With the release of Communications Manager 11.5SU3 there is a change in licensing specific to encryption. The reason for this change is the need to meet certain export and regulatory requirements. Since the license file will be issued from Cisco directly to a user/customer they’ll have better control and visibility who is enabling mixed mode. I think the visibility part will be important for Cisco to understand how few customers are running mixed mode. Maybe that will encourage them to make some needed changes?

So what happens when you upgrade to 11.5SU3 and you have mixed mode enabled? You’ll get a warning that’ll you need to add an encryption license to Prime License Manger. Mixed mode will not be disabled on your cluster by installing this patch.

How do you get the license? Over at the product upgrade tool at the Cisco site you can use your contract or Spark calling subscription to obtain the $0 license CUCM-PLM-ENC-K9=. Install the issued license on Prime License Manager and synchronize with Communications Manager.

I encourage you to comment on this post as other technical details are discovered. It’s still unknown if there is a time limit on running mixed mode without this installed license file. Thanks!

Reference:
Cisco UCM Release Notes
CUCM Readme