Automating WSTEP enrollment requires installing a PKIaaS Virtual Machine on your premises.
Permitted use of the PKIaaS Virtual Machine
You may use PKIaaS Virtual Machine for integrating the on-premises Windows infrastructure of a User with your cloud-based PKIaaS instance. You may only use PKIaaS Virtual Machine in connection with your validly licensed use of Entrust PKIaaS. You are expected to keep reasonable records relating to at least the number of copies of the software that you have made, used and distributed, and the environments where they have been deployed.