Method and apparatus for authentication and authorization

A method at an authentication, authorization, and accounting, AAA, server, comprising:

• sending a third message for a secondary authentication or authorization of an established session of a terminal device to the session management function entity, wherein the established session was previously authenticated or authorized in a first network;
• receiving a fourth message from the session management function entity, wherein the fourth message indicates that the terminal device is not applicable for re-authentication in a current, second network because the terminal device has moved from the first network to the current network, wherein the move between the current network and the first network comprises a change of core network type or change of radio access technology, RAT, type;
• and
• deciding to maintain the session or initiate a session release procedure for releasing the session of the terminal device based on the fourth message.

A session management function entity, comprising:

• a processor;
• and
• a memory coupled to the processor, said memory containing instructions executable by said processor, whereby said session management function entity is operative to:
• receive a third message for a secondary authentication or authorization of an established session of a terminal device from an authentication, authorization, and accounting, AAA, server, wherein the established session was previously authenticated or authorized in a first network;
• and
• send a fourth message to the AAA server, wherein the fourth message indicates that the terminal device is not applicable for re-authentication in a current, second network because the terminal device has moved from the first network to the current network, wherein the move between the current network and the first network comprises a change of core network type or change of radio access technology, RAT, type.

An authentication, authorization, and accounting, AAA, server, comprising:

• a processor;
• and
• a memory coupled to the processor, said memory containing instructions executable by said processor, whereby said AAA server is operative to:
• send a third message for a secondary authentication or authorization of an established session of a terminal device to the session management function entity, wherein the established session was previously authenticated or authorized in a first network;
• receive a fourth message from the session management function entity, wherein the fourth message indicates that the terminal device is not applicable for re-authentication in a current, second network because the terminal device has moved from the first network to the current network, wherein the move between the current network and the first network comprises a change of core network type or change of radio access technology, RAT, type;
• and
• decide to maintain the session or initiate a session release procedure for releasing the session of the terminal device based on the fourth message.