Method for guaranteeing a device minimum bandwidth on a USB bus

Abstract

A method of guaranteeing a minimum sustained data transfer rate to a chosen device connected to a USB bus. A set of filter drivers are inserted in the driver stacks for at least two USB devices. These filter drivers are controlled by a filter driver controller that provides and receives information from the filter drivers. When a particular device needs a minimum sustained bandwidth for a transaction, the filter driver for that device notifies the filter driver controller. The filter driver controller then instructs the filter drivers for at least one other device to start interfering with USB transactions. This interference prevents the interfered with devices from using any of the USB bus bandwidth thereby providing a minimum sustained bandwidth to the non-interfered with device.

Description

FIELD OF THE INVENTION [0001] This invention relates generally to the Universal Serial Bus (USB) and more particularly to ensuring that a minimum amount of bandwidth is allocated to a particular device. BACKGROUND OF THE INVENTION [0002] The Universal Serial Bus (USB) is a peripheral bus specification developed by personal computer (PC) and telecommunication industry companies that brings the plug and play features of computer peripherals outside the PC box. This eliminates the need to install cards into dedicated computer slots and reconfigure the system. Personal computers equipped with USB allow computer peripherals to be automatically configured as soon as they are physically attached. This eliminates the need to reboot or run setup software. USB also allows multiple devices to run simultaneously on a computer, with dedicated hubs and peripherals such as monitors and keyboards also acting as additional plug-in sites. [0003] The Universal Serial Bus is defined in the Universal Se...

AI Technical Summary

Benefits of technology

[0007] In a preferred embodiment, the invention provides a minimum sustained data transfer rate to a chosen device connected to a USB bus. A set of filter drivers are inserted in the driver stacks for at least two USB devices. These filter drivers are controlled by a filter driver controller that provides and receives information from the filter drivers. When a particular device needs a minimum sustained bandwidth for a transaction, the filter driver for that device notifies the filter driver controller. The filter driver controller then instructs the filter drivers for at least one other device to start interfering with USB transactions. This interference may be to temporarily delay one or more transactions to one or more of the other devices until more bandwidth is available. This interference may also take the form of intercepting transactions from one or more of the other devices and returning an error condition. This interference may also be implemented by signaling the host computer that one or more of the other devices is disconnected from the USB bus. Then when the non-interfered with device no longer needs the minimum sustained data rate, the host computer is signaled that the device has been reconnected. This interference prevents the interfered with devices from using any of the USB bus bandwidth thereby providing a minimum sustained bandwidth to the non-interfered with device. Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

Problems solved by technology

This interference may be to temporarily delay one or more transactions to one or more of the other devices until more bandwidth is available.

This interference may also take the form of intercepting transactions from one or more of the other devices and returning an error condition.

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