PrizmDoc Application Services (PAS) is a service that provides application-level logic for the Viewer; such as enabling document viewing through the PrizmDoc Server, saving and loading of markup, and handling opening of documents and creating viewing sessions. This service is designed to be a gateway between the Viewer and PrizmDoc Server.
The PrizmDoc Application Services are intended to run on the same server as your web tier, although that is not required. As it is a standalone service, it can run anywhere between your web application and PrizmDoc Server, including on its own separate machine if necessary.
For more information, refer to the Developer Reference - PAS RESTful API.