge device of a core network includes receiving a customer frame from an access network; the customer frame having a first Virtual Local Area Network (VLAN) tag of a first predetermined bit length. The first VLAN tag including a service instance identifier. The service instance identifier of the first VLAN tag is then mapped into a second VLAN tag of a second predetermined bit length greater than the first predetermined bit length. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 08-09-2012 |
20120213222 | Single-homing and Active-Active Multi-homing in a Virtual Private LAN Service - In one embodiment, single-homing and active-active multi-homing is provided in a Virtual Private LAN Service (VPLS). A customer edge node actively communicates frames of a same Virtual Private Network (VPN) instance with two or more VPLS nodes of a VPLS network. The VPLS nodes are configured to appropriately forward frames throughout the VPLS network: without looping of a frame sent by the same external node back to the same external node, without flooding multiple copies of a frame to the same external node, and while performing learning of addresses in forwarding tables of said VPLS nodes such that said forwarding tables of said VPLS nodes converge despite frames of the same LAN service being received by said at least two of said VPLS nodes from the same external node. | 08-23-2012 |
20120233492 | Transmitting network information using link or port aggregation protocols - In one embodiment, a method includes receiving at a network device, a packet from a component in a virtual network device, the packet transmitted across a link aggregation bundle connecting the virtual network device to the network device and indicating if the component is a master component in the virtual network device, and determining if an error exists in operation of the component as the master component or a slave component. An apparatus for assigning services to physical links in an aggregated link bundle is also disclosed. | 09-13-2012 |
20130121150 | Modifying Backbone Service Instance Identifiers based on an Identified Flow of Associated Frames - In one embodiment, backbone service instance identifiers (I-SIDs) of backbone frames are modified based on flow identification of frames encapsulated therein to induce entropy into the headers of the backbone frames. Backbone packet switching devices use the modified service instance identifier to load balance the corresponding frame through the backbone network. At an exit point of the backbone network, the original backbone service instance identifier (I-SID) associated with a frame encapsulated in a backbone frame is recovered from the modified service instance identifier, with this recovery typically including determining the flow identification of the frame encapsulated in the backbone frame. | 05-16-2013 |
20130148657 | MECHANISM FOR E-VPN INTEROPERABILITY WITH VPLS - In one embodiment, a network device in a set of network devices obtains a pseudowire label for a Provider Edge (PE) device, where the pseudowire label corresponds to a Virtual Local Area Network (VLAN) on the PE device. In addition, the network device obtains a set of one or more MAC addresses reachable via the PE device, wherein the set of network devices support Ethernet Virtual Private Network (E-VPN) and are in the same redundancy group such that the set of network devices are coupled to the same customer edge device. The network device stores the pseudowire label in association with the set of one or more MAC addresses. The network device uses the pseudowire label to encapsulate traffic associated with the VLAN that is received from the customer edge device and destined to the set of MAC addresses reachable via the PE device. | 06-13-2013 |
20130201986 | STITCHING MULTICAST TREES - Techniques for stitching multicast trees in a multiple data center environment. According to one embodiment, a technique for stitching multicast trees is provided, which includes determining, at an edge device of a data center, one or more Virtual Local Area Networks (VLANs) assigned to the edge device as a result of a designated forwarder election. An assigned forwarder message is sent by the edge device to one or more devices on the data center, the assigned forwarder message advertising the edge device as a designated forwarder for the VLANs assigned to the edge device. For each of the VLANs assigned to the edge device, the assigned forwarder message causes the edge device to be included in a multicast tree for the VLAN when the assigned forwarder message is received by specific ones of the devices in the data center that are associated with the VLAN. | 08-08-2013 |
20130235876 | MANAGING HIERARCHICAL ETHERNET SEGMENTS - In one embodiment, a method includes determining when a predetermined period of time has elapsed, and determining whether at least a first message has been obtained on a first port of a node during the predetermined period of time when it is determined that the predetermined period of time has elapsed. The method also includes identifying the first port as being connected to a single-homed site when it is determined that the at least first message has not been obtained on the first port during the predetermined period of time. The first port is identified as being connected to a multi-homed network, a multi-homed device, or a hierarchical Ethernet segment when it is determined that the at least first message has been obtained on the first port during the predetermined period of time. | 09-12-2013 |
20130254359 | ADDRESS RESOLUTION SUPPRESSION FOR DATA CENTER INTERCONNECT - An example method is provided that includes determining whether an address resolution protocol reply from a local machine has been received at an edge node; updating a local cache based on the reply from the local machine; and sending the reply to a plurality of edge nodes through a data plane of a data center interconnect. In more specific implementations, the method can include determining whether an address resolution protocol request has been received from the local machine. The method could also include updating a local machine cache based on the request. In certain implementations, the method can include determining whether the request is targeting the local machine; and dropping the request if the request is targeting the local machine. The method could also include sending the request through the data center interconnect if the request is not targeting the local machine. | 09-26-2013 |
20130308646 | ENABLING MEDIA ACCESS CONTROL ADDRESS MOBILITY IN AN ETHERNET VIRTUAL PRIVATE NETWORK - In one embodiment, a method includes obtaining an indication that a device is attached to a provider edge. The device has a media access control (MAC) address, wherein the device was previously attached to a first provider edge (PE) of a Multiprotocol Label Switching (MPLS) network. The method also includes issuing a first advertisement that identifies the MAC address. The first advertisement includes a first MAC address mobility attribute arranged to indicate a number of times the MAC address has moved with respect to the MPLS network. | 11-21-2013 |
20130315255 | SIGNALING OF ATTACHMENT CIRCUIT STATUS AND AUTOMATIC DISCOVERY OF INTER-CHASSIS COMMUNICATION PEERS - In an embodiment, a method of signaling status at a routing device is provided. In this method, the routing device establishes an inter-chassis control plane channel session with a remote routing device. Here, the routing device and the remote routing device are linked to a multi-homed routing device. The routing device then synchronizes with the remote routing device by way of the inter-chassis control plane channel session to identify a state of a link from the routing device to the multi-homed routing device. The state of the link is thereafter advertised by way of Border Gateway Protocol (BGP). Additionally, a method of discovering inter-chassis communication peers via BGP between the first and remote routing devices is provided. | 11-28-2013 |
20140010232 | Intra-Domain and Inter-Domain Bridging Over MPLS Using MAC Distribution Via Border Gateway Protocol - In one embodiment, a method includes receiving, by a first autonomous system border router (ASBR) of a first autonomous system (AS), a first plurality of provider-provisioned media access control (B-MAC) addresses via Interior Border Gateway Protocol (I-BGP). Each of first plurality of B-MAC addresses is associated with a provider edge (PE) device of the first AS. The first ASBR sends the first plurality of B-MAC addresses to a second ASBR of a second AS using Exterior Border Gateway Protocol (E-BGP). The first ASBR also receives via E-BGP a second plurality of B-MAC addresses each of which is associated with a PE device of the second AS. The first ASBR then distributes the second plurality of B-MAC addresses to each of the PE devices of the first AS using I-BGP. | 01-09-2014 |
20140064082 | CONGESTION MITIGATION AND AVOIDANCE - In one embodiment, a method is provided for congestion mitigation. In this method, a congestion level of data flows along a path is monitored relative to a threshold. Here, each data flow is associated with a flow identifier. Based on detection that the congestion level exceeds the threshold, the flow identifier of a number (e.g., one or more) of the data flows is changed to a different flow identifier. This change results in the number of the data flows redirected to a different path. In an alternate embodiment, another method is provided for congestion avoidance. In this method, a data flow transmitted along a single path is received, and the data flow is split into multiple micro data flows. A different flow identifier is then assigned to each micro data flow. This change results in the multiple micro data flows distributed along multiple different paths. | 03-06-2014 |
20140169376 | LOOP MITIGATION MECHANISM FOR ETHERNET NETWORKS - A technique is provided for mitigating loops in Ethernet networks. A first port in an Ethernet device receives an Ethernet frame. The frame includes a source identifier, a destination identifier, and a Virtual Local Area Network Identifier (VLAN ID). According to various embodiments, the VLAN ID (VID) has the encoding of both a community group as well as a source bridge ID. A VID database is accessed using the destination identifier and the VID to determine whether the first port has ingress enabled. A filtering database is accessed to determine an egress port for forwarding the Ethernet frame. | 06-19-2014 |
20140198795 | Metro Ethernet Network With Scaled Broadcast and Service Instance Domains - A method of operation for a provider edge device of a core network includes receiving a customer frame from an access network; the customer frame having a first Virtual Local Area Network (VLAN) tag of a first predetermined bit length. The first VLAN tag including a service instance identifier. The service instance identifier of the first VLAN tag is then mapped into a second VLAN tag of a second predetermined bit length greater than the first predetermined bit length. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 07-17-2014 |
20140233369 | ETHERNET VIRTUAL PRIVATE NETWORK SYSTEM FOR PROVIDING FAST PROTECTION FOR ACCESS RINGS - In one embodiment, a method includes obtaining a first indication from a first source included in an Ethernet ring and obtaining a second indication from a second source associated with a provider edge (PE) node The method also includes determining when the first indication and the second indication are indicative of a direct failure of the PE node and determining when the first indication and the second indication are indicative of a ring partition failure associated with the Ethernet ring. The direct failure of the PE node is identified when it is determined that the first indication and the second indication are indicative of the direct failure of the PE node, and the ring partition failure associated with the Ethernet ring is identified when it is determined that the first indication and the second indication are indicative of the ring partition failure associated with the Ethernet ring. | 08-21-2014 |
20150071080 | REDUNDANCY FOR INTER-AS L2VPN SERVICE WITH OPTIMAL FORWARDING - In one embodiment, a particular autonomous system border router (ASBR), in a control-plane media access control (MAC) learning (CPML) network, discovers other ASBRs in the CPML network, the particular ASBR and other ASBRs interconnected with respective ASBRs of a data-plane MAC learning (DPML) network. The particular ASBR calculates one or more internal shortest path first (SPF) trees rooted respectively at each of the other ASBRs in the CPML network, and upon receiving a MAC advertisement route for a given MAC address with a given next-hop IP address, it may determine a distance from the particular and each other ASBR in the CPML network to the given IP address based on the internal SPF trees. In response to the distance from the particular ASBR being shorter than the distance from each other ASBR, the particular ASBR is designated as a designated forwarder (DF) for traffic sourced from the given MAC address. | 03-12-2015 |