ZyXEL Communications G-3000H Manual do Utilizador descarregar pdf (Página 83)

IEEE 802.1x Access Control

receives normal traffic without 802.1x-based authentication of the client. This is the default port control setting. While AP is setup as Force Authorized, Wireless

client (supported 802.1x client or none-802.1x client) can always access the network.

2. Force Unauthorized : Causes the port to remain in the unauthorized state, ignoring all attempts by the client to authenticate. The authenticator cannot provide

authentication services to the supplicants through the port. While AP is setup as Force Unauthorized, Wireless clients (supported 802.1x client or none-802.1x

client) never have the access for the network.

3. Auto : Enables 802.1x and causes the port to begin in the unauthorized state, allowing only EAPOL frames to be sent and received through the port. The

authentication process begins when the link state of the port transitions from down to up, or when an EAPOL-start frame is received requests the identity of the

client and begins relaying authentication messages between supplicant and the authentication server. Each supplicant attempting to access the network is uniquely

identified by the authenticator by using the client’s MAC address. While AP is setup as Auto, only Wireless client supported 802.1x client can access the network.

● Re-Authentication

The administrator can enable periodic 802.1x client re-authentication and specify how often it occurs. When re-authentication time out, Authenticator will send

EAP-Request/ Identity to reinitiate authentication process.

In ZyXEL Wireless AP 802.1x implementation, if you do not specify a time period before enabling re-authentication, the number of seconds between re-

authentication attempts is 1800 seconds (30 minutes).

● EAPOL (Extensible Authentication Protocol over LAN)

Authenticators and supplicants communicate with one another by using the Extensible Authentication Protocol (EAP, RFC-2284). EAP was originally designed to

run over PPP and to authenticate dial-in users, but 802.1x defines an encapsulation method for passing EAP packets over Ethernet frames. This method is referred

to as EAP over LANs, or EAPOL. Ethernet type of EAPOL is 88-8E , two octets in length. EAPOL encapsulations are described for IEEE 802 compliant

environment, such as 802.3 Ethernet, 802.11 Wireless LAN and Token Ring/FDDI.

The EAP protocol can support multiple authentication mechanisms, such as MD5-challenge, One-Time Passwords, Generic Token Card, TLS and TTLS etc.

Typically, the authenticator will send an initial Identity Request followed by one or more Requests for authentication information. When supplicant receive the EAP

request, it will reply associated EAP response. So far, ZyXEL Wireless AP only supports MD-5 challenge authentication mechanism, but will support TLS and

TTLS in the future.

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