When you spin up an Windows EC2 instance, you need to license Windows whether you BYOL or license through AWS. This base license allows a maximum of two concurrent users, in order to go beyond the initial two connects you would need to purchase RDS CAL (Remote Desktop Services Client Access License) from Microsoft; They have pricing model per seat/user and per device, I’m not sure if both can apply to a Windows instance with AWS or not.
So if you intend to setup your hosts in a High Density mode, you’ll have the cost of
- EC2 Instance
- Windows License (If you use BYOL, otherwise it is included in the EC2 cost)
- Windows RDS CAL
- UiPath Robots
I think determining your risk tollerance, operational management overhead, and acceptable cost will determine which way you want to go, not having looked into the costs of CALs it very well might be more cost effective or at least offset by increasing your EC2 instance sizing and minimizing the number of instance you deploy.
I’ve setup a shared host for Studio before with using development/studio robot license when Studio is connected to Orchestrator as well as a single named studio license when not connected to Orchestrator. I can’t give a definite answer on mixing of Attended/Unattended and Studio/Developer studio, technically it is possible I’ve mixed Development and NonProduction (Unattended) in testing, If you run Studio on a host that is a non-developer robot, it will present you with a warning about it not being the intended usage (This was with 2018.3, not sure what behavior 2019.10 would give you).
If you wanted to do something similar for Attended vs Studio… this would all depend on the use case of the user, if you have some users that will not be using Studio, you’d licence their runtime with Attended, but if they would also run Studio, they’d need to be licensed for that. I would reach out to UiPath support on the technical limitations and TOS if that can be achieved as you’re thinking. (In practice, I haven’t thought about Developers also being the benefactors of attended Robots or if you can use Studio license as a production oriented work.)