Accessing to IP cameras behind TL-MR3020 nano router

Question

What I want to do is connecting several IP cameras to my LAN with wireless router/AP.

I have a main USRobotics modem/router/AP (192.168.1.1) and all my computers are connected to that one using 192.168.1.* subnet and DHCP (with pool from 192.168.1.4 to 192.168.1.99).

I would like to connect 3 IP cameras (with static IPs 192.168.1.100,101,102) to a switch (cheap, simple 8 port switch) and the switch to TPLink MR3020 nano router (192.168.1.254) with cable. And at the end I want MR3020 to connect my main USRobotics with wireless.

And I would like to access IP cameras from the computers? How can I do that?

MR3020 only have one ethernet port and wireless interface. I have stock firmware on MR3020 but if it's not enough, I can setup OpenWRT or DD-WRT on it.

Below you can see the sample diagram.
^{Click for full size}

Answer 1

You did not specify how you configured MR3020 router, but it seems like the WAN interface will connect to your USR router wirelessly.

In this case, you have to put your MR3020 router and IP cameras to a different subnet (i.e. 192.168.2.*). Then you can setup port forwarding on your MR3020 to forward specific ports to each camera individually. The WAN port of MR3020 must be assigned to a static IP (i.e. 192.168.1.253). This way you can access each camera by accessing your MR3020 WAN IP and ports you specified.

Example (I'll use port 80 on your cameras as an example) of MR3020 port forwarding list:

   1080 -> 192.168.2.100:80
   1081 -> 192.168.2.101:80
   1082 -> 192.168.2.102:80

This way you can access camera 100 using 192.168.1.253:1080, camera 101 using 192.168.1.253:1081, and camera 102 using 192.168.1.253:1082

If you do MR3020 as a bridge, then you can keep your cameras in the same subnet 192.168.1.* and access them directly from your PCs.