The rapid development in mobile communication has transformed SMS as widespread tool for business and
social messaging. SMS services are growing day by day. With SMS, people can easily share personal and
official messages in a cost effective manner. SMS enables the transmission of up to 1120 bits alphanumeric
messages between mobile phones and external systems. It uses SMS center (SMS-C) for its routing operation in a
network and can be transmitted into another network through the SMS gateway . SMS usage is threatened
with security concerns , such as eavesdropping, interception and modification. SMS messages are transmitted
as plaintext between the mobile stations and the SMS center using the wireless network. SMS content are stored
in the systems of the network operators and can easily be read by their personnel. The A5 algorithm , which is
the GSM standard for encrypting transmitted data, can easily be compromised. Therefore, there is a need to
provide an additional encryption on the transmitted messages. As suggested by the name Short Message Service,
the data that can be held by an SMS message is very limited. One SMS message can contain at most 140 bytes
(1120 bits) of data, so one SMS message can contain up to