What one advantage of using EAP-TTLS instead of EAP-TLS as an authentication mechanism in 802.11WLAN?

A.
EAP-TTLS does not require the use of PKI.

B.
EAP-TTLS does not require an authenticator server.

C.
EAP-TTLS sends encrypted supplicant credentials to the authentication server.

D.
EAP-TTLS supports mutual authentication between supplicants and authentication servers.

E.
EAP-TTLS supports smartcard clients.

Explanation:
EAP-Tunneled Transport Layer Security (EAP-TTLS) is an EAP protocol that extendsTLS. It is widely supported across platforms; although there is no native OS support for this EAP protocol in Microsoft Windows, it requires the installation of small extra programs such as SecureW2. EAP- TTLS offers very good security. The client can but does not have to be authenticated via a CA- signed PKI certificate to the server. This greatly simplifies the setup procedure, as a certificate does not need to be installed on every client.
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