Heres some snippets from http://www.jiljiklen.com/linux/dd-wrt.html of how to bridge to your 360, it worked fine once I flashed the firmware on my router and followed the bolded directions below. I researched it here before starting too just in case. http://www.dd-wrt.com/wiki/index.php/Installation
You should do research before doing certain things, because after you install the firmware you have to wait 3 minutes after there's no indication of whats going on, or you could ruin your router. I tried to set it up with other peoples info, but I googled some more and these directions worked on the first try (what I have bolded)
From WRT Wiki http://www.dd-wrt.com/wiki/index.php/Wireless_Bridge
Wireless Bridging is used to connect two LAN segments via a wireless link. The two segments will be in the same subnet and look like two Ethernet switches connected by a cable to all computers on the subnet. Since the computers are on the same subnet, broadcasts will reach all machines, allowing DHCP clients in one segment to get their addresses from a DHCP server in a different segment. You could use a Wireless Bridge to transparently connect computer(s) in one room to computer(s) in a different room when you could not, or did not want to run an Ethernet cable between the rooms. Contrast this with Client Mode Wireless, where the local wireless device running DD-WRT connects to the remote router as a client, creating two separate subnets. Since the computers within the different subnets cannot see each other directly, this requires the enabling of NAT between the wireless and the wired ports, and setting up port forwarding for the computers behind the local wireless device. Segments connected via Client Mode Wireless cannot share a DHCP server.
My motivation: I wanted to get my XBox online (and on-LAN) from another room, without running Ethernet to it. WDS was out of the question unfortunately because one of my routers was a late-model WRT54G and as such wasn't (at the time) easily modified. I had an extra WRT54G lying around that could run DD-WRT. Alternatively I could have bought a proper Linksys or Microsoft solution to connect the XBox to the existing WiFi, but what's the fun in that?
* Primary Router (Internet Connection): WRT54G V5 — stock Linksys firmware — 192.168.1.1
* Secondary Router (For the Bridge): WRT54G V3 — DD-WRT V23 SP1 Firmware — 192.168.1.1 — which I changed to 192.168.1.2 in my setup
(I'm guessing that the Primary Router could be any make and model of wireless router as we're not doing anything to it!)
My Primary Router has 128bit WEP Encryption enabled. It does NOT have Wireless MAC Address Filtering enabled. We will assume you want your Secondary Router to become 192.168.1.2.
1. Log into the Secondary Router. (We will only be altering the Secondary Router!)
2. Administration Tab — Factory Defaults Subtab
1. Restore Factory Defaults: Yes
2. Click "Save Settings" — triggers reboot.
3. Router's IP will now be 192.168.1.1 if it wasn't already.
This was a very important step. I have run this process 3 times now as a trial, and the instructions are written assuming you have a "clean" router.
3. Setup Tab — Basic Setup Subtab
1. Connection Type: Disable
2. STP: Disable
3. Local IP: 192.168.1.2 (it was initially 192.168.1.1)
4. Assign WAN Port To Switch: Checked
5. DHCP Server: Disable
6. Click "Save Settings" — triggers reboot.
I had an error along the lines of "Can't connect to 192.168.1.1" — This is because it's now 192.168.1.2 — close and restart the browser to avoid authentification problems and connect to the new IP address and retype your username and password.
4. Security Tab — Firewall Subtab
1. SPI Firewall: Disable
2. Click "Save Settings"
5. Wireless Tab — Basic Settings Subtab
1. Wireless Mode: Client Bridge
2. Wireless Network Mode: Match your primary router.
3. Wireless Network Name (SSID): Match your primary router. (case matters!)
4. Wireless Channel: Match your primary router.
5. Wireless SSID Broadcast: Disable
6. Click "Save Settings"
6. Wireless Tab — Wireless Security Subtab
1. Security Mode: Match your primary router, I used WEP (I have not tried anything but 128bit WEP!) WPA-PSK works as well -guyonphone; WPA-PSK even works if original router is WPA2 mixed -mcoope3; v2.3_sp2 in client bridge mode currently doesn't support WPA2-PSK, but only WPA2-PSK mixed mode, so the AP has to be set to mixed and not WPA2-only mode (it can be either AES or TKIP).-zevnik
To put it simple, WPA2 doesn't work in Bridge Mode currently (dd-wrt v23 sp2)-teekay
2. Encryption: Match your primary router.
3. Key 1: Match your primary router.
4. Click "Save Settings"
7. Wireless Tab — Advanced Settings Subtab
1. Authentication Type: Shared Key
2. Click "Save Settings"
This seems like a VERY important step — it DID NOT work until I did this! (worked for me on auto, when using WEP -cheesetoast)
8. Status Tab — Wireless Subtab
1. Click Site Survey and join the appropriate wireless network. Access Point table should show the MAC address of your Primary Router, along with signal strength. (SSID Broadcast MUST be enabled on your primary router) At this point it was working 100% for me.
If that worked, then:
9. Administration Tab — Backup Subtab
1. Click "Backup"
(SAVE this config before doing anything else to your router, just in case!)