Technical data

Encryption Support

Meru Wireless LAN System offers CCMP-AES for WPA2 and TKIP for WPA. A key differ-

ence between WPA and WPA2 is the underlying encryption method. For WPA2 it is

CCMP/AES and for WPA it is TKIP/RC4. Descriptions of these technologies are

provided in this section. Meru also supports the original 802.11encryption protocols

provided by WEP64 and WEP128.

We recommend using the more secure CCMP, or the TKIP encryption solution if your

site’s client hardware cannot support CCMP.

CCMP-AES

AES is the Advanced Encryption Standard and is used by the US Department of

Defence as a replacement for older encryption standards. As such, it is very secure.

AES can be used in several modes, and CCMP is the mode used by WPA2. Both terms

are commonly used interchangeably.

TKIP

As part of the WPA solution to address the weaknesses in WEP, WPA uses Temporal Key

Integrity Protocol (TKIP) to improve upon WEP security by expanding the size of the

encryption key and Initialization Vector (IV), increasing the number of keys in use,

and creating a message integrity check.

TKIP is a Layer 2 encryption algorithm that uses a 128-bit key and a 64-bit IV. TKIP

uses the RC4 algorithm along with a symmetrical key to produce encrypted text. The

symmetrical key is used for encrypting and decrypting packets, and can be automat-

ically distributed to an AP and from there to the user station when 802.1X EAP is

implemented. TKIP key management system uses one of a possible 500 trillion keys

to uniquely encrypt each data packet. TKIP uses the Message Integrity Check (MIC),

a function that computes and compares a per-packet integrity check to ensure the

content of the packets have not been modified by an outside source during packet

transmission. If the sent/received checksums do not match, the packet is assumed to

be tampered with and dropped.

To configure TKIP, see the section Configure WPA With the CLI.

WEP Security Features

Wired Equivalent Privacy (WEP64 and WEP128) is a Layer 2 security protocol specified

in the IEEE Wireless Fidelity (Wi-Fi) standard, 802.11. WEP is designed to provide a

wireless LAN with comparable level of security and privacy to what is usually

expected of a wired LAN. A wired LAN is generally protected by physical security

mechanisms, such as controlled access to a building, that are effective for a

controlled physical environment. However, such security mechanisms do not apply to