Patent Document ID: 9473463
Application ID: 14445799

Base Claim:
1. A method comprising: caching concurrently, by a computing device, a first set of control words and a first set of entitlement control messages (ECMs) associated with the first set of control words; encrypting a transport stream, for a first service, using a first control word of the first set of control words during a first cryptographic period; encrypting the transport stream, for the first service, using a second control word of the first set of control words different from the first control word during a second cryptographic period, wherein the second cryptographic period occurs after the first cryptographic period; encrypting the transport stream, for the first service, using the first control word of the first set of control words during a third cryptographic period, wherein the third cryptographic period occurs after the first cryptographic period and the second cryptographic period; inserting into the transport stream, for the first service, a first ECM, of the first set of ECMs, corresponding to the first control word; and sending, to a device downstream from the computing device, the transport stream.

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Claim 6:
6. The method of claim 1 , further comprising: receiving, by the computing device, a second set of control words and a second set of ECMs associated with the second set of control words for use with a different transport stream associated with a second service different from the first service.