Abstract: In one embodiment, a solution is provided wherein redundant routers are treated as a single emulated switch. When a packet is received at a layer 2 edge switch from a host, the layer 2 edge switch may determine a switch identifier for the emulated switch using a destination anycast hardware address contained in the packet. The anycast hardware address may identify an emulated switch comprising a plurality of routers. Then a header may be added to the packet, the header including the switch identifier. Following that, the packet may be forwarded to another layer 2 switch along a shortest path from the layer 2 edge switch to the emulated switch.

Abstract: In one embodiment, a solution is provided wherein redundant routers are treated as a single emulated switch. When a packet is received at a layer 2 edge switch from a host, the layer 2 edge switch may determine a switch identifier for the emulated switch using a destination anycast hardware address contained in the packet. The anycast hardware address may identify an emulated switch comprising a plurality of routers. Then a header may be added to the packet, the header including the switch identifier. Following that, the packet may be forwarded to another layer 2 switch along a shortest path from the layer 2 edge switch to the emulated switch.

Abstract: In one embodiment, a solution is provided wherein redundant routers are treated as a single emulated switch. When a packet is received at a layer 2 edge switch from a host, the layer 2 edge switch may determine a switch identifier for the emulated switch using a destination anycast hardware address contained in the packet. The anycast hardware address may identify an emulated switch comprising a plurality of routers. Then a header may be added to the packet, the header including the switch identifier. Following that, the packet may be forwarded to another layer 2 switch along a shortest path from the layer 2 edge switch to the emulated switch.

Abstract: A Fiber Channel Switch which enables end devices in different Fabrics to communicate with one another while retaining their unique Fiber Channel Domain_IDs. The Switch is coupled to a first fabric having a first set of end devices and a second fabric having a second set of end devices. The Switch is configured to enable communication by the first set of end devices associated with the first fabric with the second set of end devices associated with the second set of end devices using the unique Domain_IDs of each of the first set and the second set of end devices. In one embodiment of the invention, the first and second fabrics are first and second Virtual Storage Array Networks (VSANs) respectively. In an alternative embodiment, the first fabric and the second fabric are separate physical fabrics.

Abstract: The present invention provides methods and devices for implementing a Low Latency Ethernet (“LLE”) solution, also referred to herein as a Data Center Ethernet (“DCE”) solution, which simplifies the connectivity of data centers and provides a high bandwidth, low latency network for carrying Ethernet and storage traffic. Some aspects of the invention involve transforming FC frames into a format suitable for transport on an Ethernet. Some preferred implementations of the invention implement multiple virtual lanes (“VLs”) in a single physical connection of a data center or similar network. Some VLs are “drop” VLs, with Ethernet-like behavior, and others are “no-drop” lanes with FC-like behavior. Some preferred implementations of the invention provide guaranteed bandwidth based on credits and VL. Active buffer management allows for both high reliability and low latency while using small frame buffers. Preferably, the rules for active buffer management are different for drop and no drop VLs.

Abstract: Increased usage of network links is provided and smaller forwarding tables are required. A combination of STP and Multipath methods may be implemented in a network. Frames may be forwarded between switches not only according to MAC addresses, but also according to switch IDs and local IDs. Switch IDs do not need to be globally unique, but should be unique within a particular network. Local IDs need only be unique within a particular switch. Some preferred implementations allow frames to be delivered in order to devices requiring in-order delivery. Preferably, core switches need only learn the switch IDs of each core switch and each edge switch, and the appropriate exit port(s) corresponding to each switch. Preferably, the forwarding tables of each edge switch indicate the addresses of each device attached to that edge switch, the address of each device that is in communication with an attached device and the address of every other switch in the network.

Abstract: A solution is provided wherein the interfaces between multiple chassis (e.g., edge switches) in a network of layer 2 devices and a spanning tree device are treated as a single emulated switch. This emulated switch effectively enables two different views to the two different sides. Thus, frames from the network of layer 2 switches destined to any port of the emulated switch may take any of the links (through any of the physical switches), thereby enabling effective load-balancing for frames traveling from the layer 2 network side into the spanning tree device. Meanwhile the spanning tree device does not recognize an illegal loop in its connection to two different edge switches as it views the two links as a single logical EtherChannel.

Abstract: In one embodiment, a solution is provided wherein redundant routers are treated as a single emulated switch. When a packet is received at a layer 2 edge switch from a host, the layer 2 edge switch may determine a switch identifier for the emulated switch using a destination anycast hardware address contained in the packet. The anycast hardware address may identify an emulated switch comprising a plurality of routers. Then a header may be added to the packet, the header including the switch identifier. Following that, the packet may be forwarded to another layer 2 switch along a shortest path from the layer 2 edge switch to the emulated switch.

Abstract: In one embodiment, a solution is provided wherein redundant routers are treated as a single emulated switch. When a packet is received at a layer 2 edge switch from a host, the layer 2 edge switch may determine a switch identifier for the emulated switch using a destination anycast hardware address contained in the packet. The anycast hardware address may identify an emulated switch comprising a plurality of routers. Then a header may be added to the packet, the header including the switch identifier. Following that, the packet may be forwarded to another layer 2 switch along a shortest path from the layer 2 edge switch to the emulated switch.

Abstract: A metric measurement mechanism is used to determine network characteristics such as latency and round trip time with more precision than that available from layer three metric measurement mechanisms. The metric measurement mechanism can use the same architecture used by layer three metric measurement mechanisms while more accurately measuring network latency and isolating network device processing delays.

Abstract: The present invention provides methods and devices for implementing a Low Latency Ethernet (“LLE”) solution, also referred to herein as a Data Center Ethernet (“DCE”) solution, which simplifies the connectivity of data centers and provides a high bandwidth, low latency network for carrying Ethernet and storage traffic. Some aspects of the invention involve transforming FC frames into a format suitable for transport on an Ethernet. Some preferred implementations of the invention implement multiple virtual lanes (“VLs”) in a single physical connection of a data center or similar network. Some VLs are “drop” VLs, with Ethernet-like behavior, and others are “no-drop” lanes with FC-like behavior. Some preferred implementations of the invention provide guaranteed bandwidth based on credits and VL. Active buffer management allows for both high reliability and low latency while using small frame buffers. Preferably, the rules for active buffer management are different for drop and no drop VLs.

Abstract: The present invention provides methods and devices for implementing a Low Latency Ethernet (“LLE”) solution, also referred to herein as a Data Center Ethernet (“DCE”) solution, which simplifies the connectivity of data centers and provides a high bandwidth, low latency network for carrying Ethernet and storage traffic. Some aspects of the invention involve transforming FC frames into a format suitable for transport on an Ethernet. Some preferred implementations of the invention implement multiple virtual lanes (“VLs”) in a single physical connection of a data center or similar network. Some VLs are “drop” VLs, with Ethernet-like behavior, and others are “no-drop” lanes with FC-like behavior. Some preferred implementations of the invention provide guaranteed bandwidth based on credits and VL. Active buffer management allows for both high reliability and low latency while using small frame buffers. Preferably, the rules for active buffer management are different for drop and no drop VLs.

Abstract: A method and apparatus to improve the performance of a SCSI write over a high latency network. The apparatus includes a first Switch close to the initiator in a first SAN and a second Switch close to the target in a second SAN. In various embodiments, the two Switches are border switches connecting their respective SANs to a relatively high latency network between the two SANs. In addition, the initiator can be either directly connected or indirectly connected to the first Switch in the first SAN. The target can also be either directly or indirectly connected to the second Switch in the second SAN. During operation, the method includes the first Switch sending Transfer Ready (Xfr_rdy) frame(s) based on buffer availability to the initiating Host in response to a SCSI Write command from the Host directed to the target. The first and second Switches then coordinate with one another by sending Transfer Ready commands to each other independent of the target's knowledge.

Abstract: A Fibre Channel Switch which enables end devices in different Fabrics to communicate with one another while retaining their unique Fibre Channel Domain_IDs. The Switch is coupled to a first fabric having a first set of end devices and a second fabric having a second set of end devices. The Switch is configured to enable communication by the first set of end devices associated with the first fabric with the second set of end devices associated with the second set of end devices using the unique Domain_IDs of each of the first set and the second set of end devices. In one embodiment of the invention, the first and second fabrics are first and second Virtual Storage Array Networks (VSANs) respectively. In an alternative embodiment, the first fabric and the second fabric are separate physical fabrics.

Abstract: A Fibre Channel Switch which enables end devices in different Fabrics to communicate with one another while retaining their unique Fibre Channel Domain_IDs. The Switch is coupled to a first fabric having a first set of end devices and a second fabric having a second set of end devices. The Switch is configured to enable communication by the first set of end devices associated with the first fabric with the second set of end devices associated with the second set of end devices using the unique Domain_IDs of each of the first set and the second set of end devices. In one embodiment of the invention, the first and second fabrics are first and second Virtual Storage Array Networks (VSANs) respectively. In an alternative embodiment, the first fabric and the second fabric are separate physical fabrics.

Abstract: Increased usage of network links is provided and smaller forwarding tables are required. A combination of STP and Multipath methods may be implemented in a network. Frames may be forwarded between switches not only according to MAC addresses, but also according to switch IDs and local IDs. Switch IDs do not need to be globally unique, but should be unique within a particular network. Local IDs need only be unique within a particular switch. Some preferred implementations allow frames to be delivered in order to devices requiring in-order delivery. Preferably, core switches need only learn the switch IDs of each core switch and each edge switch, and the appropriate exit port(s) corresponding to each switch. Preferably, the forwarding tables of each edge switch indicate the addresses of each device attached to that edge switch, the address of each device that is in communication with an attached device and the address of every other switch in the network.

Abstract: The present invention provides methods and devices for implementing a Low Latency Ethernet (“LLE”) solution, also referred to herein as a Data Center Ethernet (“DCE”) solution, which simplifies the connectivity of data centers and provides a high bandwidth, low latency network for carrying Ethernet and storage traffic. Some aspects of the invention involve transforming FC frames into a format suitable for transport on an Ethernet. Some preferred implementations of the invention implement multiple virtual lanes (“VLs”) in a single physical connection of a data center or similar network. Some VLs are “drop” VLs, with Ethernet-like behavior, and others are “no-drop” lanes with FC-like behavior. Some preferred implementations of the invention provide guaranteed bandwidth based on credits and VL. Active buffer management allows for both high reliability and low latency while using small frame buffers. Preferably, the rules for active buffer management are different for drop and no drop VLs.

Abstract: A network node determines the suitability of coupled devices for being remotely line powered before actually powering them. The node scan its ports to determine which ports are coupled to devices. The node then interrogates the coupled devices. A unique discovery tone or bit pattern is generated and sent to devices coupled to ports. The node then monitors the port for a return signal. If there is a return signal, it is compared to the transmitted discovery signal. The signal will be identical after allowing for line losses if the coupled device is suitable for remote line powering. If the comparison yields a match, the network node supplies remote line power to the device.

Abstract: Increased usage of network links is provided and smaller forwarding tables are required. A combination of STP and Multipath methods may be implemented in a network. Frames may be forwarded between switches not only according to MAC addresses, but also according to switch IDs and local IDs. Switch IDs do not need to be globally unique, but should be unique within a particular network. Local IDs need only be unique within a particular switch. Some preferred implementations allow frames to be delivered in order to devices requiring in-order delivery. Preferably, core switches need only learn the switch IDs of each core switch and each edge switch, and the appropriate exit port(s) corresponding to each switch. Preferably, the forwarding tables of each edge switch indicate the addresses of each device attached to that edge switch, the address of each device that is in communication with an attached device and the address of every other switch in the network.

Abstract: According to the present invention, methods and apparatus are provided to allow for distribution of fiber channel messages. Messages associated with a variety of applications can be distributed within a single logical fabric to physical connected but logically disconnected fabrics. Interconnecting switches forward messages to neighboring fabrics and aggregate responses before replying to a first fabric.