System and method for encryption processing in a mobile communication system

An encryption processing method in a mobile communication system comprising an access terminal (AT), an access network (AN) for sending packet data to the AT on a radio channel, a packet control function (PCF) for controlling the AN, and a packet data service node (PDSN) for sending packet data to the AN through the PCF, comprising the steps of:

• encrypting a packet and sending the encrypted packet on a radio channel to the AN by the AT;
• requesting encryption information of the AT to the PCF by the AN, if it is indicated that the packet received from the AT was encrypted;
• determining whether the AT is authenticated and upon receipt of the request of the encryption information of the AT from the AN, extracting the encryption information of the AT if the AT is authenticated, and sending the extracted encryption information to the AN by the PCF;
• and
• decrypting the encrypted packet received from the AT based on the encryption information received from the PCF by the AN.

An encryption processing apparatus in an access terminal (AT) in a mobile communication system comprising the AT, an access network (AN) for sending packet data to the AT on a radio channel, a packet control function (PCF) for controlling the AN, and a packet data service node (PDSN) for sending packet data to the AN through the PCF, comprising:

• a message generator for generating a packet;
• an encrypter for encrypting the packet;
• and
• a transmitter for sending the encrypted packet to a receiver on a radio channel wherein the encrypter is configured to indicate whether the packet was encrypted.

An encryption processing method in an access terminal (AT) in a mobile communication system comprising the AT, an access network (AN) for sending packet data to the AT on a radio channel, a packet control function (PCF) for controlling the AN, and a packet data service node (PDSN) for sending packet data to the AN through the PCF, comprising the steps of:

• generating a packet upon user request;
• encrypting the packet;
• indicating whether the packet was encrypted;
• and
• sending the encrypted packet to a receiver on a radio channel.

An encryption processing apparatus in an access network (AN) in a mobile communication system comprising an access terminal (AT), the AN for sending packet data to the AT on a radio channel, a packet control function (PCF) for controlling the AN, and a packet data service node (PDSN) for sending packet data to the AN through the PCF, comprising:

• a radio frequency (RF) processor for receiving a packet from the AT on a radio channel;
• a controller for determining whether the packet was encrypted, and requesting encryption information of the AT to the PCF, if the packet was encrypted;
• and
• a decrypter for decrypting the encrypted packet received from the AT based on the encryption information of the AT received from the PCF.

An encryption processing method in an access network (AN) in a mobile communication system comprising an access terminal (AT), the AN for sending packet data to the AT on a radio channel, a packet control function (PCF) for controlling the AN, and a packet data service node (PDSN) for sending packet data to the AN through the PCF, comprising the steps of:

• receiving a packet from the AT on a radio channel;
• determining whether the packet was encrypted;
• requesting encryption information of the AT to the PCF, if the packet was encrypted;
• and
• decrypting the encrypted packet received from the AT based on the encryption information of the AT received from the PCF.