Patent ID: 9503785
Filing Date: 2016-11-22
CPC Classification: H04N

Claim Text:
1. A computer-implemented method for performing a control word sharing countermeasure, the method comprising: establishing a counter; receiving a first encrypted control message, wherein the first encrypted control message corresponds to a first channel; receiving a second encrypted control message; determining whether the second encrypted control message corresponds to the first channel; when the second message does not correspond to the first channel, incrementing the counter by a first value; when the second control message corresponds to the first channel, decrementing the counter by a second value, wherein the second value is different from the first value; receiving an encrypted management message, wherein the encrypted management message contains a key for decrypting one or more encrypted control messages; determining whether a value of the counter is below a threshold value; and when the value of the counter is below the threshold value: