Help connecting two buildings wirelessly to make one big wireless LAN

[littlebeartoe]

I've been scouring the web and this forum for help on this but can't get it working...

I have two stone buildings on my property. They're about 150 feet apart, I can't run CAT5 between them, and I want to share my wireless LAN across both buildings, especially to use just one ISP account. A friend advised me to use my two Linksys WRT54Gs (router+access points with four ports) and then get two WAP54Gs (access points only). In theory, one WRT54G acts as the connection to the cable modem, as the DHCP server, and as a dedicated connection to the other WRT54G in the other building, and in each building, the WAP54Gs act as the LAN broadcasters to the computers in each building.

In detail, here's my understanding of how to do it:

(1) In one building (BLDG1), connnect one WRT (WRT1) to the cable modem, configure it as the only router and DHCP server, put it in ad-hoc mode, restrict it with MAC address filtering to only connect to the other WRT (WRT2) in the other building (BLDG2), connect WRT1 to a good outdoor omni-directional antenna, and set it to use its own radio channel (I'm using 6) in order to minimize interference.

(2) Connect one WAP54G (WAP1) to one of the four regular ports (NOT the one "uplink" one) on WRT1. Set it to use a unique channel (I'm using 1). Otherwise, I've left WAP1's default settings.

(3) In BLDG2, connect WRT2 to the Yagi antenna, disable DHCP on it, set it to use channel 6 in order to talk to WRT1, and put it in a-hoc mode.

(4) Connect the other WAP54G (WAP2) to a regular port on WRT2, set it to a third channel (I'm using 11), and leave other settings as defaults.

Well, it isn't working. I seem to have a good signal between the two antennae, but I'm getting IP address conflicts and other issues. In fact, it's failing right at step (2) above-- even with all network devices in BLDG2 turned off, when I connect WAP1 to WRT1, the LAN works briefly, and then Windows gives me that little "there is an IP conflict" error, and pretty soon the LAN goes down. I think that may be the only thing really wrong here, but I can't be sure.

Questions:

* Does my topology look right?

* Why not use the WAPs as the ad-hoc connectors (virtual wireless cables) between the two buildings instead of the WRTs? Does it matter?

* Have I mis-configured anything, or left out major configuration steps?

Thanks in advance for any help!

--Bob Ellison
Holicong, PA

[YeOldeStonecat]

I'd suggest looking into third party DD-WRT firmware for the wrt54g units...I've bridged using that before.

Your routers and APs all have unique IP addresses? Not left on defaults?

[littlebeartoe]

YeOldeStoneCat, thanks for the quick response. I actually do have DD-WRT on one of the WRT routers. It seems quite powerful, but the docs are woefully inadequate.

Anyway, I think I resolved the IP conflict last night (not sure quite how!), and half of my network is now running correctly. I'll try later today to get the other building hooked up. I think that will be a lot easier than the first part, now that I've learned where the stumbling blocks are.

I'll post my resolution if/when it works. If anyone has guidance, please send it! This challenge (hooking up two buildings) is becoming increasingly common for suburban/country homeowners like me who have limited IT chops.

--Bob

[YeOldeStonecat]

YeOldeStoneCat, thanks for the quick response. I actually do have DD-WRT on one of the WRT routers. It seems quite powerful, but the docs are woefully inadequate.

DD-WRT has a very rich wiki...quite a few articles on bridging..such as this one.
http://www.dd-wrt.com/wiki/index.php/Wireless_Bridge