Motorola Solutions WiNG 5.2.6 Reference Manual page 277

5. Define the Key Settings.
Pre-Shared Key
6. Define Key Rotation values.
Unicast messages are addressed to a single device on the network. Broadcast messages are addressed to multiple
devices. When using WPA2, a wireless client can use 2 keys: one unicast key, for its own traffic to and from an access
point, and one broadcast key, the common key for all clients in that subnet.
Motorola Solutions recommends rotating these keys so a potential hacker would not have enough data using a single
key to attack the deployed encryption scheme.
Unicast Rotation
Interval
Figure 6-5 WLAN Security - WPA/WPA2-TKIP screen
Enter either an alphanumeric string of 8 to 63 ASCII characters or 64 HEX
characters as the primary string both transmitting and receiving authenticators
must share. The alphanumeric string allows character spaces. The access
point converts the string to a numeric value. This passphrase saves the
administrator from entering the 256-bit key each time keys are generated.
Define an interval for unicast key transmission in seconds (30 -86,400). Some
clients have issues using unicast key rotation, so ensure you know which kind
of clients are impacted before using unicast keys. This feature is disabled by
default.
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