RDS Cal licenses for session manager workgroup server

[Shahzad_Asif]

We need to buy RDS Cal licenses for our PAM solution that have a session management component that actually is accessed via RDP when a user wants to target his system via PAM. We need to license those session management servers (3 windows 2019 servers as workgroup) with RDS Cal. Earlier we considered User base licenses but came to know that it will not work for workgroups (must be for domain based systems). If we now go for device based RDS Cal, how many licenses we would need for 3 systems that will be accessed via RDP by  

[#2]

Should be one per client device.

License your RDS deployment with client access licenses (CALs) | Microsoft Learn

[#3]

@Dave Patrick Thank you for your feedback. So in case if we have 15 users connecting from 15 workstations we must need at least 15 per device licenses for RDS to apply on the RDP server. We may add some buffer as some users may establish another session. Is it the right understanding? 

[#4]

Yes, sounds correct. Please don't forget to mark helpful replies.