Symmetric key-based authentication in multiple domains

An authentication entity employing a multiple domain symmetric key-based authentication, the authentication entity comprising:

• a certificate issue request unit requesting a home domain authentication server to issue a certificate;
• a certificate/symmetric key receiver receiving the certificate issued by the home domain authentication server and a symmetric key in response to the certificate issue request;
• a certificate transmitter transmitting the certificate to the home domain authentication server or an external domain authentication server;
• and
• a certificate result receiver receiving a result of the certificate verification received from the home domain authentication server or external domain authentication server.

A home domain authentication server employing a multiple domain symmetric key-based authentication, the home domain authentication server comprising:

• a certificate issue request receiver receiving a certificate issue request from an authentication entity;
• a symmetric key/certificate generator generating a symmetric key and a certificate in response to the certificate issue request;
• and
• a symmetric key/certificate issuing unit issuing the symmetric key and the certificate to the authentication entity.

An external domain authentication server employing a multiple domain symmetric key-based authentication,

• wherein the external domain authentication server requests a home domain authentication server to verify the certificate received from an authentication entity and authenticates the authentication entity using the certificate verification result received from the home domain authentication server, and
• wherein the external domain authentication server comprises:
• a certificate receiver receiving the certificate submitted by the authentication entity;
• a domain server authentication unit authenticating the home domain authentication server using a public key authentication to establish communication channel with the home domain authentication server which has issued the certificate for verifying the certificate received from the authentication entity
• a domain communication unit which communicates with the home domain authentication server by establishing a secured communication channel therewith;
• a certificate verification request unit requesting the home domain authentication server to verify the certificate;
• a certificate verification result receiver receiving the certificate verification result from the home domain authentication server;
• and
• a certificate verification result transmitter transmitting information on whether the certification is successfully verified to the authentication entity by determining whether the certificate is verified on the basis of the result provided by the home domain authentication server.