
XML Security • 457
convention wherein Ifmmp Kpio actually means saying hello to your boyfriend John (that is, Hello John!).
Here each alphabet of the original message (that is, H, e, l, etc.) is changed to its next immediate alphabet
(that is, I, f, m, etc.). Thus, Hello becomes Ifmmp, and John becomes Kpio.
Thus, when John makes a phone call to you and your husband is around, you say Ifmmp Kpio! Only you
and John know its meaning! Cryptography uses the same basic principle. The sender and recipient of the
message decide on an encoding and decoding scheme and use it for communication.
In technical terms, the process of encoding messages is called ...