Describe the term G-DES and DESX

Question

Describe in brief the terms G-DES and DESX?

Answer 1

G-DES was invented by Schaumuller-Bichl to enhance the performance of DES by defining the cipher based on DES with a big block size, however without an increase in the quantity of computation needed. It was claimed that G-DES was as secure as DES as the cipher was based on DES. Though, Biham and Shamir showed that G-DES with the suggested parameter sizes is simply broken and that any modifications of G-DES parameters that outcome in a cipher faster than DES is less secure than the DES.