Extreme Networks Altitude 3500 Series, Product Reference Manual

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Altitude 3500 Series Access Point Product Reference Guide
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KeyGuard Encryption
Use KeyGuard to shield the master encryption keys from being discovered through hacking. KeyGuard
negotiation takes place between the access point and MU upon association. The access point can use
KeyGuard with Motorola MUs. KeyGuard is only supported on Motorola MUs.
For detailed information on KeyGuard configurations, see “Configuring KeyGuard Encryption” on
page 181 .
Wi-Fi Protected Access (WPA) Using TKIP Encryption
Wi-Fi Protected Access (WPA) is a security standard for systems operating with a Wi-Fi wireless
connection. WEP’s lack of user authentication mechanisms is addressed by WPA. Compared to WEP,
WPA provides superior data encryption and user authentication.
WPA addresses the weaknesses of WEP by including:
●
a per-packet key mixing function
●
a message integrity check
●
an extended initialization vector with sequencing rules
●
a re-keying mechanism
WPA uses an encryption method called Temporal Key Integrity Protocol (TKIP). WPA employs 802.1X and
Extensible Authentication Protocol (EAP).
For detailed information on WPA using TKIP configurations, see “Configuring WPA/WPA2 Using
TKIP” on page 183 .
WPA2-CCMP (802.11i) Encryption
WPA2 is a newer 802.11i standard that provides even stronger wireless security than Wi-Fi Protected
Access (WPA) and WEP. Counter-mode/CBC-MAC Protocol (CCMP) is the security standard used by the
Advanced Encryption Standard (AES). AES serves the same function TKIP does for WPA-TKIP. CCMP
computes a Message Integrity Check (MIC) using the proven Cipher Block Message Authentication Code
(CBC-MAC) technique. Changing just one bit in a message produces a totally different result.
WPA2-CCMP is based on the concept of a Robust Security Network (RSN), which defines a hierarchy of
keys with a limited lifetime (similar to TKIP). Like TKIP, the keys the administrator provides are used to
derive other keys. Messages are encrypted using a 128-bit secret key and a 128-bit block of data. The
end result is an encryption scheme as secure as any the Altitude 35xx provides.
For detailed information on WPA2-CCMP, see “Configuring WPA2-CCMP (802.11i)” on page 185 .
Firewall Security
A firewall keeps personal data in and hackers out. The Altitude 35xx’s firewall prevents suspicious
Internet traffic from proliferating the access point managed network. The Altitude 35xx access point
performs
Network Address Translation (NAT) on packets passing to and from the WAN port. This
combination provides enhanced security by monitoring communication with the wired network.
For detailed information on configuring the access point’s firewall, see “Configuring Firewall Settings”
on page 188 .