HomeTechnicalconnecting a dsl modem to a 4 port router


connecting a dsl modem to a 4 port router — 10 Comments

  1. 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)

  2. 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

    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.

  3. 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.

  4. Daniel,

    that’s a bit vague, more info needed. eg: write up 1 way that you tried. don’t skip any steps.

  5. 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…


  6. 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??

  7. 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

    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

  8. 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.

  9. 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.