So far the Session license is RTU license, however as per the datasheet it can be enforced in future version.
Which version you use depends on your existing setup, you may go with 11.X version.
On the CCW we have 10.X, 11.X and 12.X version available for ordering.
How do I license my SME??
SME requires no license, you can simply add the CUCM server to your ELM / PLM server and that would be it, if for any reason you want to use the co-res ELM / PLM to handle only SME, you can order a "SME License" which will be a license with just a few users in it so your SME is considered to be in a valid licensing situation.
For 9.X/10.X SME systems â€“ no software or node licenses are required, and session licenses are issued as RTU certificates (paper licenses). A SME 9.X/10.X does not require physically installed licenses. However, a SME 9.X/10.X is required to be managed by a registered Enterprise License Manager (ELM) or Cisco Prime License Manager (Cisco Prime LM)
A customer can add a SME system to their product inventory for an ELM/Cisco Prime LM already registered for the customerâ€™s existing CUCM or CUC systems.
A customer can request to register a separate ELM/Cisco Prime LM â€“ only for their registered SME. This is done by contacting firstname.lastname@example.org and requesting licenses to register there SME ELM/Cisco Prime LM. A nominal amount of UCL Essential licenses will be issued in order to register a separate ELM/Cisco Prime LM used only for SME.