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I have a very strange problem regarding the office network. We are currenltly in a executive suite and when i connect to wan via ethernet cable i get dhcp assigned IP address in my network config. I hooked up the linksys router to the wall expecting it to receive all the necessary ip info but that didnt work. So we have been assigned static ip address to put in to our router later but even with the static ip router doesnt seem to connect to internet. But using the same ip address and assigning to laptop works. I m very puzzled what might be the cause of this so any help is really appreciated.

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up vote 2 down vote accepted

Does your ISP assign the DHCP address based off your computer's MAC address? If so, generally the Linksys routers will allow you to "spoof" the computer's MAC address on it's external interface. This would allow your router to pull all of the relevant IP info dynamically.

Just a guess.

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We havent given them any mac address or registered it with the isp also i tried connecting with a different laptop it works also just not with the router. – user16877 Mar 1 '10 at 21:31

I'm assuming you want each machine connected to have it's own ip address assigned by DHCP? Have you tried hooking up a switche rather than a router?

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As mentioned by @ge0ff73 it's quite possibly the MAC address of the router not being accepted by the ISP. The MAC address is transmitted to the DHCP server anytime you request an IP, so even though you haven't told them the MAC, it's still in their system. All MAC addresses reveal the make/model of the system and card that's connecting. A lot of broadband ISPs have started denying connectivity from router MAC addresses and only allowing connectivity to valid PC MAC addresses. In your router config, there should be an option to clone the MAC of your PC. Do that using the last PC you connected and have confirmed internet access with and then check to see if your router can connect or not.

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