Patent ID: 8695068

Claim:
A method for identifying a remotely located device, the method comprising: receiving device identification data from the device, wherein the device identification data includes: a device identifier, wherein the device identifier is a unique identifier of one of a number of known devices; and pixel irregularity data, wherein the pixel irregularity represents one or more pixel irregularities of at least one monitor of the device and wherein the pixel irregularity data is derived by the remotely located device by, for each of one or more pixels of a display of the remotely located device: (i) writing test data to the pixel, (ii) reading display data from the pixel, wherein the display data specifies a color currently displayed for the pixel, and (iii) comparing the test data to the display data to identify an irregularity of the pixel; determining that the device identifier identifies the device; comparing the pixel irregularity data to corresponding reference pixel irregularity data previously stored for the device; determining that the pixel irregularity data is consistent with the corresponding reference pixel irregularity data if the pixel irregularity data (i) does not indicate less pixel irregularity than the reference pixel irregularity data, (ii) does not indicate the absence of any pixel irregularity previously observed in the reference pixel irregularity data, and (iii) does not indicate greater pixel irregularity than the reference pixel irregularity data by more than a predetermined rate of deterioration; and authenticating the device as a recognized device upon determining that the pixel irregularity data is consistent with the corresponding reference pixel irregularity data.