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USB Specification Expanding, Boosting Performance
Up to 40 Times Beyond Current Capability

Compaq, Hewlett-Packard, Intel, Lucent, Microsoft, NEC and Philips Are Leading Development

The PC industry leaders who brought Universal Serial Bus (USB) technology from concept to its current mainstream market acceptance have developed a next generation USB 2.0 specification that will extend performance by up to 40 times over existing capabilities. USB 2.0 (Hi-Speed USB) is fully compatible with USB 1.1 (Original USB), and uses the same cables and connectors. Compaq, Hewlett-Packard, Intel, Lucent, Microsoft, NEC and Philips are jointly leading this initiative, which will enable new classes of high performance PC peripherals.

Last year at the Intel Developer Forum Spring 1999, the formation of the USB 2.0 Promoter Group was announced. Since then, tremendous progress has been made in the development of the technology. The final USB 2.0 specification was released on April 27, 2000, with a speed of 480Mb/s (megabits per second). Product development is in full swing, with dozens of industry vendors currently targeting their products to be available in the fourth quarter of 2000. Also, several public Hi-Speed USB demonstrations have been shown at recent events, such as the Intel Developer Forum, WinHEC, and the USB 2.0 Developer Conference. With the increased availability of USB-enabled PCs and USB peripherals on the market today, the need for legacy dependent input/output (I/O) connectivity is decreasing significantly. Hi-Speed USB will be a significant step toward providing additional I/O bandwidth and broadening the range of peripherals that may be attached to the PC.

USB: Developed to Simplify PC Peripheral Connections

The Universal Serial Bus (USB) specification is a standardized peripheral connection developed by leading PC industry companies. USB makes plugging in new peripherals easy with plug and play, is nearly 100 times faster than the original serial port, and supports multiple device connectivity. Because of these benefits, USB is enjoying broad market acceptance today.

USB allows expandability of the PC's capabilities via an external port, eliminating the need for users or integrators to open the system chassis. Since USB supports multiple peripheral devices simultaneously, it allows users to run numerous devices such as printers, scanners, digital cameras and speakers from a single PC. USB also allows for automatic device detection and installation, making connectivity a true plug-and-play experience for end users. USB's quick proliferation as the replacement for the serial port and other PC ports for I/O devices such as digital joysticks, phones, scanners and digital cameras has accelerated the production and availability of such devices. Several hundred of these devices are in the marketplace today, with many more on their way. In addition, virtually every new PC today has one or more USB ports, quickly moving the installed base of USB-capable PCs to the range of hundreds of millions.

Hi-Speed USB: An "Evolution" Underway

Hi-Speed USB extends the speed of the connection from 12 Mbps on Original USB up to 480 Mbps on Hi-Speed USB, providing an attachment point for next-generation peripherals which complement higher performance PCs and user applications. Hi-Speed USB is both forward and backward compatible with Original USB, resulting in a seamless transition process for the end user. In fact, Hi-Speed USB uses the same cables and connectors as Original USB. Hi-Speed USB offers a compelling opportunity for peripherals vendors to migrate their USB peripherals to higher performance, while still being able to sell the same peripherals into the huge installed base of USB-capable PCs. Hi-Speed USB is also expected to lead to the development of higher performance peripherals that will bring new applications to the PC.

Original USB's data rate of 12 Mbps is sufficient for many PC peripherals such as telephones, keyboards, mice, digital joysticks, floppy drives, digital speakers, and low-end printers. These peripherals will continue to operate with no change in Hi-Speed USB systems. The higher bandwidth of Hi-Speed USB will permit PC peripherals with more functionality, including higher resolution video conferencing cameras, next generation scanners and printers, fast storage units, and faster broadband Internet connections. It will make today's user applications more productive, such as taking the time to download a "roll" of digital photos from a few minutes on Original USB down to a few seconds on Hi-Speed USB. In addition, the higher bandwidth will support the most demanding PC user applications, such as digital image creation and interactive gaming, where multiple high-speed peripherals will be running simultaneously. The higher data rate of Hi-Speed USB will also open up the possibilities of new and exciting peripherals.

As with Original USB, Hi-Speed USB is expected to eventually be in industry chipsets. Once these chipsets reach high volume, it is expected that Hi-Speed USB will be about the same cost as USB is today. Because of this, Hi-Speed USB is expected to supercede Original USB, which is already a ubiquitous connector on PC systems today. Also like Original USB, Hi-Speed USB will satisfy the peripheral-interface needs of desktops, mobile systems and other classes of host platforms. To satisfy the needs of power-sensitive applications such as notebook computers, Hi-Speed USB will provide the same power-management mechanisms as Original USB to allow aggressive management of I/O power consumption. This is expected to allow Hi-Speed USB to find use even in demanding low-power systems.

Hi-Speed USB and 1394

I/O connectivity is being further advanced with the IEEE 1394 standard. Hi-Speed USB and 1394 primarily differ in terms of application focus. The Hi-Speed USB Promoter group expects Hi-Speed USB to be the preferred connection for most PC peripherals, whereas IEEE 1394's primary target is audio/visual consumer electronic devices such as digital camcorders, digital VCRs, DVDs, and digital televisions. Both Hi-Speed USB and 1394 are expected to co-exist on many consumer systems in the future.

Hi-Speed USB and 1394 differ in application focus because of continuous evolution of the current environment. Today, there is a large and rapidly increasing installed base of USB-capable PCs, and hundreds of USB peripherals in the marketplace that connect to the PC. It is a natural evolution to increase the speed of USB and provide an easy migration path for existing USB peripherals. In the A/V consumer electronics equipment industry, IEEE 1394 is on its way to becoming the dominant connector. Therefore, if a PC wants to connect to one of these devices, it needs an IEEE 1394 connection.

They also support different connection models. Hi-Speed USB continues to use a low cost host-centric connection model, which is the best solution for a PC connection to PC peripherals. The added capability of a peer-to-peer connection enabled by IEEE 1394, however, allows a PC to connect to a cluster of consumer electronics devices, such as one that might exist in the family room.

Leading the Development of Hi-Speed USB

The companies that are leading the development of Hi-Speed USB have the expertise needed to focus on a specification that supports higher functionality peripherals. The Hi-Speed USB core team includes four members of the Original USB core team (Compaq, Intel, Microsoft, and NEC), and three new members (Hewlett Packard, Lucent and Philips). As with Original USB, members of this promoters group will not charge royalties for essential patents required to implement products compliant with the Hi-Speed USB specification.

For more information, see the USB Implementers Forum web site at