Abstract: An apparatus and related methods are provided to greatly reduce the negative impact of head of line (HOL) blocking. At a device (e.g., switch, router, etc.) configured to forward packets in a network, new packets that are to be forwarded from the device to other devices in the network are stored in a memory of the device. Entries are added to a queue link list for the at least one queue as new packets are added to the at least one queue. A detection is made when the at least one queue exceeds a threshold indicative of head of line blocking. For new packets that are to be added to the at least one queue, entries are added to a sub-queue link list for the plurality of sub-queues such that packets are assigned to different ones of a plurality of sub-queues when the at least one queue exceeds the threshold. Packets are output from the memory for the plurality of sub-queues according to the sub-queue link list.

Abstract: In one embodiment, a method includes receiving a multi-destination packet at a switch in communication with a plurality of servers through a network device, identifying a port receiving the multi-destination packet at the switch or a forwarding topology for the multi-destination packet, selecting a bit value based on the identified port or forwarding topology, inserting the bit value into a field in a virtual network tag in the multi-destination packet, and forwarding the multi-destination packet with the virtual network tag to the network device. The network device is configured to forward the multi-destination packet to one or more of the servers based on the bit value in the multi-destination packet. An apparatus for forwarding multi-destination packets is also disclosed.

Abstract: As switching device forwards frames through a fabric using high performance routing protocols without requiring changes in receiving and transmitting Ethernet end stations communicating through the fabric. Each frame received by an edge point of a high performance fabric is modified to support a high performance routing protocol while the frame is within the fabric and is restored to its original format when leaving the fabric. Within the fabric, virtual L2 addressing, assigned and maintained by the fabric, is applied to the frame to accommodate the high performance routing.

Abstract: Placing virtualization agents in the switches which comprise the SAN fabric. Higher level virtualization management functions are provided in an external management server. Conventional HBAs can be utilized in the hosts and storage units. In a first embodiment, a series of HBAs are provided in the switch unit. The HBAs connect to bridge chips and memory controllers to place the frame information in dedicated memory. Routine translation of known destinations is done by the HBA, based on a virtualization table provided by a virtualization CPU. If a frame is not in the table, it is provided to the dedicated RAM. Analysis and manipulation of the frame headers is then done by the CPU, with a new entry being made in the HBA table and the modified frames then redirected by the HBA into the fabric. This can be done in either a standalone switch environment or in combination with other switching components located in a director level switch.