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.
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. 3. The method of claim 1 , further comprising: receiving a request for the first service; determining a number of control words sufficient to stream the first service for a predetermined period of time greater than one cryptographic period based on a program schedule associated with the first service; sending, from the computing device and to an ECM generator, a request for a particular number of control words equivalent to the number of control words determined to be sufficient to stream the first service for the predetermined period of time; and receiving, by the computing device and from the ECM generator, a second set of control words having a number of control words equivalent to the particular number of control words of the request.