Authentication and key agreement with perfect forward secrecy

A non-transitory processor-readable storage medium comprising instructions for preventing a bid-down attack on a system with a strong security protocol, the instructions comprising:

• code for receiving an attach request from a user equipment;
• code for sending an authentication request to a home network, wherein the authentication request includes an indication that a network supports the strong security protocol;
• code for receiving an integrity protected token from the home network, wherein the integrity protected token includes at least one bit configured to indicate that the network supports the strong security protocol;
• and
• code for sending the integrity protected token to the user equipment.

An apparatus for preventing a bid-down attack on a system with a strong security protocol, comprising:

• a memory;
• at least one processor operably coupled to the memory and configured to:
• receive an attach request from a user equipment;
• provide an authentication request to a home network, wherein
• the authentication request includes an indication that a network supports the strong security protocol;
• receive an integrity protected token from the home network, wherein the integrity protected token includes at least one bit configured to indicate that the network supports the strong security protocol;
• and
• provide the integrity protected token to the user equipment.

An apparatus for preventing a bid-down attack on a system with a strong security protocol, comprising:

• means for receiving an attach request from a user equipment;
• means for providing an authentication request to a home network, wherein the authentication request includes an indication that a network supports the strong security protocol;
• means for receiving an integrity protected token from the home network, wherein the integrity protected token includes at least one bit configured to indicate that the network supports the strong security protocol;
• and
• means for providing the integrity protected token to the user equipment.