What is a Wireless Key?

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Getty Images/Peter Dazeley

A wireless key is a type of password commonly used on Wi-Fi wireless computer networks to increase their security.

WEP, WPA and WPA2 Keys

Wi-Fi Protected Access (WPA) is the primary security standard used on Wi-Fi networks. The original WPA standard was introduced in 1999, replacing an older standard called Wired Equivalent Privacy. A newer version of WPA called WPA2 appeared in 2004.

All of these standards include support for encryption  - the ability to scramble data being sent over a wireless connection so that it cannot easily be understood by outsiders.

Wireless network encryption utilizes mathematical techniques based on computer-generated random numbers. WEP uses an encryption scheme called RC4, which the original WPA replaced with Temporal Key Integrity Protocol (TKIP). Both RC4 and TKIP as used by Wi-Fi were eventually compromised as security researchers discovered flaws in their implementation that can easily be exploited by attackers. WPA2 introduced Advanced Encryption Standard (AES)  as a replacement for TKIP.

Each of RC4, TKIP and AES utilize wireless keys of varying lengths.  Thes wireless keys are hexadecimal numbers that vary in length - typically between 128 and 256 bits long - depending on the encryption method used. Each hexadecimal digit represents four (4) bit of the key. For example, a 128-bit key can be written as a hex number of 32 digits.

Passphrases vs. Keys

passphrase is a password associated with a Wi-Fi key. Passphrases can be a minimum of 8 and up to a maximum of 63 characters in length.

Each character can be an uppercase letter, lowercase letter, number or symbol. The Wi-Fi device automatically converts passphrases of varying lengths into a hexadecimal key of the required length.

Using Wireless Keys

To use a wireless key on a home network, an administrator must first enable a security method on the broadband router.

Home routers offer a choice among multiple options usually including

  • WEP
  • WPA
  • WPA2-AES

Among these, WPA2-AES should be used whenever possible.  All devices connecting to the router must be set to use the same option as the router, but only very old Wi-Fi equipment lacks AES support. Choosing an option also prompts the user to enter either a passphrase or a key. Some routers allow entering multiple keys instead of just one to give administrators more control over adding and removing devices from their networks.

Each wireless device connecting to a home network must be set with the same passphrase or key set on the router. The key should not be shared with strangers.

Setting up WPA requires creating a hexadecimal number and entering that number into the Wi-Fi settings of each device belonging to the same network.