A method of correcting errors in a packet based communications system comprises generating m parity packets from each group of k consecutive data packets to form a code word of k data packets and m parity packets. Each parity packet is a combination of two or more data packets, and each data and parity packet includes a sequence number representative of a relative position of the packet in the code word. The method also includes examining, after transmission, the sequence number associated with each packet to determine if one or more packets from the code word is missing. If any packets are missing, the method includes identifying the one or more missing packets. The method further includes processing the data packets and the parity packets according to the combinations of data packets used to generate the parity packets, so as to recover one or more missing packets.