The secure mobile terminal installed an add-on secure message management toolkit which
developed with Java 2 Micro Edition (J2ME). It is includes user’s certificate, system parameters, and
some functions such as encryption/decryption, message segments/reassembles, messages management
and system setting etc. The secure message management toolkit does not change the traditional
message input/output interfaces in the mobile terminal, but is built on top of them, it is like a new
message management interface, where user receives and sends all messages. The user chooses an
option to read or send a secure message or plain text message. On the secure gateway side, a
corresponding application runs on the secure gateway, the application encrypts all messages before
sending to GSM modem, and decrypts all messages coming from GSM modem. The secure gateway
provides services to application servers by web services