FEC technology transmits a fixed overhead of redundant information enabling the receiver to reconstruct a number missing IP packets. The FEC transmitter generates “Check sum” IP packets for a number of IP packets. Allowing the transmitter to transmit more overhead (FEC packets) allows for correction of more network errors. The FEC transmitter also “interleaves” IP packets in order to enable the correction of consecutive lost IP packets (burst errors). The packet interleaving and check sum generation process generates latency in the transmitter and receiver.
Details of FEC are as follows:
- FEC’s transmitting more overhead (FEC packets) can correct more network errors.
- FEC’s need IP packet interleaving to correct for consecutive lost IP packets.
- The more IP packets which are interleaved the longer burst packet losses can be recovered by the FEC, but the latency is proportional with the number of interleaved packets.
- The interleaving method (Matrix shape, number of Columns and rows) determinates the FEC’s error correcting capabilities for burst errors and single packet losses.
- The FEC latency and overhead for a given matrix size is constant at all times.