Internet - CCTV Connectivity ??

Hi to all who read this little problem I have. Don't know if I'm posting in the right section but iif I am, apologies beforehand. I have 350 speed package with vm, the internet has been spot on until recently when the wifi kept dropping out for 5-10 minutes at a time, along with the desktop , which is ethernet connected. I disconnected all my ethernet devices and... yes you've guessed it, the internet was fine. I re-introduced each of the ethernet devices over the days and each posed no problems till I introduced the cctv ethernet. Low and behold the internet blobbed out...... I therefore changed ALL the ethernet cables from cat 5 to cat 6A. This has been fine and dandy till this morning (sun 11th) when the problem raised its head again and the internet dropped out.. As soon as I pulled the cctv ethernet from the router the internet came back on, this is where my problem lies, what else can I do to find the fault on the cctv system as I am stuck,. Internet is fine without cctv but drops out with it connected.. Any suggestions or help on this matter would be gratefully received , thanks in advance to all who read this..

What type of Internet connection do you have and what is happening to the router lights?

It depends on how deep you want to dig, and how comfortable you are with network configurations. The most informative but most effort is to set up a network monitor like fiddler on your LAN and see what messages your CCTV system sends out. This should show you what messages are sent when your router goes down.

To avoid some of this effort, it will help to share what brand your CCTV system is and what your configuration is. Somebody here may have similar setup and may have encountered your problem.

On my network, all CCTV cameras and the recorder are on a seperate VLAN, which has no access to my router. But that is because I do not trust chinese CCTV cameras, and I do not trust the apps that come with them that allow you to monitor you cameras over the internet.

A wild guess, but have a look if any of your CCTV kit is set up as a DHCP server and is creating duplicate IP adresses

I would check and if necessary change the Ip address of each camera as it sounds as if you have a conflict.

Still guessing wild, without knowing what your network looks like, there is a possibility that you you create a loop in your network when you plug in your CCTV system. Look up 'broadcast storm' to find out what happens when you create network loops. If you have a switch in your network and it has an ethernet route back to itself when you connect the CCTV system. Broadcast messages, like DHCP request, can get repeated and multiplied till they overload your router. The loop can also consist of a WiFi and an ethernet branch