Those reviews are fools that have no idea what they are doing LOL.
I have those cameras and have never needed outside network access to set them up!
In fact I set them up on an old laptop that doesn't even touch the internet.
From a previous post I did in the event you are not well versed:
No need really to update to latest firmware as they should have came with the best firmware, which may not be the latest. Something to keep in mind. Most of us do not update firmware if the camera is working for our needs as it usually breaks something.
You need to set up each camera one at a time. Do not plug in all at once as they all come with an IP address of 192.168.1.108 and you will IP conflict them if you plug them all in at the same time.
It is recommended you get a second NIC to put all the cameras on one NIC that is isolated from the internet.
Here is how most of us get the cameras to the IP address of our system:
The default IP address of the camera is 192.168.1.108, which may or may not be the IP address range of your system.
Unhook a computer or laptop from the internet and go into ethernet settings and using the IPv4 settings manually change the IP address to 192.168.1.100
Then power up your camera and wait a few minutes.
Then go to
INTERNET EXPLORER (needs to be Explorer and not Edge or Chrome with IE tab) and type in 192.168.1.108 (default IP address of Dahua cameras) and you will then access the camera.
Tell it your country and give it a user and password.
Then go to the camera Network settings and change the camera IP address to the range of your system and hit save.
You will then lose the camera connection.
Then reverse the process to put your computer back on your network IP address range.
Next open up INTERNET EXPLORER and type in the new IP address that you just gave the camera to access it.
OR use the IPconfig Tool, but most of us prefer the above as it is one less program needed and one less chance for the cameras to phone home.