Method for identifying authentication function in extensible authentication protocol

The present invention relates to a method for identifying an authentication function in the scalable authentication protocol. The present invention relates to an EAP authentication function (e.g., EAP) used by a user terminal by comparing an identity pattern of a received EAP identity response message or by using a decoration of an identity. It can identify the authentication function of the user terminal without adding EAP message to find out AKA, EAP-TLS and EAP-TTLS, etc., and it is the default authentication function (for example, in case of error of received identity). By defining EAP-AKA) and transmitting an EAP message, an authentication function identification method in the scalable authentication protocol that can prevent unnecessary retransmission of an EAP identity request message is provided. To this end, the present invention provides an authentication function identification method, comprising: an identity reception step of receiving an identity response message of a scalable authentication protocol from a user terminal; Verifying an identity pattern from an identity response message of the received scalable authentication protocol; A function identification step of identifying an authentication function of an extensible authentication protocol with the user terminal according to the pattern of the identified identity; And performing an authentication process with the user terminal by transmitting a request and response message of an extensible authentication protocol according to the identified authentication function. Extensible Authentication Protocol, Identity Response Message, Identity Pattern, Decoration of Identity, EAP Authentication Function, EAP-AKA, EAP-TLS, EAP-TTLS