I have multiple sites, and a persistent site-to-site VPN combined with on-demand VPN (for use while traveling on random wifi hotspots to boost security).
Before we go that route:
- do you need to monitor the multiple sites all the time or only occasionally (i.e. "check on them" like before and after a major storm)?
- do you have adequate remote site upload speed to handle streaming camera video (I only get about 2FPS on 3 cameras over 3Mb upload), figure out the upload speed for each remote site. (download doesn't matter for this use case, the cameras video streams will be going "up" via this internet connection).
- do you have adequate download speed to handle receiving the streams from all sites without drastically degrading your local performance for Netflix etc. (i.e. if 3 remote sites are streaming 10 Mb each, can you absorb the constant consumption of 30 Mb on your download pipe at the "local" or "central" location)?
- can you put equipment at each site (I recommend each remote site is an OpenVPN server, and your central site "connects" to them as a client). I use an ASUS router, and it's been up for two years even through multiple storms and power outages it has recovered. I haven't tried PiVPN so unsure how reliable it would be, which is paramount concern for me as the site is 1000 miles from my "local" location.
- do you have some system at the local site that can act as OpenVPN client and make the persistent connection.
For upload speed you might have to do a
speed test from the site, as some providers have gotten clever about hiding this detail from subscribers (like Comcast offers "1200 Speed Internet", which only tells you the max download speed, and probably has something pathetic like 30-50Mb upload).
If you had "25/5 cable internet", you have an asymmetrical 25 Mbit upload and 5Mbit download (5Mb would be the important number). Almost 100% of the time the smaller number is the upload bandwidth. If you happen to have a symmetrical 10Mb, 100Mb, or 1000Mb connection then you have the same speed in both directions (theoretically). I have had
both asymmetrical fiber (10/3 & 50/30) and
symmetrical fiber (1000/1000).