Realtek Semiconductor Inc.

Batuhan Okur

Turgut Sefket Aytur

Venkatesh Rajendran

Ping-Wen Ong

Saurabh Garg

Frederic Battaglia

Ran-Hong Yan

Fred Battaglia

Certified Wireless USB 1.0 (CWUSB) defines two different types of association: cable association and numeric association. In the numeric association, the CWUSB host and device use a specific protocol to exchange the security information. At final stage of this information exchange, both host and device need to display a number asking user's feedback. Once this is done, both host and device will be able to generate the connection key as the shared secret for the following secured communication. One problem of this numeric association method is that device needs to be able to display the numbers. For certain class of device that has capability to display an image, there is a natural way to add this function to them. A method for this class of devices is described. Another kind of association, which is not defined in the CWUSB 1.0, is manual association. User needs only to manually type in the Connection Key coming from the CWUSB device. There are many ways to delivery the key, but it is very easy for device that can display an image.

Association using USB video adapter

Universal Serial Bus (USB) is a Master/Salve or Host/Device system in which there is only one host and one or more devices connected by cables to the host. To connect a USB device to a different host controller (say another PC), the user unplugs the USB cable and establishes the connection physically by plugging the cable into the new host controller interface. Certified Wireless USB (CWUSB), a logical extension to the USB, preserves the USB connection model, except that the link between the host and the device is now using a wireless technology. A wireless device is usually connected to only one wireless host at a given point of time, even though several wireless hosts may be co-located in the same physical neighborhood. The connection between the wireless host and device is initiated by the device. A device usually selects a wireless host from a stored set of known hosts that have established a trusted relationship with the device. If more than one wireless host is operating in the same neighborhood, there is no well known established procedure for the device to select a particular wireless host to establish a connection.

CWUSB host management system

Certified Wireless USB 1.0 defines two different types of association: cable association and numeric association. In order to implementation these two association methods, the CWUSB device needs to have either upstream USB connector (for cable association) or display capability (for numeric association). These extra requirements make the CWUSB device bulkier (one more USB connector) and/or more expensive (extra display components). For cheap and simple CWUSB devices, we need a simpler association method that is easy and cheap to implement. In a pre-packaged total solution, which includes a host and one or more device(s), we can use pre-association to smooth the user experience. The host and device(s) are pre-associated. When an end user starts to use this solution, they do not need to worry about the association at all.

Pre-association for CWUSB

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Irvine, CA, United States of America

Batuhan Okur