First off, by and large the entities you speak of do not own the broadcast affiliates. They may air their content on them a few hours a week (20-30 hours) but the rest of the content is determined by the owner of the station(s). As for up time, if your job does not include maintaining the application the server is running, and you can ping it, then you're doing your job and it's up. It's a matter of perspective. The end user may see it as down time, but not on your watch. The "server uptime" would be fine. The application is another matter. As for a broadcaster, maintaining a signal is the engineer's uptime. If some other equipment is faulty, that too could be included. However, if it is something related to traffic, then engineering wouldn't be accountable. I'll even play devil's advocate and say that the operator on duty should catch any issues, but even then if traffic made an error not much can be done.