Professional Access Point Administrator Guide

Field

Description

Enable pre-authentication

If for WPA Versions you select WPA2 or Both, you can enable pre-authentication for

 

WPA2 clients.

 

Click Enable pre-authenticationif you want WPA2 wireless clients to send pre-authen-

 

tication packet. The pre-authentication information will be relayed from the access

 

point the client is currently using to the target access point. Enabling this feature

 

can help speed up authentication for roaming clients who connect to multiple

 

access points.

 

This option does not apply if you selected WPA for WPA Versions because the orig-

 

inal WPA does not support this feature.

 

 

Cipher Suites

Select the cipher you want to use from the list:

 

TKIP—Temporal Key Integrity Protocol (TKIP) provides a more secure encryption

 

solution than WEP keys. The TKIP process more frequently changes the encryp-

 

tion key used and better ensures that the same key will not be reused to encrypt

 

data (a weakness of WEP). TKIP uses a 128-bit temporal key shared by clients

 

and access points. The temporal key is combined with the client's MAC address

 

and a 16-octet initialization vector to produce the key that will encrypt the data.

 

This ensures that each client uses a different key to encrypt data. TKIP uses

 

RC4 to perform the encryption, which is the same as WEP. But TKIP changes

 

temporal keys every 10,000 packets and distributes them, thereby greatly

 

improving the security of the network.

 

CCMP (AES)—Countermode/CBC-MAC Protocol (CCMP) is an encryption method for

 

IEEE 802.11i that uses the Advanced Encryption Algorithm (AES). It uses a CCM

 

combined with Cipher Block Chaining Counter mode (CBC-CTR) and Cipher Block Chain-

 

ing Message Authentication Code (CBC-MAC) for encryption and message integrity.

 

Both—The default. When the authentication algorithm is set to Both, both TKIP

 

and AES clients can associate with the access point. Clients configured to use WPA

 

with RADIUS must have one of the following to be able to associate with the access

 

point:

 

• A valid TKIP RADIUS IP address and RADIUS Key

 

• A valid CCMP (AES) IP address and RADIUS Key

 

Clients not configured to use WPA with RADIUS will not be able to associate with

 

access point.

 

 

Authentication Server

Select one of the following from list:

 

Built-in—To use the authentication server provided with the Professional Access

 

Point. If you choose this option, you do not have to provide the Radius IP and

 

Radius Key; they are automatically provided.

 

External—To use an external authentication server. If you choose this option you

 

must supply a Radius IP and Radius Key of the server you want to use.

 

Note: The RADIUS server is identified by its IP address and UDP port numbers for

 

the different services it provides. On the Professional Access Point, the RADIUS

 

server User Datagram Protocol (UDP) ports used by the access point are not con-

 

figurable. The Professional Access Point is hard-coded to use RADIUS server UDP

 

port 1812 for authentication and port 1813 for accounting.

 

 

Security - 118

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USRobotics Instant802 APSDK manual Enable pre-authentication, Improving the security of the network