An efficient software implementation of a forward error correcting code

Today, Forward Error Correcting (FEC) codes are mainly implemented in hardw are, and many believe that their complexity prohibits their software implem entation. This paper presents in detail how the performances of a software implementantion can be significantly improved. Different levels of optimiza tion which are independent of the working environment are presented and dis cussed. The coding throughput of 100 Mbps on an UltraSparc 1 shows that FEC codes can be easily added to multimedia applications without requiring ded icated hardware support. As a case study, we use FEC codes to protect AAL5- PDUs from cell losses in ATM networks.