Most homes nowadays don't come with pre-installed network infrastructure, and many homeowners find that installation of wiring and wall plates is economically out of reach - not to mention that all of this typically requires a small equipment room. So, what do you do when you want to install a home control system or stream audio/video across the house?
One of the cornerstones of any home network is a wireless router. The router can be purchased on the cheap and connected to your cable/DSL modem via its WAN port. You now have a WiFi connection to the internet, and if the router is a multi-port variety, you can connect hardware (PCs, control devices, etc) directly to the router in the same room. Many internet users already have this setup, and it's ideal for single PC and laptop users.
But what if you need internet/network in another room and the WiFi is out of range? Or you need a hardwired network connection to a device in another room? This is where a wireless repeater comes in handy. The repeater essentially boosts the WiFi signal and provides a connection for another network switch (make sure you check the specs for this feature). You locate the repeater in the desired room, connect to the switch, and you now have a wired network in that room - integrated with your home network. The repeater may also boost your WiFi signal for greater coverage in your home. Ensure that all wireless devices share the same SSID and encryption (WEP works best). Also check manufacturer requirements to confirm that all wireless devices can communicate with each other.
How does this work in the real world? In my home, the DSL enters through the front bedroom. I needed a wired connection for my Blu-Ray player in the living room. I setup a repeater in the entertainment center and configured it to communicate with my home WiFi, connected its network port to a 4-port switch, and connected the switch to the the Blu-Ray.
When I stream in a NetFlix movie, the data travels from the DSL modem to the 4-port wireless switch in the bedroom, over the air to the repeater in the living room, to the 4-port switch in the entertainment center, to the Blu-Ray player, and presto! We have streaming without running new cable in the attic or punching holes in drywall for connection boxes. This strategy should also work for just about any controlled device that requires a wired connection.