I think you can set up a video camera pretty much anywhere you want, but there are a lot of laws about audio recording. I would check on your state's laws. I don't even think this would be covered by 1-party consent.
The front porch is a "public" area, in the sense that there's no expectation of privacy. It's as legal as if you were taking an iphone video or live photo of your car in the driveway and happened to catch the neighbor in the background.
Ring does have the ability to set "blackout zones" in the camera's FOV, and as a good neighbor the ring owner could have excluded the neighbor's driveway/porch with a few clicks.
The front porch is a "public" area, in the sense that there's no expectation of privacy.
Parent commenter is correct. The laws in your area are not the laws in every area. Some states and cities have restrictions on recording, even in public areas.
Illinois is one of the states with laws that prohibit many kinds of incidental audio recordings, while video is allowed. As was explained to me by a downstate communications lawyer, it's because the laws were passed by mobbed-up politicians before video was a thing, in order to protect mobsters from federal investigations.
Even today, when you see undercover recordings taken by local TV news stations in Illinois, there's never any audio.
According to this article [0] by the senior counsel and ethics officer for the Illinois Department of Central Management Services,
> The threshold questions are whether the conversation is private, and whether the recording is done secretly. The law allows recording if the conversation is not private, that is, there is no reasonable expectation of privacy as defined above. Also, there is no violation unless the recording is “surreptitious,” defined as “obtained or made by stealth or deception, or executed through secrecy or concealment.”
You cannot record voice in Illinois for example. I'm pretty sure this is the case for most all party consent states.
If you post a video with voice online you are breaking the law in Illinois, unless all parties gave you consent. I don't even know how something like RING camera is legal since it is being uploaded to the cloud and the parties don't consent to it.
Edit: Illinois actually made some changes to the law, that allows recording of voice in public spaces.
