A method and apparatus for improving performance in communication systems is provided. In one implementation, initial encoded data that has been encoded with a rateless code is received. A quality metric is determined for a communication medium on which the initial encoded data has been received. A modulation scheme used in sending the initial encoded data on the communication medium is identified. An estimate is determined, based on the identified modulation scheme and the determined quality metric, of an amount of mutual information being received per unit of received encoded data. An amount of mutual information being received is determined, based on the determined estimate.