A method of estimating a parameter of a data channel model in a communication system, the method comprising: decoding a packet received through a noisy channel to convert the packet into data indicating one of a success and a failure of a reception of the packet, wherein packet reception is deemed successful if packet data is correctly received or correction of the packet data is possible, and packet reception is deemed to have failed if packet data is incorrectly received and correction of the packet data is not possible; selecting a channel model for simulating the noisy channel, the channel model having at least one unknown parameter; estimating the at least one unknown parameter using the data indicating the one of the success and the failure of the reception of the packet; and determining a size of a parity field of a forward error correction, FEC, symbol, using the estimated at least one unknown parameter, wherein the selected channel model corresponds to a Gilbert model including a random losses state in which individual packets are lost and a burst losses state in which serial packets are lost, wherein a probability of successfully receiving a packet when in a burst losses state is set to zero, wherein there is a first predetermined transition probability for transitioning from the random losses state to the burst losses state and a second predetermined transition probability for transitioning from the burst losses state to the random losses state, and wherein the data indicating the one of the success and the failure of the packet reception includes a data stream, and the method further includes partitioning data elements of the data stream into a determined unit of a sub group of data elements and performing the estimation of the at least one unknown parameter based on an average value of each sub group. decoding a packet received through a noisy channel to convert the packet into data indicating one of a success and a failure of a reception of the packet, wherein packet reception is deemed successful if packet data is correctly received or correction of the packet data is possible, and packet reception is deemed to have failed if packet data is incorrectly received and correction of the packet data is not possible; selecting a channel model for simulating the noisy channel, the channel model having at least one unknown parameter; estimating the at least one unknown parameter using the data indicating the one of the success and the failure of the reception of the packet; and determining a size of a parity field of a forward error correction, FEC, symbol, using the estimated at least one unknown parameter, wherein the selected channel model corresponds to a Gilbert model including a random losses state in which individual packets are lost and a burst losses state in which serial packets are lost, wherein a probability of successfully receiving a packet when in a burst losses state is set to zero, wherein there is a first predetermined transition probability for transitioning from the random losses state to the burst losses state and a second predetermined transition probability for transitioning from the burst losses state to the random losses state, and wherein the data indicating the one of the success and the failure of the packet reception includes a data stream, and the method further includes partitioning data elements of the data stream into a determined unit of a sub group of data elements and performing the estimation of the at least one unknown parameter based on an average value of each sub group. <EOS>