The PIX has customized licensing to enable or disable features to fit the administrator's needs. Features differ depending on the activation key. The activation key allows the administrator to enable features without acquiring new software. The activation key is computed by Cisco using the feature matrix and serial number. The serial number is based on the flash, so if the flash is replaced, the activation key must be replaced. The activation key enables feature-specific information such as interfaces, high availability, and type of encryption.

The show version command can be used to get information about the activation key. It shows the code version, hardware information, and activation key information. The show activation-key can also be used.

Serial Number: 480090153 (0x1c9d9829)   Running Activation Key: 0x75fe7c49 0xc08b4082 0x08979930 0xe4b4c4b0Licensed Features:Failover:           EnabledVPN-DES:            EnabledVPN-3DES:           DisabledMaximum Interfaces: 6Cut-through Proxy:  EnabledGuards:             EnabledURL-filtering:      EnabledInside Hosts:       UnlimitedThroughput:         UnlimitedIKE peers:          Unlimited

The flash activation key is the same as the running key. This machine is a PIX 515 and has an unrestricted license, with the maximum number of...