Source failover on a MediaConnect flow

Merge mode combines the sources into a single stream, allowing a graceful recovery from any single-source loss. If you set the failover mode to Merge, you can set the recovery window, which is the size of the buffer (delay) that you want MediaConnect to maintain. A larger recovery window means a longer delay in transmitting the stream, but more room for error correction. A smaller recovery window means a shorter delay, but less room for error correction. Sources used this way need to be binary identical, which means that they need to have originated from the same encoder. MediaConnect must also receive content from the two sources at the same time. Additionally, if the sources use RTP protocol, they must have RTP headers with aligned sequence numbers and they must also comply with the SMPTE ST 2022-7 standard.

Failover mode allows switching between a primary and a backup stream. This switching facilitates an easy transition to a more reliable stream. If you set the failover mode to Failover, you can specify a source as the primary source. The second source serves as the backup. If you don’t specify a primary source, MediaConnect treats both sources with equal priority, and switches to the available source as needed.

In the Merge mode, MediaConnect uses content from both sources. The flow randomly selects one of the sources to start with. If that source is missing a packet, the flow pulls the missing packet from the other source. For example, if the flow is using source A and packet 123 is missing, MediaConnect pulls in packet 123 from source B and continues using source A. In this mode, the two sources are binary identical/ST 2022-7 compliant.

In the Failover mode, if you don't specify a primary source, MediaConnect randomly uses one of the sources to provide content for the flow. If MediaConnect does not receive data from the source for 500 milliseconds, the flow switches to the other source, and can continue switching back and forth between sources as needed. If you do specify a primary source, MediaConnect uses that source to provide content for the flow. The flow switches to the other source if the primary source does not send data for 500 milliseconds, and switches back to the primary source as soon as data returns.