Avaya AP-4 User Manual page 209

Security
1. Click Configure > Security > Authentication.
2. Set Authentication Mode to WPA-PSK.
3. Enter a Re-keying Interval.
— The Re-keying Interval determines how often a client's
encryption key is changed and can be set to any value
between 60 and 65535 seconds. Rekeying frustrates hacking
attempts without taxing system resources. Setting a fairly
frequent rekey value (900 seconds=15 minutes) effectively
protects against intrusion without disrupting network activities.
4-114 Avaya Wireless AP-4/5/6 User's Guide