Viper Setup Wizard Step:  

Encryption Enabled  Disabled

Viper uses AES-128-bit encryption to protect your data from eavesdropping and to prevent intruders from changing your configuration. Use of encryption is optional but we strongly recommend it for actual networks. The encryption phrase and key must be common to all units in a given network

Encryption Pass Phrase
Encryption Key

Note:
The symbol indicates that this parameter will require a 'Reset' before it takes effect.