I have my main computer with Cable Modem and D-Link Wireless Router on one end of my house. Because the router is on one side of the house, the bedrooms get no signal. I am new to networking and from what I understand, I need to set up a wireless access point somewhere in the middle of the house.
What that article is describing is how to take a second wireless router and reconfigure it so it's ONLY a wireless AP (it no longer does any routing). Of course, you could instead buy a standalone wireless AP (it would have a single LAN port that you could connect to a LAN port on your wireless router), but many ppl choose to use a wireless router and simply reconfigure it for these purposes, if only to save money (they may already have an older, otherwise unused wireless router sitting in their closet!).
[wireless router #1](lan)<-- wire -->(lan)[wireless router #2 - ap mode]
I will use your "[wireless router #1](lan)<-- wire -->(lan)[wireless router #2 - ap mode]" if you dont mind.
Would I set up a wireless network broadcasting from "wireless router #1" as well as "wireless router #2 - AP mode"?
If I understand this correct, I can set up both with the same SSID and security, but just change the channel frequency so they are 6 or more channels apart. This will allow me to "roam" correct?
Yes, both wireless APs broadcast their respective SSIDs. It would only make sense for them to use different channels, although technically they would work using the same channel, but less efficiently. And the only non-overlapping channels on the 2.4GHz freq are 1, 6, and 11, so those are ideal.
As far as the SSID itself, using the same SSID does provide a pseudo form of roaming. I say “pseudo” because unlike a cellular network that would actually transfer you to another cell long before the connection was lost, your wireless client will NOT. It will cling to the current wireless AP until it’s lost, even if a stronger signal comes into range. It’s simply a limitation of wireless networking. It can’t preserve context from AP to AP, so rather than risk losing the current context, it holds it until it simply can’t any longer.