connecting a dsl modem to a 4 port router
I’m having some problems connecting an adsl modem to a 4 port router (both dlink boxes).
I take the dlink router ( D-Link DI-704UP ) back to office to test with my ADSL system.
Before I get a chance to properly test the router, my ADSL modem/router ( netcomm nb1300 plus 4 ) fails after 13 months (it had a 12 month warranty… grrr). So I quickly buy a single eth port router ( billion bipac 5102s ) & I connect it to my existing router (tp-link tl-wr642g, 4 eth ports, 1 wan port & a wireless AP).
I then notice that my original setup (the connection to the wireless router) doesn’t look right. It works, but the wireless router has 4 eth ports & a wan port & I didn’t connect the wan port to the original modem. The modem was connected to the second router via one of the standard ethernet ports on both boxes.
I decide to look into this further, as I might encounter many similar situations.
With next to no information available on the internet (or in the manuals) on how to connect an adsl modem & a router… I experiment a bit & I find 2 different ways to connect them:
How it should work: modem is set to bridge mode & then connected to the wan port of the router… The modem should now ignore its ISP details (I’m assuming a PPPoe internet connection, which requires a username & password). It should also ignore its DHCP & firewall settings. Now I enter isp details (username & password) into the router & make sure the router firewall settings, DHCP, etc, are appropriate. I can now connect 4 computers to the 4 router ports. The router is logging in to the ISP, with the modem acting as a conduit for the network traffic
Messy workaround: modem is set to router mode (make sure the DHCP server, firewall, etc., are enabled). The modem needs the PPPoe username and password. Connect it to one of the 4 ethernet port on the router (NOT to the wan port)… Make sure the routers (fixed) IP address is set to be in the same subnet as the modems IP address & DHCP pool eg: modem is 192.168.0.1, dhcp pool is 192.168.0.3 – 192.168.0.34, so change router IP address to something like 192.168.0.111. Now, disable DHCP on the router… let the modem do the dhcp allocations.
Reboot all devices & computers. Note that this time, the modem is acting as the nat firewall (instead of the router).
advantage: works with modems that don’t have a bridge mode (ie will work with all adsl modems)
disadvantage: you lose 1 ethernet port… so only 3 computers can connect instead of the usual 4.
Anyway, I take the router back to the customer & find that his modem doesn’t have a bridging function (but it allows for NAT to be switched on & off… not sure why)… So I setup the system the “messy” way, and setup shared windows drives.
There is a slight hiccup with being able to view the “program files” folder, but I put it down to an interaction problem between winxp pro and winxp home.
I leave it for the moment, as I also want to setup the print server function that is available with the router (it has a usb port).
I install the printer server software from the router CD, and then what? The manual is no help, & I don’t know how to print to the print server. I eventually decide to just connect the printer locally & share it out, so that the other computer can also print to it. Not as nice as using the print server function, but it works & its quicker than trawling the ‘net for an answer.
Update (June 2008 ): I’ve since found that most modern routers will now operate correctly by plugging the modem into the WAN port of the router. Very little else needs to be done… but some manufacturers still have WAN ports that don’t function correctly (particularly when isolating DHCP and IP addresses.
I have Motorola SB5100 cable modem, and TP link WR642g router/AP. When I plug in modem on WAN port, and set up connection (on wr642) like PPPoE couldn’t connect to internet. In the log of wr642 I have info like “faild chap authentification”. Also try to clone MAC address of my modem to wr642, but I have the same. It only works if the modem is on LAN port and each pc in the network have PPPoE conection. I update firmware of the router but it’s the same. It looks like router doesn’t support MSChap protocol which my ISP using.
any sugestion would be great.
regards aleks (bosnia & herzegovina)
Hello alek,
Looking at the router specifications, it doesn’t mention chap compatibility, so I’d
say you are right: router doesn’t support mschap.
I’d avoid cloning MAC addresses… it can cause lots of problems, if you end up with
2 devices that use the same mac address… and its very difficult to figure out whats
happening.
I’d say you don’t have much choice but to plug the modem into the lan port.
Can’t help much with what you need to do with your PC’s, & pppoe, as cable internet
isp’s all seem to have different ways of authenticating & transferring data.
hi, i recently bought a tl-wr642, but have tried connecting in various ways many times, but doesn’t seem to work. Can someone help me connect and setup and use the router properly. thanks.
Daniel,
that’s a bit vague, more info needed. eg: write up 1 way that you tried. don’t skip any steps.
Hi Daniel.
As you can gather, setting up routers and modems can be very difficult (I enounter new models every month)…
Its also not the kind of thing that can be explained over the internet, or over the phone.
You need to get an expert to configure it correctly.
If you are in the northern Brisbane area, then call me, and I’ll arrange a time to visit and fix things.
I might even be able to help out is you are southside…
Luigi
hi, ok here are the steps:
1. First I installed the adsl modem with the ethernet cable to the WAN at the back of the router, and then connected another ethernet cable from pc to the LAN of the router. The pc tries to connect but then nothing happens. So I put a wireless adaptor on the pc. The wireless adaptor is receiving the signal from the wireless router with excellent signal, but I still can’t connect??
actally i dont know if i have the same problem but here it goes.
i have a compex adsl modem MRL21A and a wifi router TPLINK WR542G. the problem is that when i connect the model directly to my com ots ok but when i try to plug the cable to the WAN or LAN port on the router a cant establich a connection. my router cant connect with the modem i tried everything i could, as far as i know. could anybody help me? i type the pass and login without any mistakes but still i cant connect with the modem. this a scrshot of my router status
http://img86.imageshack.us/my.php?image=beznazwyan1.jpg
as you see there is online time saying 0 and a connect button that doesnt work ;P i dont have a slightest idea what to do so please help!!!!
thx in advance
Hello koziro.
I don’t know about the modem. i’ve not heard of it before.
I’m assuming your ISP is not doing something strange (like running special software on your PC, which might get blocked once you go via the router).
As I said in my original post, if you cannot set the modem to bridge mode (now days, many seem to handle wan ports automatically), then plug the modem into an ethernet port… then you shouldn’t need to press the tplink WAN connect button (its all done via the modem.
You also need to try ping, and see where the block is, (and make sure the PC, router, and modem are setup with DHCP correctly).
Failing that, you need to post screenshots of all menus for the router, modem, and PC network settings. You haven’t given enough info for anyone to truly help you.
oki i will try do that 🙂 i hope to do it corectly
Nowadays, most routers seem to handle these situations much better.
They usually have 5 ethernet ports at the back:
One is labelled WAN, or modem, and it plugs into the adsl modem
The other 4 ports (usually labelled LAN), are connected to the computer(s).
Usually, there is nothing else to do.