Abstract: An apparatus and method are provided for connecting a host Enterprise System Connection Architecture (ESCON) Input/Output (I/O) interface to a cache of a data storage system. The apparatus includes (a) a set of at least 4 pipelines, each pipeline being coupled on a first end to the host ESCON I/O interface and being coupled on a second end to the cache, (b) a plurality of line processors, each line processor controlling one or more of the pipelines of the set of pipelines, and (c) in each pipeline, a protocol engine, the protocol engine configured to distinguish user data from frame header data and separate the user data from the frame header data for transport over the pipeline.

Abstract: An apparatus and method are provided for connecting a host Enterprise System Connection Architecture (ESCON) Input/Output (I/O) interface to a cache of a data storage system. The apparatus includes (a) a set of at least 4 pipelines, each pipeline being coupled on a first end to the host ESCON I/O interface and being coupled on a second end to the cache, (b) a plurality of line processors, each line processor controlling one or more of the pipelines of the set of pipelines, and (c) in each pipeline, a protocol engine, the protocol engine configured to distinguish user data from frame header data and separate the user data from the frame header data for transport over the pipeline.

Abstract: A shared resources service processor facilitates messaging between line processors and provides a single point of contact for a user interfacing with line processor(s), for example in a storage system interface. Shared memory is divided into “mailboxes” that are used to communicate between the line processors and the service processor. The service processor issues a system management interrupt to any or all of the line processors. This interrupt indicates to the line processor(s) that it should go out to the shared memory and read its respective mailbox. In operation, the service processor can deliver a message, i.e. command, to a line processor's mailbox, for example to tell a line processor to go off-line or on-line. The service processor will write the command into the mailbox and then assert the system management interrupt on the appropriate line processor that it wants to read the mailbox.

Abstract: A shared resources service processor facilitates messaging between line processors and provides a single point of contact for a user interfacing with line processor(s), for example in a storage system interface. Shared memory is divided into “mailboxes” that are used to communicate between the line processors and the service processor. The service processor issues a system management interrupt to any or all of the line processors. This interrupt indicates to the line processor(s) that it should go out to the shared memory and read its respective mailbox. In operation, the service processor can deliver a message, i.e. command, to a line processor's mailbox, for example to tell a line processor to go off-line or on-line. The service processor will write the command into the mailbox and then assert the system management interrupt on the appropriate line processor that it wants to read the mailbox.