There’s no direct REST API query to get this, but it is possible. “If the viewers are connecting directly to the Wowza Server for playback then each viewer has its own session and with e.g. a custom module you could obtain the IP address of that viewer. That won’t work if you’re distributing your stream via a CDN though.” (Please see post: Can I check if the person watching the video is watching it?)
Once you know the session id, then you can create an HTTP Provider which will obtain the IP address:
This is the part of the HTTP provider code sample you want to look at:
ret.append("");
ret.append(""+httpSession.getSessionId()+"");
ret.append(""+httpSession.getIpAddress()+"");
Full code and tutorial is here:
https://www.wowza.com/docs/How-to-get-detailed-server-info-with-an-HTTP-Provider