Problem Cable modem IP add release/renew [Solved/Closed]

BadBoy10 1 Posts Friday August 22, 2008Registration date August 23, 2008 Last seen - Aug 23, 2008 at 11:57 AM - Latest reply:  eliytuangson
- Apr 7, 2012 at 10:01 PM
Hello,

I have finally been able to release and re-new my cable IP address after speaking with my cable provider. It was a real nightmare.

I have a linksys router WRT54G and connected with a cable modem. For the last 2.5 years, my IP adddress has not changed as my network is always on.

Anyway, I have decided to change my IP address.

First

my router was giving the IP 80.4.198.1XX and when I connected a laptop to the modem direcly I got the same IP 80.4.198.1XX .

Anyway, I did remove the coaxial cable from the cable modem, and turn off the modem.

2 hours later, reconnected the coaxial cable to the cable modem, then went to command promt (laptop connected directly to the cable modem, did ipconfig/release then ipconfig/renew.

to my surpise the IP address got release and was getting a new IP address 80.4.195.3X from my cable modem instead 80.4.198.1XX

I connected the modem back to the router and did a ping, and to my surprised thru the router I got the original IP 80.4.198.1XX. I can not understand why, I did a hard for the router, and reconfigure it, and still that IP address keep popping up, while the cable modem is 80.4.195.3X if I still connect the laptop to the modem.

Do I need to something in Vista to sort this problem? I want my router to give the new IP address of the cable modem?


any advice would be appreciated

cheers

BB
See more 

4 replies

+4
Helpful
I believe this has something to do with MAC address of the router, as the modem stores such information and makes a lease query based off that address (the modem itself most likely doesn't receive own external IP, yet in most cases accessible via web-interface - i.e. http://192.168.100.1 for Motorola models, google for your make. For this, I presume, you must be directly connected to the modem with one of your systems). One of the ways to resolve it would be spoofing router's MAC (if possible at all), another - reseting the cable modem to the factory default to clear MACs stored in modem's memory, which is easier to do via web-interface, but I wouldn't recommend it without notifying and hence receiving a blessing from your ISP first, as I'm not a professional and have only a vague understanding of the consequences, moreover never tried it before myself. As for what can you do to make the IP release/renewal easier next time - as far as I understand there is nothing to be done on the user side except what was already mentioned: reseting to factory defaults or spoofing router's MAC, which is probably not that easy to do, if that option is not openly available on your model.
Was this answer helpful?  
tech guy wrt54gs owner - Apr 9, 2009 at 04:23 AM
+2
Helpful
1
install the ddwrt firmware on your router iw will solve your problems .http://www.dd-wrt.com/dd-wrtv3/
Thank you for posting this article in this forum I will bookmark this page and tell my friends about this ...