We have a telephony platform, and we are looking to change the presence status of Lync users, based on events in the telephony platform. We would prefer to use the UCWA REST api, as we are familiar with REST api's and have most of the infrastructure in place already.
Checking the documentation, it quickly becomes apparent that a user can set its own presence. However, we don't want to keep track of the authentication information for every single user. Instead, can some users (presumably an administrator-like user) alter the presence status of other users using UCWA? Any other practical possibilities for managing the presence-status of Lync users externally?
Via an answer I provided on the MSDN Forums: Can UCWA be used to set the presence-information for an other user on the Lync platform?
Simple Answer:
This is not possible in UCWA as the logged in user (endpoint) does not have privileges to take those type of actions.
Is it possible another way Answer:
You could make use of UCMA and create a Trusted Application which would allow creation of a UserEndpoint which would not need to know the user's credentials to make changes to their presence data. You would need to wrap this logic into a Web API and connect it to your specific application/scenario.