eap_peer_config::anonymous_identity field

anonymous_identity - Anonymous EAP Identity This field is used for unencrypted use with EAP types that support different tunnelled identity, e.g., EAP-TTLS, in order to reveal the real identity (identity field) only to the authentication server. If not set, the identity field will be used for both unencrypted and protected fields. This field can also be used with EAP-SIM/AKA/AKA' to store the pseudonym identity.