Yes. My setup is actually a bit more involved. The DVR of the surveillance camera setup is connected via ethernet to a regular home router, also powered by the rig's 12v. And from the tow vehicle, I connect to the router with my tablet and run the app that came with the system. I do have mobile internet (Mobley) but this connection does not require the internet connection to run, as it's just a direct wi-fi connection between my tablet and the router. There is a slight but noticeable latency (less than a quarter of a second) for the video so I also have an extended sideview mirror on the driver's side mirror, but I've never really had to have a split second reaction. As is, I can see things approaching from pretty far and with the 360 degree awareness, I can anticipate the traffic very well so the latency has never posed a problem for me.

The router is connected to my mobile internet while parked and every portable devices connect to it. The router also can connect to a USB external hard drive and that can have movies and other stuff that the connected devices have access to.

edit: forgot to tell you the brand. It's Nightowl brand I got from Costco for $150 I think. But Any wired or wireless home surveillance system works. Powering it is just getting a 12v pigtail from Amazon. Power it off in storage though because it will run down your battery. I went with wired because it was cheaper and also because I gutted the interior so running the cables was simple. And aside from the security, it records all the campsite shenanigans we get into, like the kids playing and us having a BBQ. It's actually kinda nice to be able to catch some of those moments. We caught some critters wandering around at night too.