A Scheme for Enhancing Transmission Rate on Asynchronous Secure Communication

Abstract

In asynchronous communication data of 00h~1Fh are used as all kinds of control characters, and 7Fh also is used as control character in some protocol such as Kermit. Therefore, data of this area must be converted to other form for transmission to prevent the misconception as control characters. This thesis presents several methods for character conversion that prevent the lengthening of data and enhance the overall efficiency of communication by transmitting with a certain conversion and without adding special characters on control-like characters occurring when data are transmitted with ciphering onto asynchronous communication path. For such conversion, the scope of transmitted data was supposed and efforts were made not to exceed that scope. Experiments showed that this method is better in communication speed than the existing ones and that ciphering has no problem by confirming the randomness of ciphered data.