The 3.1 software is an upgrade service pack.
The software upgrades can be downloaded from CCO and are available to users with SMARTnet support contracts.
Sensor software upgrades download site:
http://www.cisco.com/kobayashi/sw-center/ciscosecure/ids/crypto/
The sensor software license is covered under the standard SMARTnet contracts for the sensor appliance hardware, no additional contract is needed for the sensor software.
Refer to the IDS-4235 data sheet and Cisco pricing tool for the available SMARTnet contracts and prices.
http://www.cisco.com/warp/public/cc/pd/sqsw/sqidsz/prodlit/ids4f_ds.htm
NOTE: The sensor SMARTnet contract covers all software running on the IDS-4235 as well as the IEV (Intrusion Detection Event Viewer) that can be downloaded from the sensor, installed on a Win 2K box, and be used to monitor up to 3 sensors.
The sensor SMARTnet contract does not, however, cover the software licensing for the enterprise level (5+ sensor monitoring) IDS management tools like the Unix Intrusion Detection Director and the Cisco Secure Policy Manager (sold as part of VMS bundle).
A separate software support contract needs to be purchased for the enterprise level IDS management software products.
See the following links for the enterprise level IDS management tools:
http://www.cisco.com/warp/public/cc/pd/sqsw/sqidsz/prodlit/1560_pp.htm
http://www.cisco.com/warp/public/cc/pd/wr2k/vpmnso/prodlit/1506_pp.htm
