A wireless router can also be used to segregate wireless computers from wired computers in your network. In this manner, you can prevent file and printer sharing and any other type of direct contact between the wired and wireless computers.
Why would you set a network up this way? Sure, you can keep the wired computerrs from accessing the wireless ones, but what does that accomplish? Add a comment or answer in my blog
You won’t be able to use any of the printers on the wired network from a computer on the wireless network or vice versa. Similarly, you won’t be able to share files either way.
You set up this network very similarly to the way you would to protect the wireless computers from the wired computers. You just reverse the order of the wired and wireless routers.
The first part of trick to segregating the networks is to connect the WAN (Wide Area Network) port on the wired router to a LAN (Local Area Network) port on the Cable/DSL modem. That’s the same connection you’d make with a wireless router, if you were only using it or were wanting to protect the wired computers from the wireless computers.
This connection will cause the Wireless router to get its IP address assigned by the upstream network’s DHCP server (typically, a cable Internet Sevice Provider or a DSL provider).
The DHCP server within the wireless router should be ON for this setp, as we’ll use it to assign IP addresses to the wireless computers and to the wired Cable/DSL router.
Then, connect the WAN port on the wireless router to a LAN port on the wired router. This will make the wireless router get its "upstream" (WAN) IP address from the wired router.
The DHCP server within the wireless Cable/DSL router should also be turned ON. It should also be set to a different IP address range than that being used by the Wired router. Linksys normally has these set differently by default: the wireless router uses 192.168.1.x/255.255.255.0, while the wired router uses 192.168.0.x/255.255.255.0.
The bottom line of this configuration is that the wired computers will be unable to route any connection attempts past the WAN port on the wireless router. The wireless computers should not be able, but may be able, to initiate connections to (and get responses from) the wireless computers.
Tech Tip
Routers should not send outbound any requests that are attempting to contact one of the IP address ranges that are reserved for private networks (e.g., 192.168.x.y/255.255.0.0); however, manufacturers of consumer-grade home routers may not implement that block.
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