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Simple Router question

  1. Nov 6, 2007 #1
    Simple Router question ....

    Hi all, I searched the internet for some clues but couldn't find anything very precise. I have a wireless router/access point attached to a phone line and it works fine. It transmits the radio signal carrying internet to my laptop and all ok. I can access the web from the laptop. I can just plug in the power and phone line jack to the wireless router and it works perfectly even without the desktop PC.

    I also have a fixed DSL router attached to the desktop PC and can access the ADSL line through the fixed router, no problem. I would like to get rid of this fixed ADSL router and just use the wireless router for both. I would like to have the wireless router behave exactly as the fixed router, so when I turn on my desktop PC I can connect to the DSL line and at the same time the wireless signal is being transmitted, I can surf the web from the laptop.

    I read that this is something that is complex to do. I just want to get rid of the fixed router, plug in the wireless router in its place and just have one box for all my needs, both wireless and / or fixed DSL line for the desktop PC. Can it be done easily ?

    I read that the fixed router has DSL parameters that the wireless router may not have or that cannot be programmed, but if the wireless router attaches to the DSL line and connects to the internet, can't I just bypass any of the parameters from my desktop PC, can't they just be ignored since the wireless connects anyways ? Thanks for any help or clues!
  2. jcsd
  3. Nov 6, 2007 #2


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    I'm not sure what you mean by "fixed DSL router", but i think you are referring to the DSL modem. You will need this to dial into your ISP to use their services. You have not mentioned the type of router you have. The only way I can see you to eliminate the need is to get one of those modem-routers combinations. Even then, I'm not sure it would work as some ISPs require special modem setup.
  4. Nov 6, 2007 #3
    Thanks alot Ranger. Yes the fixed router is a modem - router (or maybe it is just a modem) for DSL aka cable modem. The wireless router - modem is a ADSL2+ modem, router,ethernet switch, wireless access point all in one. The WL 154 Sitecom router.

    The wireless router connects perfectly to the internet and ADSL and transmits perfectly to laptop. So I imagine that all the necessary parameters are ok inside the router. I just want to get rid of my fixed cable - modem and use this wireless router for everyhing.

    I tried a few times but can't get it to access the internet from my desktop PC even though it transmits the internet to my laptop. Is there something blocking it from having access to the internet through the desktop PC ? I am using an ethernet cable to this wireless router (just as I used it to configure the wireless part: then admin then PPPoE then VCI, VPI etc. ). Is there some simple configuration that must be made to let the desktop PC see the internet through this router ?
  5. Nov 6, 2007 #4


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    Is the wireless router actually have a router?
    If it just a wireless access point and a DSL modem then it will only connect so a single client. You need a router and NAT (network address translator) which gives each of your internal machines a separate IP address and manages sorting external packets coming into your single address onto whichever internal machine requested it.

    Normal sequence is to plug your ADSL device into the router and it has the wifi hub.

    If your ADSL devices is USB only then a windows PC (at least the XP-pro/Vista super-doublepluspgood) can also do the routing for you (see internet connection sharing) but you need to leave it switched on and have 2 network cards, or a wired and wireless card.

    Otherwise just buy a $50 Dlink wireless router.
  6. Nov 6, 2007 #5
    Yes it is also a router. So I think I have to set this router with DHCP enabled so that it furnishes an IP address to the desktop PC and another address to the laptop. It automatically defaults to dynamic NAT. There is a choice of single or multiple IP for NAT, which should I choose ?

    Thanks for any other clues! It seems like just a few choices and this single box which has a modem-router and wireless access point all in one should be able to connect my desktop PC to the DSL line and transmit the internet to both desktop and wirelessly to the laptop at the same time. Any other ideas ? thanks anyways.
  7. Nov 6, 2007 #6


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    DHCP helps, but you can always set the PCs addresses yourself.
    I have only heard of multiple IP NAT with high end routers that share multiple incoming lines for failover/load balancing - not sure what it means otherwise.

    If the box was supplied by the cable co - it could be set to not allow conection sharing, but then it wouldn't include a NAT.
    Does it have a wired network socket? You could try that with a simple $10 hub and see if the NAT is working or if it is a wireless problem?
  8. Nov 6, 2007 #7
    How will the desktop be accepting wireless? I don't see the problem here so long as your desktop can accept wireless connections. A wireless adapter card for the desktop may be necessary.
  9. Nov 7, 2007 #8
    No I want the desktop to pick up the normal internet through the wireless router using the wireless router's LAN connection. The desktop has a LAN cable connected to a LAN port on the wireless router, but at the same time I can receive the radio signal transmitted by the wireless router from a laptop.

    I just want to use this one box that seems to have everything, router, wireless access point etc. all in one and replace the wired router furnished by the cable company with this one box. It already does go on the internet using the ADSL of the cable company and transmits it wirelessly to the laptop. Why can't that same signal go on the LAN and reach my desktop ?
  10. Nov 8, 2007 #9
    If laptop is getting internet fine then its just settings. But i'm comfused, you seem to have a ADSL (broadband through telephone line -UK probably BT) AND DSL (seperate cable coming through put in by cable company- Virgin/NTL/Telewest/Sky)??
  11. Nov 9, 2007 #10
    No I just have the ADSL coming through the telephone line. The telephone company gave me their router to connect and it works fine. I just want to replace their router with this wireless ADSL router that has everything contained in one box. The wireless router does in fact connect to the telephone company and transmits the ADSL singal to the laptop.

    I just am trying to use the LAN ethernet port on this router connected to a port (through the ethernet cable J45) on my desktop PC and ALSO recieve the internet on my desktop. What parameters of the LAN side of the wireless router must be configured ? I think I just have to set DHCP enabled so this wireless router gives out dynamic IP addresses to both the laptop and the desktop, and that should be all I need. Do I have to set DNS and RIP1 and NAT in any particular way ? Thanks for any possible clues.
  12. Nov 9, 2007 #11
    It shouldn't make any diffenence, but on my setup (same as your trying to do) i had trouble with the RJ45 cable, i had a patch but should have had a crossover.
    What make of router/wireless/momdem/thingy are you using?
  13. Nov 9, 2007 #12
    Sitecom WL 154. Shouldn't any ethernet cable be the same since the 4 ports on the wireless ADSL router modem are for ethernet LAN and connect to the LAN of PC ?

    Do I have to set DNS and RIP1 and NAT in any particular way ?

    Thanks anyways.
  14. Nov 9, 2007 #13
    I'm not sure oldtobor but it sounds like you're having the same problem as I had in reverse(mine was with a third wireless connection) check your MAC addresses to see that your desktop isn't trying to take one that has already been assigned(I had to go to 6 before I found a free one
    http://www-dcn.fnal.gov/DCG-Docs/mac/index.html [Broken]
    try here to find out the mac address
    or if in windows type 'cmd' in RUN and then 'ipconfig' at the prompt
    check you're LT too to see if they ain't both trying the same MAC
    Last edited by a moderator: May 3, 2017
  15. Nov 10, 2007 #14
    Hi oldtobor,

    I've had the same problem some time ago. I tried DHCP and it didn't work
    for some reason. That is why I've set a static IP for my PC.

    For setting a static IP for your PC do the following:


    1) Download the manual for your Sitecom WL 154 router here (first dowload link).
    Go to page 9 of the PDF manual (chapter 1.2 "Configuring PC in Windows XP").
    There, follow steps 1 to 4:

    Step 1: In Windows XP, go to Start / Settings / Control Panel. In the Control Panel double-click
    on Network and Dial-up Connections.

    Step 2: Double-click Local Area Connection

    Step 3: In the Local Area Connection Status window click on

    Step 4: Select Internet Protocol (TCP/IP) and click Properties.


    2) Having done steps 1 to 4 go to step 5,
    but instead of clicking on "Obtain an IP address automatically",
    click on "Use the following IP address".


    3) Make the following entries:
    IP address: (according to the manual on page 8 you can use an IP in the range of to

    Subnet mask:

    Default gateway: (That is the IP of your router)


    3b) optional - only if you have further desktop PCs:
    If you have a further desktop PC make the following entries:

    IP address:
    Subnet mask:
    Default gateway:


    4) Below "Default gateway" click on "Use the following DNS server addresses".
    Make the following entry:

    Preferred DNS server: (That is the IP of your router)
    (Leave the field behind Alternate DNS server blank.)


    5) Restart computer. As mentioned by mufcdiver, you can then check
    with "ipconfig" whether the configuration was successful.
    See http://www-dcn.fnal.gov/DCG-Docs/mac/xp.html [Broken].


    6) You should now be able to connect to the internet with your desktop PC via the WL 154 router.

    6b) If not, you may have to tell your router that your PC's ip address is
    (Look in the router settings)

    I hope this helps.
    Please tell me if step 6b was necessary.

    You can leave the networks settings for your laptop on DHCP.
    Last edited by a moderator: May 3, 2017
  16. Nov 10, 2007 #15
    Problem solved. I actually didn't have to do anything at all, the desktop pc and the laptop through wireless both connect now. I just set the normal wireless part of the router with the usual information admin,admin and then the PPPoE etc. and that is all. The desktop also connects, it is always obtain address automatically etc.

    I will keep in mind all the information above anyways for any future problems or experiments, thanks.
  17. Nov 11, 2007 #16
    Hi oldtober,

    I'm glad that you have access now.
    To secure your WLAN do the following:

    1) Change the username and password for the router. Don't leave it at "admin", "admin".
    Otherwise people with a WLAN laptop can access your router's settings.

    2) Change the SSID (currently "Sitecom") to a different name, e.g. oldtober_2.
    See page 20 of the manual.
    The first time I used WLAN I had a bad connection between router and laptop.
    I suppose it was because several neighbours had the same SSID and the laptop got "confused".

    3) Set "Broadcast SSID" to NO (The SSID is the name of your router). By doing so nobody can "see" your router. But you have to manually set on your laptop that the router's name is now oldtober_2.

    4) Change "Authentication Type" to WPA!!! The Authentification Type determines how the data is encrypted. The manual says that the default value is "disabled", so change it immediately to WPA!!! (see page 20,21 of the manual).
    Otherwise people will be able to use your internet connection via WLAN!

    Note: The manual says that your router has "only" WPA and not WPA2. But if for some reason your router allows WPA2 encryption set it to WPA2.

    5) Use the MAC Address filter (see page 20,21 of the manual). Every ethernet device has a unique MAC address. Tell your router which MAC addresses are allowed, i.e. which computers/laptops are allowed to have access.

    Further reading:
    How to secure a wireless LAN (WLAN)
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