How to connect 2 existing separate networks together via ethernet

The 2 separate networks are 192.168.1.xx and 192.168.3.xx. Network 1 is WAN connected to a Fiber 1 Gbps modem. Both routers are Netgear R7000 AC1900 models.
Both routers are currently set for DHCP and address from 192.168.x.5 to 192.168.x.254. The 192.168.3.x router supports multiple wireless cameras and an NVR, all with fixed addresses.
The requirement is: For users on network 1 to connect to the cameras and NVR on network 3. I don't need the reverse capability.
I would appreciate guidance on making the necessary changes to the routers to make this connection work.
 

Gabriel Pike

Posts: 287   +79
This is covered in the manual for these devices. Pages 90-93.
This is from the manual:
Custom Static Routes Typically, you do not need to add static routes unless you use multiple routers or multiple IP subnets on your network. As an example of when a static route is needed, consider the following case:
• Your main Internet access is through a cable modem to an ISP.
• Your home network includes an ISDN router for connecting to the company where you are employed. This router’s address on your LAN is 192.168.1.100.
• Your company’s network address is 134.177.0.0. When you set up your router, two implicit static routes were created. A default route was created with your ISP as the gateway, and a second static route was created to your local network for all 192.168.1.x addresses. With this configuration, if you try to access a device on the 134.177.0.0 network, your router forwards your request to the ISP. The ISP forwards your request to the company where you are employed, and the company firewall is likely to deny the request. In this case you must define a static route, telling your router to access 134.177.0.0 through the ISDN router at 192.168.1.100.
Here is an example:
• The Destination IP Address and IP Subnet Mask fields specify that this static route applies to all 134.177.x.x addresses.
• The Gateway IP Address field specifies that all traffic for these addresses will be forwarded to the ISDN router at 192.168.1.100.
• A metric value of 1 works because the ISDN router is on the LAN.
• The Private check box is selected only as a precautionary security measure in case RIP is activated.
Set Up a Static Route To set up a static route:
1. Launch a web browser from a computer or mobile device that is connected to the router network.
2. Enter http://www.routerlogin.net. A login window opens.
3. Enter the router admin user name and password. The user name is admin. The password is the one that you specified the first time that you logged in. The user name and password are case-sensitive. The BASIC Home page displays.
4. Select ADVANCED > Advanced Setup > Static Routes. The Static Routes page displays.
5. Click the Add button. The page adjusts.
6. In the Route Name field, type a name for this static route (for identification purposes only).
7. To limit access to the LAN only, select the Private check box. If the Private check box is selected, the static route is not reported in RIP.
8. To prevent the route from becoming active, clear the Active check box. In some situations, you might want to set up a static route but keep it disabled until a later time. By default, the Active check box is selected and a route becomes active after you click the Apply button.
9. Enter the following settings:
• Destination IP Address. Enter the IP address for the final destination of the route.
• IP Subnet Mask. Enter the IP subnet mask for the final destination of the route. If the destination is a single host, enter 255.255.255.255.
• Gateway IP Address. Enter the IP address of the gateway. The IP address of the gateway must be on the same LAN segment as the router.
• Metric. Enter a number from 1 through 15. This value represents the number of routers between your network and the destination. Usually, a setting of 2 or 3 works, but if this is a direct connection, set it to 1. 10. Click the Apply button. Your settings are saved. The static route is added to the table on the Static Routes page.

Good luck.
 
Unfortunately my 86 year old non-network-trained mind cannot associate the lengthy material with my current request. I was hoping for a more explicit set of instructions but maybe this particular setup will not work without additional hardware or software or not at all. I will try and locate a local network person to help this ol buzzard through the procedure!