A media delivery system, comprising: one or more primary modules (12, 13); and at least one spare module (12a, 13a) that: monitors said one or more primary modules (12, 13); upon detection of failure of a primary module (12, 13) of the one or more primary modules (12, 13), performs a function of the failed primary module; wherein said one or more primary modules (12,13) periodically provide a status message each; and wherein said one or more primary modules (12, 13) multicast said status message; wherein the status message indicates a status of a corresponding primary module (12,13) by which the status message has been provided, one or more multicast groups from which said primary module is receiving one or more input streams, and one or more multicast groups to which said primary module is sending processed streams; wherein said at least one spare module determines the status of said one or more primary modules (12,13) from said status message; wherein said at least one spare module (12a, 13a) determines a failure of a primary module of the one or more primary modules (12, 13) if greater than a threshold number of status messages from the primary module of the one or more primary modules (12, 13) are not received; wherein said at least one spare module (12a, 13a) determines from said status message one or more multicast groups from which said failed primary module (12,13) is receiving one or more input streams; wherein upon detection of failure of said failed primary module (12,13), one of said at least one spare module (12a, 13a) joins said one or more multicast groups from which said failed primary module (12, 13) is receiving one or more input streams; wherein said at least one spare module (12a, 13a) determines from said status message one or more multicast groups to which a failed primary module is sending processed streams; and wherein upon detection of failure of said failed primary module, said one of said at least one spare module (12a, 13a) sends processed streams to said one or more multicast groups to which the failed primary module is sending processed streams. one or more primary modules (12, 13); and at least one spare module (12a, 13a) that: monitors said one or more primary modules (12, 13); upon detection of failure of a primary module (12, 13) of the one or more primary modules (12, 13), performs a function of the failed primary module; monitors said one or more primary modules (12, 13); upon detection of failure of a primary module (12, 13) of the one or more primary modules (12, 13), performs a function of the failed primary module; wherein said one or more primary modules (12,13) periodically provide a status message each; and wherein said one or more primary modules (12, 13) multicast said status message; wherein the status message indicates a status of a corresponding primary module (12,13) by which the status message has been provided, one or more multicast groups from which said primary module is receiving one or more input streams, and one or more multicast groups to which said primary module is sending processed streams; wherein said at least one spare module determines the status of said one or more primary modules (12,13) from said status message; wherein said at least one spare module (12a, 13a) determines a failure of a primary module of the one or more primary modules (12, 13) if greater than a threshold number of status messages from the primary module of the one or more primary modules (12, 13) are not received; wherein said at least one spare module (12a, 13a) determines from said status message one or more multicast groups from which said failed primary module (12,13) is receiving one or more input streams; wherein upon detection of failure of said failed primary module (12,13), one of said at least one spare module (12a, 13a) joins said one or more multicast groups from which said failed primary module (12, 13) is receiving one or more input streams; wherein said at least one spare module (12a, 13a) determines from said status message one or more multicast groups to which a failed primary module is sending processed streams; and wherein upon detection of failure of said failed primary module, said one of said at least one spare module (12a, 13a) sends processed streams to said one or more multicast groups to which the failed primary module is sending processed streams.