AirPort Utility 6.x: If your base station or AirPort Time Capsule is connected to a router providing NAT and DHCP
If your base station or AirPort Time Capsule is connected to a router or other network device that’s using Network Address Translation (NAT) to share a single Internet connection with multiple computers on your network, and you’re using Dynamic Host Configuration Protocol (DHCP) to provide private IP addresses, you need to turn off NAT and DHCP on the base station or Time Capsule and set it up as a bridge.
Most networks need only one device using NAT and DHCP to provide IP addresses.
- Open AirPort Utility, located in the Utilities folder in the Applications folder. Select the base station you want to set up, then click Edit.
- Click Network, and then choose Off (Bridge Mode) from the Router Mode pop-up menu.
With NAT and DHCP turned off, the base station acts as a simple bridge between the wired and wireless computers on the network.