Cisco SL-4320-SEC-K9= software license/upgrade 1 license(s)

You can use the security licenses to activate the advanced security features offered on the Cisco 4000 Series ISR platform. You may order these part numbers only for the universal image that supports payload cryptography. The HSEC license is required for a feature to have full crypto functionality. Without the HSEC license, only 225 secure tunnels and 85 Mbps of crypto bandwidth would be available.