Abstract: In one embodiment, a method includes obtaining an indication that a state associated with a node is to be changed and preventing data from being received on a first link. The method also includes updating at least one selected from a group including an incoming interface check (IIC) table and an outgoing interface (OIF) table to reflect the state. The state indicates that a second link is to be activated. Finally, the method includes allowing the data to be received on the second link after updating either or both the IIC table and the OIF table and after the timer duration for the NULL value for IIC has expired.

Abstract: In one embodiment, a method includes assigning at a switch in a layer 2 multipath network, costs to a link in the network, each of the link costs associated with a different graph for forwarding traffic in the network, transmitting the link costs to other switches in the layer 2 multipath network, and receiving and forwarding traffic according to one of the graphs. An apparatus is also disclosed.

Abstract: In one embodiment, a method includes receiving a packet at an input port of a network device, the input port having a plurality of queues with at least one queue for each output port at the network device, identifying a port group for transmitting the packet from the network device, the port group having a plurality of members each associated with one of the output ports, and selecting one of the queues based on utilization of the members. An apparatus for load balancing is also disclosed.

Abstract: Consistent with embodiments of the present disclosure, systems and methods are disclosed for providing per-group ECMP for multidestination traffic in a DCE/TRILL network. Embodiments enable per-group load balancing of multidestination traffic in DCE/L2MP networks by creating a new IS-IS PDU to convey the affinity of the parent node for a given multicast group. For broadcast and unknown unicast flooded traffic, the load balancing may be done on a per-vlan basis.

Abstract: In one embodiment, a method includes identifying a current topology associated with a virtual local area network (VLAN) and determining whether the current topology of the VLAN is to be moved to a base topology associated with a Transparent Interconnection of Lots of Links (TRILL) protocol. The method also includes moving the current topology of the VLAN to the base topology if it is determined that the current topology of the VLAN is to be moved to the base topology.

Abstract: In one embodiment, a method includes receiving a packet at an input port of a network device, the input port having a plurality of queues with at least one queue for each output port at the network device, identifying a port group for transmitting the packet from the network device, the port group having a plurality of members each associated with one of the output ports, and selecting one of the queues based on utilization of the members. An apparatus for load balancing is also disclosed.

Abstract: Methods and apparatus for providing in-order delivery in Fibre Channel (FC) fabric are disclosed. A topological change between a first switch and a second switch is evaluated to determine whether the topological change may result in out-of-order delivery. If it is determined that the topological change may result in out-of-order delivery, a flush frame is sent to the second switch and stop-on-mark is performed on all interfaces of affected links. Upon receiving the flush frame, the second switch drains all virtual output queues (VOQs) and sends an acknowledgement frame to the first switch. The first switch resumes in-order-delivery in an affected link after receiving the acknowledgement frame or expiration of a lifetime time of a frame.

Abstract: Techniques are described which facilitate multi-destination forwarding in a Layer 2 Multipath (L2MP) network which includes an emulated switch. The emulated switch may correspond to two or more underlying peer link switches in the L2MP network, in which each of the peer link switches is linked to a Classical Ethernet (CE) switch over a virtual port channel (vPC). Traffic received by one of the peer link switches over the vPC is automatically forwarded to the other peer link switch (or switches). Multi-destination frames originating from the L2MP network addressed to hosts within the CE network are sent over only one of the peer link switches.

Abstract: In one embodiment, a method includes assigning at a switch in a layer 2 multipath network, costs to a link in the network, each of the link costs associated with a different graph for forwarding traffic in the network, transmitting the link costs to other switches in the layer 2 multipath network, and receiving and forwarding traffic according to one of the graphs. An apparatus is also disclosed.

Abstract: In one embodiment, a method includes establishing a link between two N_Port Identifier Virtualization (NPIV) switches, the link having a high cost assigned thereto. The NPIV switches are in communication with a plurality of hosts through an N_Port Virtualization (NPV) device. The method further includes receiving at a first of the NPIV switches, an indication of a failure at a second of the NPIV switches, receiving data at the first NPIV switch, the data destined for one of the hosts associated with a domain of the second NPIV switch, and forwarding the data to the NPV device for delivery to the host, wherein a Fibre Channel Identifier (FCID) of the host is the same before and after the failure at the second NPIV switch. An apparatus is also disclosed.

Abstract: Certain embodiments of the present disclosure generally relate to allocating a sub-area of Fibre Channel addresses (FCIDs) to a device. A range of addresses may be assigned to the device using a mask address, where the most significant bits represent a mask and the least significant bits represent a sub-range of FCIDs available to be assigned to the device. Therefore, routing information may be stored efficiently in a Ternary Content Addressable Memory (TCAM) by storing a single entry in the TCAM for each sub-area of FCIDs allocated to a device, instead of storing an entry for each FCID. The single entry may indicate the mask address and the width of the mask.

Abstract: In one embodiment, a method includes obtaining an indication that a state associated with a node is to be changed and preventing data from being received on a first link. The method also includes updating at least one selected from a group including an incoming interface check (IIC) table and an outgoing interface (OIF) table to reflect the state. The state indicates that a second link is to be activated. Finally, the method includes allowing the data to be received on the second link after updating either or both the IIC table and the OIF table and after the timer duration for the NULL value for IIC has expired.

Abstract: Methods and apparatus for providing in-order delivery in Fibre Channel (FC) fabric are disclosed. A topological change between a first switch and a second switch is evaluated to determine whether the topological change may result in out-of-order delivery. If it is determined that the topological change may result in out-of-order delivery, a flush frame is sent to the second switch and stop-on-mark is performed on all interfaces of affected links. Upon receiving the flush frame, the second switch drains all virtual output queues (VOQs) and sends an acknowledgement frame to the first switch. The first switch resumes in-order-delivery in an affected link after receiving the acknowledgement frame or expiration of a lifetime time of a frame.