NIST helps make WLANs more secure
Connecting state and local government leaders
The Institute of Electrical and Electronics Engineers' 802.11i wireless security standard, released almost two years ago, is a whopping 174 pages long (not counting acknowledgements, etc.).
The National Institute of Standards and Technology's Guide to IEEE 802.11i, Special Publication 800-97, released in draft form this week, is 156 pages long (including appendices, etc.).
Between the two of them, network admins have the tools they need to build highly secure wireless networks for their government agencies--provided they can get through the documents. If you have to pick just one to help with your WLAN, pick NIST's. Not only does it highlight what agencies specifically need to know to comply with things like the Federal Information Security Management Act, it's a far better read.
Some of the highlights:
NIST is laser-focused on the concept of "robust security networks," created under 802.11i through "robust security network associations" among wireless devices, access points and authentication servers. In a nutshell, RSNs employ authentication and encryption to establish secure, trusted communications over WLANs. Agencies need to be using RSN.
Not all authentication techniques are created equal. As NIST point out, RSNs use the Extensible Authentication Protocol for authentication, but because its extensible by definition, EAP varies from platform to platform. Not only should an agency's WLAN EAP work with what it already has in place, but it has to support cryptographic keys, otherwise it's non-compliant.
Not all cryptography is created equal. It's not really news, but NIST explicitly describes why agencies need to use the Cipher Block Chaining Message Authentication Code Protocol and not the Temporal Key Integrity Protocol (both are part of 802.11i). Basically, the former uses a Federal Information Processing Standards-approved cryptographic algorithm, namely the Advanced Encryption Standard.
NIST endorses the Wi-Fi Alliance, an industry group that took it upon itself to perform WLAN compatibility testing when no one else was. The Wi-Fi Alliance created Wi-Fi Protected Access 2 to describe wireless products that implement 802.11i security protocols. According to NIST:
"Federal agencies should procure WPA2 products that use FIPS-approved encryption algorithms and have been FIPS-validated. Organizations that plan to use authentication servers as part of their IEEE 802.11 RSN implementations should procure products with the WPA2 Enterprise level certification. Also, because the WPA2 certification is expanded periodically to test for interoperability with additional EAP methods, organizations should obtain the latest WPA2 information before making procurement decisions."
Previously, the Defense Department also mandated Wi-Fi Alliance-approved products. As recently as last year, we would have worried about leaving compatibility testing to industry, paticularly when it came to security. WPA2 seemed a little slow to ramp up and it was unclear who would get their products through the labs first and why.
But WPA2 kicked in big time as 2005 progressed. As of March 2006, when the alliance made WPA2 mandatory in all its approved products, there were more than 600 WPA2 products to choose from.
NIST isn't naive. It realizes not all agencies waited for 802.11i to build WLANs, and achieving the kind of security NIST describes in this document could require buying all new WLAN gear. Therefore, NIST states, "For legacy IEEE 802.11 equipment that does not provide CCMP, auxiliary security protection is required; one possibility is the use of an IPsec VPN, using FIPS-approved cryptographic algorithms."
When it comes to securing pre-802.11i WLANs, NIST's older guidance, Special Publication 800-48, "Wireless Network Security: 802.11, Bluetooth and Handheld Devices," still applies.
Posted by Brad Grimes