Abstract: One embodiment of the present invention provides a switch. The switch includes a link aggregation module adapted to establish a virtual link aggregation group comprising a plurality of links coupling a network device to the switch and one or more other switches. The switch also includes an acknowledgment module adapted to identify an acknowledgment of a notification message from each of the one or more other switches, where the notification message includes port information associated with a local link participating in the virtual link aggregation group. The switch further includes a link selection module adapted to, in response to identifying the acknowledgment from each of the one or more other switches, determine a state for the local link based on the port information, where the state indicates whether the local link is an active link or a standby link for the virtual link aggregation group.

Abstract: One embodiment of the present invention provides a switch. The switch includes a link aggregation module and a link management module. The link aggregation module establishes a virtual link aggregation group comprising a plurality of links coupled to the switch and one or more other switches. The plurality of links includes a first and a second sets of links coupling a first and a second end devices, respectively. The link management module determines a current mode which indicates which of the sets of links is currently active, and operates the first and the second sets of links as active and standby links, respectively, for the virtual link aggregation group based on the current mode and a port role for a port participating in the virtual link aggregation group. The port role indicates whether the port is coupled to an active link or a backup link.

Abstract: One embodiment of the present invention provides a switch. The switch includes a packet processor and a spanning tree management module. The packet processor obtains information associated with a spanning tree from a message. The spanning tree management module, in response to the obtained information being superior to locally available information of the spanning tree, determines the port role of a local port of the switch for the spanning tree to be the root port and the port state of the local port for the spanning tree to be blocking.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a storage device, a hardware management apparatus, and a layer-2 management apparatus. The storage device stores a forwarding table, which includes an entry comprising a MAC address and an egress port for the MAC address. The hardware management apparatus determines whether a destination MAC address of a frame is present in a hardware table in memory of the switch. The layer-2 management apparatus, in response to a determination that the destination MAC address is not present in the hardware table, looks up a first entry comprising the destination MAC address in the forwarding table, and creates a second entry comprising the destination MAC address in the hardware table based on the first entry.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a network extension module, which maintains a mapping between a first virtual local area network (VLAN) identifier and a first global VLAN identifier of a network extension group. The network extension group is represented by a range of global VLAN identifiers for a tenant. A global VLAN identifier is persistent in a respective switch of the network and represents a virtual forwarding domain in the network. During operation, the network extension module includes the global VLAN identifier in a packet belonging to the first VLAN.

Abstract: One embodiment of the present invention provides a switch which comprises one or more ports adapted to receive packets. The switch is a member of a network of interconnected switches, and also comprises a path monitoring apparatus adapted to: in response to a control packet associated with a session within a predetermined time interval, set a receive indicator for the switch to an active state; and in response to absence of the control packet associated with the session within the predetermined time interval, set the receive indicator for the switch to an inactive state. The path monitoring apparatus is also adapted to set a path state associated with the session based on the receive indicators for the switch and other member switches. The switch also comprises a broadcast apparatus adapted to broadcast at least the receive indicator for the switch to the other member switches.

Abstract: A switch can reduce power consumption in a switch network by disabling under-utilized links between switches. The switch can include one or more line cards each operable to transmit and receive packets over a respective link to a remote switch. The switch can also comprise a control mechanism operable to place under-utilized links in standby mode whenever possible to conserve power. During operation, the switch can receive a standby request for placing a first link to a neighboring switch in a standby mode, and determines whether one or more eligible links to the neighboring switch can accommodate traffic from the first link. If the eligible links are able to accommodate traffic from the first link, and if the local switch and the neighboring switch agree to place the first link in standby mode, the local switch proceeds to place the first link in standby mode.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a storage device, a hardware management apparatus, and a layer-2 management apparatus. The storage device stores a forwarding table, which includes an entry comprising a MAC address and an egress port for the MAC address. The hardware management apparatus determines whether a destination MAC address of a frame is present in a hardware table in memory of the switch. The layer-2 management apparatus, in response to a determination that the destination MAC address is not present in the hardware table, looks up a first entry comprising the destination MAC address in the forwarding table, and creates a second entry comprising the destination MAC address in the hardware table based on the first entry.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a network extension module, which maintains a mapping between a first virtual local area network (VLAN) identifier and a first global VLAN identifier of a network extension group. The network extension group is represented by a range of global VLAN identifiers for a tenant. A global VLAN identifier is persistent in a respective switch of the network and represents a virtual forwarding domain in the network. During operation, the network extension module includes the global VLAN identifier in a packet belonging to the first VLAN.

Abstract: One embodiment of the present invention provides a switch. The switch includes a fabric switch module and a border module. The fabric switch module maintains a membership in a first fabric switch. The fabric switch includes a plurality of switches and operates as a single logical switch. The border module determines that the egress switch identifier in a first encapsulation header of a first packet is associated with a switch outside of the fabric switch. The first packet is forwardable in the first fabric switch based on the first encapsulation header. In response to the determination, the border module changes the ingress switch identifier in the first encapsulation header of the first packet to a first virtual switch identifier associated with a first virtual switch. This first virtual switch externally represents the first fabric switch.

Abstract: One embodiment of the present invention provides a switch. The switch comprises one or more ports, a link management module and a load balancing module. The link management module operates a port of the one or more ports of the switch in conjunction with a remote switch to form a virtual link aggregation. The load balancing module generates an index of a weight distribution vector based on address information of a multicast group associated with the virtual link aggregation. A slot of the weight distribution vector corresponds to a respective switch participating in the virtual link aggregation. In response to the index indicating a slot corresponding to the switch, the load balancing module designates the switch as primary switch for the multicast group, which is responsible for forwarding multicast data of the multicast group via the virtual link aggregation.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a storage device, a hardware management apparatus, and a layer-2 management apparatus. The storage device stores a forwarding table, which includes an entry comprising a MAC address and an egress port for the MAC address. The hardware management apparatus determines whether a destination MAC address of a frame is present in a hardware table in memory of the switch. The layer-2 management apparatus, in response to a determination that the destination MAC address is not present in the hardware table, looks up a first entry comprising the destination MAC address in the forwarding table, and creates a second entry comprising the destination MAC address in the hardware table based on the first entry.

Abstract: One embodiment of the present invention provides a switch. The switch includes a storage device, a mapping module, and a packet processor. During operation, the mapping module maintains a first and a second mappings. The first mapping, which can be in the storage device, is between a first service tunnel identifier and a first virtual local area network (VLAN) identifier. The second mapping is between the first VLAN identifier and an indicator, which indicates whether the switch is elected as a designated forwarder of multi-destination traffic for the first service tunnel identifier. If the indicator indicates that the switch is the designated forwarder of multi-destination traffic for the first service tunnel identifier, the packet processor determines an egress port, which corresponds to the first service tunnel, for a packet belonging to multi-destination traffic of the first VLAN.

Abstract: One embodiment of the present invention provides a switch in a network of interconnected switches. The switch includes a network extension module, which maintains a mapping between a first virtual local area network (VLAN) identifier and a first global VLAN identifier of a network extension group. The network extension group is represented by a range of global VLAN identifiers for a tenant. A global VLAN identifier is persistent in a respective switch of the network and represents a virtual forwarding domain in the network. During operation, the network extension module includes the global VLAN identifier in a packet belonging to the first VLAN.

Abstract: One embodiment of the present invention provides a computing system. The computing system includes a packet processor, a buffer management module, a data monitoring module, and a flow control module. The packet processor identifies a class of service indicating priority-based flow control associated with a remote computing system from a notification message. The buffer management module creates a buffer dedicated for frames belonging to the class of service from the remote computing system in response to identifying the class of service. The data monitoring module detects a potential overflow of the buffer. The flow control module operates in conjunction with the packet processor to generate a pause frame in response to detecting a potential overflow.

Abstract: One embodiment of the present invention provides a switch. The switch includes a packet processor and a spanning tree management module. The packet processor obtains information associated with a spanning tree from a message. The spanning tree management module, in response to the obtained information being superior to locally available information of the spanning tree, determines the port role of a local port of the switch for the spanning tree to be the root port and the port state of the local port for the spanning tree to be blocking.

Abstract: One embodiment of the present invention provides a switch. The switch comprises one or more ports, a link management module and a load balancing module. The link management module operates a port of the one or more ports of the switch in conjunction with a remote switch to form a virtual link aggregation. The load balancing module generates an index of a weight distribution vector based on address information of a multicast group associated with the virtual link aggregation. A slot of the weight distribution vector corresponds to a respective switch participating in the virtual link aggregation. In response to the index indicating a slot corresponding to the switch, the load balancing module designates the switch as primary switch for the multicast group, which is responsible for forwarding multicast data of the multicast group via the virtual link aggregation.

Abstract: Systems and techniques for performing network layer multicasting in a TRILL network are described. Some embodiments provide a system that receives multicast packet that includes a network-layer multicast-address. The multicast packet can be received on a first multicast tree associated with a first virtual network. Next, the system can determine, based on the network-layer multicast-address, a second multicast tree associated with a second virtual network over which the multicast packet is to be forwarded. The system can then forward the multicast packet on the first multicast tree associated with the first virtual network, and forward a copy of the multicast packet on the second multicast tree associated with the second virtual network.

Abstract: Systems and techniques for supporting multiple multicast trees are described. Some embodiments provide a system that determines an internal multicast group identifier based on a source address, a multicast address, and a multicast tree identifier field associated with a multicast packet. The system can then forward the multicast packet based on the internal multicast group identifier. Specifically, the system can determine a first set of bits based on the source address and the multicast address of the multicast packet. The system can determine a second set of bits based on the multicast tree identifier field of the multicast packet. Next, the system can combine the first set of bits and the second set of bits to obtain the internal multicast group identifier. In some embodiments, the scope of an internal virtual network identifier does not extend beyond a switch or a forwarding module within a switch.

Abstract: One embodiment of the present invention provides a switch. The switch includes a packet processor and a spanning tree management module. The packet processor obtains information associated with a spanning tree from a message. The spanning tree management module, in response to the obtained information being superior to locally available information of the spanning tree, determines the port role of a local port of the switch for the spanning tree to be the root port and the port state of the local port for the spanning tree to be blocking.