Abstract: Methods and apparatus are provided for determining traffic characteristics and statistics for storage area network flows. An intelligent line card associated with a fibre channel switch is used to snoop selected flows in a storage area network. Flows are characterized using information that may include initiator target pairs and initiator target logical unit number (LUN) groupings. Selected flows are configured for monitoring and information about the selected flows is maintained. Selected flow information can be analyzed at a line card associated with a fibre channel switch.

Abstract: Methods and apparatus are provided for monitoring traffic characteristics using intelligent line cards. Selected flows are configured for monitoring based on characteristics such as an initiator target pairing or an initiator target and logical unit (LUN) grouping. Frames such as command frames associated with selected flows are forwarded to both an output port and a switch port analyzer (SPAN).

Abstract: Methods and apparatus are provided for improving network virtualization in a storage area network. A virtualization engine is divided into a front end virtualization engine and a back end virtualization engine cluster. The front end virtualization is associated with one or more virtual enclosure ports. The back end virtualization engine cluster performs resource intensive virtual address to physical address mapping. Virtualization engine resources can be dynamically added to a back end virtualization engine cluster while presenting a consistent interface to hosts connected to a storage area network.

Abstract: Disclosed are apparatus and methods for facilitating caching in a storage area network (SAN). In general, data transfer traffic between one or more hosts and one or more memory portions in one or more storage device(s) is redirected to one or more cache modules. One or more network devices (e.g., switches) of the SAN can be configured to redirect data transfer for a particular memory portion of one or more storage device(s) to a particular cache module. As needed, data transfer traffic for any number of memory portions and storage devices can be identified for or removed from being redirected to a particular cache module. Also, any number of cache modules can be utilized for receiving redirected traffic so that such redirected traffic is divided among such cache modules in any suitable proportion for enhanced flexibility.

Abstract: Disclosed are apparatus and methods for facilitating caching in a storage area network (SAN). In general, data transfer traffic between one or more hosts and one or more memory portions in one or more storage device(s) is redirected to one or more cache modules. One or more network devices (e.g., switches) of the SAN can be configured to redirect data transfer for a particular memory portion of one or more storage device(s) to a particular cache module. As needed, data transfer traffic for any number of memory portions and storage devices can be identified for or removed from being redirected to a particular cache module. Also, any number of cache modules can be utilized for receiving redirected traffic so that such redirected traffic is divided among such cache modules in any suitable proportion for enhanced flexibility.

Abstract: Disclosed are apparatus and methods for facilitating caching in a storage area network (SAN). In general, data transfer traffic between one or more hosts and one or more memory portions in one or more storage device(s) is redirected to one or more cache modules. One or more network devices (e.g., switches) of the SAN can be configured to redirect data transfer for a particular memory portion of one or more storage device(s) to a particular cache module. As needed, data transfer traffic for any number of memory portions and storage devices can be identified for or removed from being redirected to a particular cache module. Also, any number of cache modules can be utilized for receiving redirected traffic so that such redirected traffic is divided among such cache modules in any suitable proportion for enhanced flexibility.

Abstract: Methods and apparatus are provided for efficiently selecting virtualization engines in storage area networks. Initiators, targets, and candidate virtualization engines associated with a virtual logical unit number (VLUN) are identified and characteristics such as latency, network topology, load, and mirroring and striping characteristics are analyzed and used to efficiently select a virtualization engine for a particular VLUN in a storage area network. A virtualization engine can be implemented in a line card associated with a fibre channel switch.

Abstract: According to the present invention, methods and apparatus are provided for improving data transfers between hosts and targets connected through fibre channel switches. A host connected intelligent port and a target connected intelligent port associated with fibre channel edge switches are configured to snoop frames from the host and target and establish flows for acceleration. The host connected intelligent port and the target connect intelligent port preemptively respond to host and target transmissions to reduce data transfer latency.

Abstract: Methods and apparatus are provided for improving network virtualization in a storage area network. A virtualization engine is divided into a front end virtualization engine and a back end virtualization engine cluster. The front end virtualization is associated with one or more virtual enclosure ports. The back end virtualization engine cluster performs resource intensive virtual address to physical address mapping. Virtualization engine resources can be dynamically added to a back end virtualization engine cluster while presenting a consistent interface to hosts connected to a storage area network.

Abstract: Methods and apparatus are provided for determining traffic characteristics and statistics for storage area network flows. An intelligent line card associated with a fibre channel switch is used to snoop selected flows in a storage area network. Flows are characterized using information such as initiator target pairs and initiator target LUN groupings. Selected flows are configured for monitoring and information about the selected flows is maintained. Selected flow information can be analyzed at a line card associated with a fibre channel switch.

Abstract: Methods and apparatus are provided for monitoring traffic characteristics using intelligent line cards. Selected flows are configured for monitoring based on characteristics such as an initiator target pairing or an initiator target and logical unit (LUN) grouping. Frames such as command frames associated with selected flows are forwarded to both an output port and a switch port analyzer (SPAN).

Abstract: Methods and apparatus are provided for improving the configuration and allocation of storage resources in a fibre channel fabric. Network topology information and loop topology information is used to increase data availability and data access efficiency. For example, devices in different loops are selected for striping and devices connected to a host through different ports and switches are selected for mirroring. Link speed, quality of service, credits, and the availability of trunking links can also be considered.

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 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.