Professional Access Point Administrator Guide

Field

Description

WPA Versions

Select the types of clients you want to support:

 

WPA—If all clients on the network support the original WPA, but none support the newer

 

 

WPA2, then select WPA

 

WPA2—If all clients on the network support WPA2, USRobotics suggests using WPA2,

 

 

which provides the best security per the IEEE 802.11i standard.

 

Both—If you have a mix of clients, some of which support WPA2 and others which sup-

 

 

port only the original WPA, select Both. This option lets both WPA and WPA2 clients

 

 

associate and authenticate, but uses the more robust WPA2 for clients who support it.

 

 

This WPA configuration allows more interoperability, at the expense of some security.

 

 

Cipher Suites

Select the cipher you want to use from the list:

 

TKIP—TKIP(Temporal Key Integrity Protocol) is the default.

 

 

TKIP provides a more secure encryption solution than WEP keys. The TKIP

 

 

process more frequently changes the encryption 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—When the authentication algorithm is set to Both, both TKIP and AES cli-

 

 

ents can associate with the access point. WPA clients must have one of the fol-

 

 

lowing to be able to associate with the access point:

 

 

• A valid TKIP key

 

 

• A valid CCMP (AES) key

 

Clients not configured to use a WPA-PSK will not be able to associate with the

 

access point.

 

 

 

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USRobotics Instant802 APSDK manual WPA Versions, Cipher Suites