TRANSPORT PACKET DECRYPTION TESTING IN A CLIENT DEVICE

摘要

In a method for testing a transport packet decrypting module of a client
device, a first decryption operation of the transport packet decrypting module
is
implemented on a test encrypted control word using a content decryption key
ladder to derive a test control word, a second decryption operation of the
transport packet decrypting module is implemented on one or more test
transport
packets using the test control word via a predetermined content decryption
algorithm, the KIV is derived from the decrypted transport packets, and the
derived KIV is compared with a value stored in the client device to verify
whether
the transport packet decrypting module of the client device is functioning
properly.