Secure data transfer on a handheld communications device
View Patent ↗A handheld communications device for transmitting an encryption key is provided. The device comprises a display device, and a data processor. The data processor of the handheld communications device is in communication with the display device. The data processor is configured to generate an encryption key, and to vary a visual output of the display device over time in accordance with a bit sequence of the encryption key. The varying visual output comprises a sequence of colors and/or brightness levels output by the display device.
1. A handheld communications device comprising:
a display device having a backlight; and a data processor in communication with the display device, the data processor being configured to: generate an encryption key, the encryption key comprising a bit sequence; vary a predominant colour in an image over a period of time in an output generated on the display device to transmit a first part of the encryption key from the handheld communications device; and generate either a substantially solid white or gray image on the display and vary a sequence of brightness levels output by the backlight to transmit a second part of the encryption key.
2. The handheld communications device as claimed in claim 1 , wherein:
the display device is further configured to render a plurality of colours thereon; and the data processor is configured to vary a sequence of the plurality of colours and the sequence of brightness levels to transmit the first part of the encryption key.
3. The handheld communications device as claimed in claim 1 , wherein:
the display device is further configured to render a plurality of colours thereon; and the data processor is further configured to vary a sequence of the plurality of colours to transmit the first part of the encryption key.
4. The handheld communications device as claimed in claim 1 , further comprising;
a wireless interface; and
a memory, wherein the data processor is:
in communication with wireless interface and the memory; and
is further configured to
receive a temporary encryption key via the wireless interface;
compute a master encryption key from the temporary encryption key and the encryption key;
receive a second temporary encryption key via the wireless interface;
compute a public encryption key from the second temporary encryption key and the master encryption key; and
save the public encryption key in the memory.
5. The handheld communications device as claimed in claim 4 , wherein the data processor is further configured to:
encrypt data with the public encryption key;
transmit the encrypted data via the wireless interface;
receive via the wireless interface an authorization message in response to the encrypted data;
and provide a user with access to the communications device based on the authorization message.
6. The handheld communications device as claimed in claim 1 , wherein: a background colour is varied over the period of time in the output of the display device to transmit the first part of the encryption key.
7. A handheld communications device comprising a display device, a backlight for the display device and a data processor in communication with the display device, the handheld communications device comprising:
a data processor in communication with the display device, the data processor being configured to:
generate an encryption key via the data processor, the encryption key comprising a bit sequence; and
generate either a substantially solid white or gray image on the display device and vary a sequence of brightness levels of output by the backlight to transmit a first part of the encryption key.
8. The handheld communications device as claimed in claim 7 , wherein the data processor is further configured to: vary a background colour of an image over a period of time in an output generated on the display device to transmit a second part of the encryption key.
9. The handheld communications device as claimed in claim 7 , wherein the data processor is further configured to:
vary a sequence of plurality of colours in the output of the display device over the period of time to transmit a second part of the encryption key from the handheld communications device.
10. The handheld communications device as claimed in claim 7 , wherein the data processor is further configured to: vary a predominant colour in an image generated on the display device over the period of time to transmit a second part of the encryption key from the handheld communications device.
11. The handheld communications device as claimed in claim 7 , wherein the data processor is further configured to:
receive a temporary encryption key via a wireless interface in the handheld communications device;
compute a master encryption key from the temporary encryption key and the encryption key;
receive a second temporary encryption key via the wireless interface;
compute a public encryption key from the second temporary encryption key and the master encryption key via the data processor; and
save the public encryption key in a memory in the handheld communications device.
12. The handheld communications device as claimed in claim 7 , wherein the predominant colour is one of four colours used to encode the bit sequence for the second part of the encryption key.