International Business Machines Corporation

Donald Eugene Denning

Craig Anthony Klein

Robert George Emberty

Jonathan Wade Ain

Edward Joseph Pawlowski

David Dale McBride

Kenneth Glenn Day

Daniel J Byers

Tina L Hernandez

Michael Dana Bowers

A method and apparatus for locating an un-located asset in a computer center including a plurality of assets connected together by a network. The method comprises the steps of host asset of the computer center, obtaining an address for the un-located asset; and sending a command from the host asset to the un-located asset, through the computer center network, for the un-located asset to produce a signal for physically locating the un-located asset. Preferably, the method further comprises the steps of sending a request from the host asset to the un-located asset, through the computer center network, for the un-located asset to confirm that the un-located asset is in the computer center; and in response to receipt of said request, the un-located asset sending a signal to the host asset to confirm that the un-located asset is in the computer center. For example, an IP 'SQUAWK' command may be issued from any computer asset or system in the computer center or network to the IP address of the un-located computer asset system. Preferably, the code needed to implement the SQUAWK command is contained in a patch that is loaded on the computer systems during initial system code load.

Locator for computer equipment

A data processing system and method are disclosed for simulating a hardware fault occurring on an expansion card coupled to the system utilizing a bus. The hardware fault to simulate is specified. A determination is made of a signal to output utilizing the bus to simulate the hardware fault occurring on the expansion card. The signal is output during operation of the expansion card such that the hardware fault occurring on the expansion card is simulated.

Data processing method and system for simulation of hardware faults utilizing a PCI bus

A secure communication circuit for use with a data communication interconnect adapter and method of operation thereof. The secure communication circuit includes a first data buffer coupled to a data input terminal, an encoder/decoder coupled to the first data buffer, a second data buffer coupled to the encoder/decoder and a switching device coupled to a data output terminal. The switching device is couplable to either the first or second data buffers. A controller, coupled to the (switching device, selectively connects the switching device to the first or second data buffers. In a related embodiment, the secure communication circuit further includes a first serializer/deserializer (SERDES) coupled to the data input and a second SERDES coupled to the switching device.

Circuit and method for providing secure communication over data communication interconnects

An improved system and method for extending interface communications for a SCSI. The system and method provides SCSI extenders that are able to extend SCSI communications over relatively long distances between at least two SCSI interfaces while also being fast and efficient in operation and inexpensive in implementation. The present system and method reduces latency, buffering, error recovery code, and other such additional hardware and software. SCSI signals are received from one SCSI interface, and the SCSI signals from the one SCSI interface are parallel loaded into a parallel register. The SCSI signals from the one SCSI interface are serialized into serial data, and the serial data from the parallel register is transmitted over an optical communication system. The transmitted serial data is converted back to the SCSI signals that were originally from the one SCSI interface. The SCSI signals that were originally from the one SCSI interface are received by and shifted into a data management and driver system, and the data management and driver system is used to manage and drive the SCSI signals from the one SCSI interface to another SCSI interface. The same system and methodology is applied to extend communications in both directions between the at least two SCSI interfaces. The data management and driver system arbitrates, selects, and drives SCSI signals from one SCSI interface to another SCSI interface. The data management and driver system includes a receive serial shift register and a driver logic device.

Data management small computer system interface (SCSI) extender for extending SCSI communications between SCSI interfaces located relatively far apart

An analog SCSI switch comprising initiator device ports, target device ports and a controller utilizing at least one analog multiplexor circuit is connected between a SCSI interface and multiple SCSI devices. The controller monitors the SCSI bus and controls all interfaces and ports. By monitoring the SCSI bus, the controller is constantly informed of the arbitration, selection and re-selection acts of the initiator device or target devices. An analog multiplexor circuit selectively connects the initiator device and target device directly, allowing direct communication between the initiator device and a particular target device for duration of the connection. Logic for the controller, contained in the switch onboard memory, utilizes a secondary logical unit number of a target device to map a target device port. Utilizing the analog multiplexor circuit, the switch connects the initiator device port to a selected, mapped target device port. Error recovery is accomplished between the target device and initiator device, thus eliminating the need for buffers. Addressability of the SCSI interface is expanded to cover the number of target device ports multiplied by the number of target devices.

Method and system for switching SCSI devices utilizing an analog multiplexor

Disclosed are a subsystem and a method for diagnosing a fiber optic network, the fiber optic network comprising a fiber having an optic stream adhering to a defined protocol of the fiber optic network, and comprising a target for receiving and responding to the optic stream. The diagnosis comprises receiving the fiber optic stream and converting the fiber optic stream to an electrical input stream with a FOSA (fiber optic subassembly), and recognizing, from the electrical input stream, a selected event (e.g., frame or command) related to the optic stream defined protocol. Then, in response to the recognition of the selected event, recognizing a selected pattern of the electrical input stream, e.g., employing mask logic, and injecting, in response to the recognition of the selected pattern, a transmission error into the optic stream, and transmitting the optic stream with the injected transmission error to the target, employing a FOSA. A FIFO buffer is coupled to the first FOSA for buffering the electrical input stream, and the mask logic is coupled to the FIFO buffer for injecting the transmission error at a selected point in the optic stream.

Diagnostic injection of transmission errors in fiber optic networks

An initiator device, in a data processing system utilizing a Serial Storage Architecture subsystem, directs an I/O process via secondary path if a primary path is unavailable, even if the primary path is shorter. Also, an initiator device may send outbound data frames, on a secondary path, simultaneously with the SCSI command. Additional flexibility is attained by utilizing an adapter and target storage devices that all support Out of Order Transfers ('OOT'). If a target supports OOT, individual data frames that comprise an I/O process may be sent on multiple paths, allowing greater flexibility in routing. Also, an initiator device may send outbound data frames, on an alternate path, simultaneously with the SCSI command.

Method and system for increasing spatial reuse in a serial storage

Disclosed are a switching system and method for a Small Computer System Interface (SCSI). The SCSI has a plurality of ports coupled to devices having differing priorities including a highest priority (initiator) and lower priorities (targets). The present invention interconnects a plurality of the highest priority initiator devices to the lower priority target devices. A plurality of analog switches are each coupled to one of the initiator device ports and to the lower priority target device ports, preferably on a singular target bus, for selectively interconnecting the coupled initiator device to the lower priority target device ports. A controller is coupled to the initiator devices and to the plurality of analog switches, and is responsive to requests for connection from the initiator devices for arbitrating amongst the initiator devices to operate the analog switches to interconnect only one of the initiator device ports to the lower priority target device ports.

Switching multi-initiator SCSI devices to a singular target bus

A system is provided for monitoring signals transmitted over one or more optical serial interface channels in an ESCON environment. A formatter card mounts on bus connector in a general purpose tracing tool (GPT) and intercepts optical I/O signals being transmitted between a host processor and, a peripheral device. The signals are decoded into trace data words which are then partitioned into ESCON transaction frames and mapped into a block of GPT frames. The GPT block is stored on the formatter card and transmitted to the GPT when the GPT can accept the data. Data received by the GPT is interleaved with data from other formatter cards attached to other I/O channels (both ESCON and non-ESCON) and is displayed or printed in time-correlated format for analysis. Data can also be stored for later review.

Growing community of inventors

Tucson, AZ, United States of America

Donald Eugene Denning