Which of the following statements are true about the implementation of the FEC/A-FEC technology?

The edge device at the transmit end receives and optimizes original packets. Meanwhile, itaccumulates original packets and constructs a packet group.

The edge device at the transmit end performs FEC encoding on the original packets in the group, and generates FEC redundant packets.

After receiving the original packets and redundant packets, the edge device at the receive end detects the packet loss information, re-constructs a packet group, and recovers the lost packets.

The edge device at the receive end performs FEC decoding on the received original packets and redundant packets in the same group to obtain the original packets.