Proxim AP-4000 用户手册

SSID/VLAN/Security

• EAP-Tunneled Transport Layer Security (TTLS): Certificate-based authentication (a certificate is required on the 

server; a client’s username/password is tunneled to the server over a secure connection); supports automatic key 
distribution

• PEAP - Protected EAP with MS-CHAP: Secure username/password-based authentication; supports automatic key 

distribution

Different servers support different EAP types and each EAP type provides different features. See the documentation that 
came with your RADIUS server to determine which EAP types it supports.

There are three main components in the authentication process. The standard refers to them as:

1. Supplicant (client PC)
2. Authenticator (Access Point)
3. Authentication server (RADIUS server)

When the Security Mode is set to 802.1x Station, WPA Station, or 802.11i Station you need to configure your RADIUS 
server for authentication purposes.

Prior to successful authentication, an unauthenticated client PC cannot send any data traffic through the AP device to 
other systems on the LAN. The AP inhibits all data traffic from a particular client PC until the client PC is authenticated. 
Regardless of its authentication status, a client PC can always exchange 802.1x messages in the clear with the AP (the 
client begins encrypting data after it has been authenticated).

The AP acts as a pass-through device to facilitate communications between the client PC and the RADIUS server. The 
AP (2) and the client (1) exchange 802.1x messages using an EAPOL (EAP Over LAN) protocol (A). Messages sent from 
the client station are encapsulated by the AP and transmitted to the RADIUS (3) server using EAP extensions (B).

Upon receiving a reply EAP packet from the RADIUS, the message is typically forwarded to the client, after translating it 
back to the EAPOL format. Negotiations take place between the client and the RADIUS server. After the client has been 
successfully authenticated, the client receives an Encryption Key from the AP (if the EAP type supports automatic key 
distribution). The client uses this key to encrypt data after it has been authenticated. 

For 802.11a and 802.11b/g clients that communicate with an AP, each client receives its own unique encryption key; this 
is known as Per User Per Session Encryption Keys.

Wi-Fi Protected Access (WPA) is a security standard designed by the Wi-Fi Alliance in conjunction with the Institute of 
Electrical and Electronics Engineers (IEEE). The AP supports 802.11i (WPA2), based on the IEEE 802.11i security 
standard.