International Business Machines Corporation

Harry Cheselka

Edward Stanely Suffern

Norman Clark Strole

Mitchell Levy Loeb

William Gavin Holland

Charles Steven Lingafelt

Steven Wade Hunter

Chris Karabatsos

Jeffrey S Lucash

Lawrence G Mosher

Gerald J Hladik

Richard M Morrison

William F Nemecek

Dean A Stockwell

John Wagner Yarbrough

James Gregory Mulkey

William R Vincent

An improved solution for limiting the transmission rate of data over a network is provided according to an aspect of the invention. In particular, the transmission rate for a port is limited by rate limiting one of a plurality of queues (e.g., class/quality of service queues) for the port, and directing all data (e.g., packets) for transmission through the port to the single rate limited queue. In this manner, the transmission rate for the port can be effectively limited to accommodate, for example, a lower transmission rate for a port on a destination node.

Limiting transmission rate of data

A method and a computer program product for detecting link status in a blade system are provided. The method and computer program product provide for generating a first pattern of characters at a server blade of the blade system, transmitting the first pattern of characters from the server blade to an Ethernet switch of the blade system, and comparing a second pattern of characters to the first pattern of characters to determine whether a link from the Ethernet switch to a network is active in response to the server blade receiving the second pattern of characters from the Ethernet switch.

Detection of link status in blade systems

In a data processing system, a first system processor is coupled to a first system bus. The first system processor includes a first bus controller. A second system processor having a second bus controller is coupled to a second system bus. The first bus controller is then coupled to a management bus, and the second bus controller is coupled to the same management bus. Thereafter, at least one feature device is coupled to the first system bus, the second system bus, and the management bus. The feature device is also configured to communicate system processor communications with the first system processor via the first system bus. Next, a problem that affects system processor communications over the first system bus between the feature device and the first system processor is detected. In response to detecting such a communications problem, a command is sent to the feature device via the management bus. In response to receiving the command on the management bus, the feature device is configured to communicate system processor communications with the second system processor via the second system bus, wherein the feature device continues to operate in the data processing system as a result of communicating system processor communications with the second system processor via the second system bus in the presence of a problem that affects system processor communications over the first system bus. A second management bus may be coupled to the first bus controller, the second bus controller, and the feature device for providing a redundant management bus.

Method and system for managing system bus communications in a data

A remote fan out facility used in an information handling system including a plurality of data terminals located remotely from a central processor unit. Messages transmitted from the central processing unit to one of the plurality of data terminals are modified by creating and inserting a terminal device address into the outbound messages. The messages are then transmitted to a fan out box located near the addressed terminal. The fan out box strips the terminal address from the received message, decodes the stripped address, and directs the message to the appropriate data terminal according to the stripped decoded address. By this means, a single serial transmission link can be used to connect the central processing unit to a plurality of data terminals without undue modification of an existing system.

Remote fan out facility for data terminals

A multiple window display system is provided for displaying data from different applications in a multi-tasking environment. The display system includes plural screen buffers (12.sub.l to 12.sub.n) for storing character codes and attribute codes of data which may be displayed on the display screen. Task selection means (26) selectively couples the output of a single selected one of the plural screen buffers to the character generator (16) and attribute logic (18) at any given time. Address modification means (20.sub.l to 20.sub.n, 22.sub.l to 22.sub.n) permits changes to be made in the display windows. The software driver includes screen control blocks (32), window control blocks (34), presentation space control blocks (36), presentation spaces (38), and a screen matrix (40) in system memory. The presentation spaces (38) receive application data for plural windows of the displayable area. Each window defines the whole or a subset of a corresponding presentation space. The screen matrix (40) is mapped to the display screen and filters data from the windows of the presentation spaces to the screen buffer to designate which of the data will be shown in corresponding positions on the display screen.

Display of multiple data windows in a multi-tasking system

Disclosed is a display system having one or more display terminals, each of which includes a base unit which acts as a display and supports a keyboard for operation as a keyboard/display terminal, the terminal in turn interfacing with a plurality of features connected thereto. The features can be quite independent of the display, such as a card reader, or can be an operationally integral part thereof, such as extended capacity buffer operating jointly with the main buffer of the display, or can be interactive with the display, such as a selector pen or program function keyboard. The base unit and the features receive transmissions from a controller via a feature bus-out in the base unit and transmit to the controller via a feature bus-in in the base unit. The base unit also provides priority control in permitting features to respond to a controller poll. Commands are also directly addressable to the base unit and features by the controller, with the base unit performing interface functions between the controller and the features such as parity checking and time out error reporting.

Display terminal with modularly attachable features

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Raleigh, NC, United States of America

Harry Cheselka