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I'm at my sister in law's place in Singapore. I'm not from Singapore but am here for a few months. She has some sort of cable modem made by motorolla (SB5101 Surfboard). I think it goes, through starhub or similar provider.

Anyhow, her PC is directly attached by cable (not wireless) and she can access the internet. There is no wireless router connected to it.

The PC is configured with DHCP and appears to be working. However, the moment I unplug her PC and plug in my laptop, it doesn't get an address. The interesting thing here is that I also see this toredo tunnel adaptor etc. I'm not familiar with what that is. It appears to be being assigned an IP v6 address and an IP v4 address.

I thought perhaps it's my laptop, but also when I plug in my DDWRT based router, it also fails to get a DHCP assigned address on the WAN port. I can't also seem to connect into any web configuration on the motorolla modem either.

Any ideas? what kind of setup is this? all I'd like to do is plug in my wireless router so I can roam around the house and also access the internet.

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up vote 1 down vote accepted

Typically when working with cable modems, at least the Moterola Surfboards I've worked with, you have to power cycle the modem any time you change the device that is connected directly to the modem. So, connect it to your laptop, reboot the modem and it will probably work!

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That was exactly it! thanks for that. – Matt H Feb 5 '11 at 7:20

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