Using HMAC for Error Correction over a Wireless Channel

Wireless communication systems have found their applications in almost every field of life. Most popular of these applications being web browsing, cellular telephony, SMS, MMS and audio & videoconferencing, just to name a few. There are however a few inherent problems in the communication over a wireless channel. The first one is that it is inherently prone to transmission errors and the second one is the security of data transmitted over the channel. Both the problems are researched separately by researchers, giving separate solutions. Forward error correction mechanisms are under research for error correction at the receiver side and cryptography has been proposed as a mechanism for data security. However these mechanisms have been dealt separately so far. We hereby propose a novel scheme that combines the two mechanisms together i.e. in our scheme we use symmetric cryptography in the form of H-MAC for data integrity protection as well as a means for the detection and correction of transmission errors at the receiver. Simulation results are given for our proposed scheme. This technique is an extension of soft input decryption. Results of simulations of joint channel coding and cryptography are compared to results of convolutional coding with the same coding rate. We also show that a coding gain is achieved in addition to solving both the outlined problems.