Using a wireless access point as an AP client

April 19, 2008 7:56 AM

Connecting with your own wireless access point (AP) to another one that provides access to the Internet -- help me figure out the basics here.

My neighbour upstairs owns an AP (it's the D-Link WDL2100AP). He wants to put it in use when his own Internet connection is down, so that he can temporarily browse the Web via other APs in the area that are open to acess (a site survey shows several).

Problem is he doesn't know how to do that; I was asked to help -- I can hack my way through wireless routers & static IPs, etc. but wireless access points... I'm not too savy with.

I've read the WDL2100AP's manual (zipped PDF file) and searched Google for possible set-ups, but I'm still left with lots of questions.

I obviously need to set the AP (the "local AP") to "AP Client" mode and point it to another open (un-secured) AP (from hereon referred to as "remote AP"). I guess it would also help if the remote AP served IP addresses automatically (DHCP) -- let's assume that's the case here.

On the local AP front, if I'm to enable the "DHCP server" option (so that machines on my side) can get IPs automatically from it, any hints on what the values for "Gateway", "Wins" and "DNS" should be? (screenshot)

[Note: the local AP also allows me to enable the "DHCP client" option but that would be a no-no, I think, since -- as the Quick Install Guide (zipped PDF file) suggests -- I can only access the AP's configuration page when its IP is set (statically) to "192.168.0.50", the Subnet mask to "255.255.255.0" and my IP (again, statically) to "192.168.0.x". So, "DHCP" client is probably better "disabled" right?]

Finally, (assuming again we're dealing with a remote AP that's open to access and serves IP via DHCP) is this how it's supposed to work? i.e. pair the computer with local AP, set it to "AP Client" mode, choose a remote AP and you're done -- you've got access to the Internet.

Or am I missing something? (And I can't help but wonder: what happens if the remote AP doesn't serve IP address via DHCP? How do I have to adjust the local AP's settings?)

Thanks a ton for reading this far -- and thank you in advance for your help and any clarifications you may have (I'm pretty certain I've got several things wrong in my description above).

posted by kchristidis to Computers & Internet (6 answers total)

Maybe I'm missing something here, but is there some reason he can't just select one of the other access points from his client machine when he needs to?
posted by JaredSeth at 8:19 AM on April 19, 2008

Unless I am misunderstanding you, what your neighbor wants to do is set up his access point to act in "bridge mode" [that's your googleable term] with another access point so that he can gain access via his (presumably wired?) connection plugged in to another open wired/wireless access point. Do I have that correct? Have you looked at tutorials about how to do this? Have you tried doing this yet? If so, what happened? If not, why not?
posted by jessamyn at 8:30 AM on April 19, 2008

Response by poster: Jared: his client machine (without the "help" of the local AP) can only see 2 or 3 remote APs (none of them are open, BTW). With the "help" of the local AP he can see several dozens of remote APs.

Jessamyn: "bridge mode" was a term I wasn't really familiar with, so thank you for that tip (looking into that link that you gave me, as we speak.) For the record, he's connected wirelessly to the local AP (it's located on the top of the building).

Please keep the tips/feedback coming -- I appreciate it.
posted by kchristidis at 8:41 AM on April 19, 2008

Response by poster: I've read the tutorial jessamyn gave me, and it seems like it applies more-or-less to our case.

Question though: I see no "Client Bridge" mode in the WDL-2100AP. These are the modes it supports (and also WDS only works with other APs of the same model). How do I proceed?

Thanks!
posted by kchristidis at 9:04 AM on April 19, 2008

See if the router in question is compatible with the open-source DD-WRT firmware. This firmware drastically expands the functionality of wireless routers and supports bridge mode with ease. Good luck!
posted by expletivization at 1:27 PM on April 19, 2008

Response by poster: expletivization: thanks, I may have a look at this as well. (Though I'd like to avoid hacking the firmware -- remember, it's not my AP!)
posted by kchristidis at 2:43 PM on April 19, 2008