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My "Dynamic" public IP Address will not change

Regular Visitor

My "Dynamic" public IP Address will not change

Hello everyone,

 

Over the past 10 days or so I have been off and on the phone with comcast support trying to change my public ip address. The obvious solution of opening command prompt and releasing/renewing does not change my public address. I have talked to dozens of people over the phone and been transferred all over the place and no one can figure out how to change my public ip address. At one point, a representative assured me that replacing my modem would change my public ip address and that did not work. Another person told me that since my public ip address is dynamic it will automatically change every week or so, which hasn't been the case either. The reason I cannot wait until my dynamic ip address changes is because an old friend of mine has managed to get my ip address from skype and ddoses me everytime I come online. I have purchased a vpn to protect myself from future attacks but I cannot find a way to change my current public ip address. It is getting extremely frustrating and I am on the verge of cancelling my service with comcast. Does anyone out there know how to change my public ip address? Thank you so much Smiley Happy

 

In case it matters, I use windows 7 and I do not have a router, I run an ethernet cord directly from my PC to my modem.

 

 

New Poster

Re: My "Dynamic" public IP Address will not change

 

 

Hello,

        You can't change it cause the Comcast Router has a Harwired Mac Address.  If the Router Mac can't be changed then comcast keeps issuing the same IP for the same Mac over and over again.  Since its the WAN Ip that is displayed everywhere you go, its the one you are wanting to change.  Sorry, but that will not change for as long as you are with Comcast, due to the Mac Address being hardwired for that specific modem.  I know with a lot of DSL providers, you can change your Routers Mac address, and then do the IP release and renewal.  Some of them if you power their routers down long enough will issue a new Mac and or WAN address.  Comcast could issue a new WAN Ip for that Routers Mac address, but good luck with that.  If you still want to keep giving a crack at it.  I suggest typing in "Change WAN IP on comcast" or type the model of your Router and add "change mac address" beside it in a Google search.  Maybe there is something new out that has been able to bypass it.  I doubt it though, it could be a little chaotic for Comcast to have their Routers changing Mac Address's.  Although I do think they should change the WAN IP for customer about every 4-6 months or so, mainly for security purposes.  Use to the only people wanting to change that IP were people causing trouble in different forums and etc, but now a days it helps keep your identity safe in about 50 different ways.  Hackers have got very smart about how to track people by their IP's, and so have certain malicious programs.  Anyways, hope my little throw in advice helped you figure your issue out.

Silver Problem Solver

Re: My "Dynamic" public IP Address will not change

The IP address is based on the MAC address of the device connected to it. You need to change the MAC address of your computer, in your case. That may or may not be possible, depending on the network hardware and drivers.

 

Either way, I would still STRONGLY suggest getting a router, even if you only have the one computer. Most routers include wireless, but you can disable it. If you are really paranoid, get one with removable antennas and remove them, too. Plus, most should allow you to override their MAC address if you want to change it. (NOTE: If you change the MAC address or device connected to the modem, you need to reboot the modem.)

 

The router adds an extra layer of security since the firewall will help protect your computer and other devices, even before any of it's own firewalls and other software load.

 

The IP is DHCP, but tends to be 'sticky'. Unless you are disconnected for a long time (probably at least a week, maybe longer), it will keep reassigning it to you. Changing the modem does nothing. I changed from an SB5120 to a 6120, and kept my address.

Silver Problem Solver

Re: My "Dynamic" public IP Address will not change


andyross wrote:
Changing the modem does nothing. I changed from an SB5120 to a 6120, and kept my address.

The exception being if you exchanged a straight cable modem for a gateway, which has an inbuilt router. Then the IP would change, I would think. (not sure)...

Diamond Problem Solver

Re: My "Dynamic" public IP Address will not change

 

FWIW, poster stated that they are not using a router. You have some other misconceptions / misinformation about the system as well..

Regular Visitor

Re: My "Dynamic" public IP Address will not change

So my only options are changing my MAC address which may not even be possible or cancelling my service entirely? How would purchasing a router cause my public ip address to change? I am not trying to get unbanned from a forum or website, I am trying to stop a hacker from ddosing me whenever I come online.

Diamond Problem Solver

Re: My "Dynamic" public IP Address will not change


Matt3989 wrote:

How would purchasing a router cause my public ip address to change?

 

Because the system will see a new / different MAC address on the LAN side of the modem being presented to it. This will force a change to your WAN (public) IP. Also, most routers have a built in MAC address cloning feature with which you will be able to clone different MAC addresses so that in the future you will be able to force further changes.

 

 


 

Regular Visitor

Re: My "Dynamic" public IP Address will not change

Ok, I just purchased a router. Is there anything in particular I need to during the install to change my ip address or simply plug it in and go?

Regular Visitor

Re: My "Dynamic" public IP Address will not change

It worked! Thank you so much everyone. You all have been more helpful and knowledgeable than any of the comcast employees I have encountered. Thanks again.

Diamond Problem Solver

Re: My "Dynamic" public IP Address will not change

Glad to hear !

Silver Problem Solver

Re: My "Dynamic" public IP Address will not change


Matt3989 wrote:

It worked! Thank you so much everyone. You all have been more helpful and knowledgeable than any of the comcast employees I have encountered. Thanks again.


If you look through the menus, there will probably one where you can change the MAC address. There may also be a CLONE button to quickly grab your computer's address. In the future, if you want to change your IP, just change one of the numbers (0-9, A-F), save it, then reboot the modem.

Diamond Problem Solver

Re: My "Dynamic" public IP Address will not change

Sort of an echo ? FWIW, I would recommend more so that you only use the MAC addys of equipment that you actually own.

New Poster

Re: My "Dynamic" public IP Address will not change

 


Paraniod wrote:

andyross wrote:
Changing the modem does nothing. I changed from an SB5120 to a 6120, and kept my address.

The exception being if you exchanged a straight cable modem for a gateway, which has an inbuilt router. Then the IP would change, I would think. (not sure)...


You hit the nail right on the head with that one.  I understood exactly what you were you were saying.   The same is vise versa.  Just switched from the gateway to the straight cable modem (Waiting for new Gateway to come in mail, so straight modem in the meantime) and it changed the IP immeidiately.  The gateway was disconnected for all of 30 minutes.  Of course in the City area's I have noticed that the IP changes rather quickly when switching from the Gateway to straight, or even just a swap out where the Mac changes will 99% of the time in the dense area's of the city change.  I am not for sure what the cause is in that, but from observation, that's the way it happens.  Good to hear the person got their IP changed with the new mac address.  Always nice when the community can pitch in to help each other out with these types of things. Smiley Happy

New Poster

Re: My "Dynamic" public IP Address will not change


EG wrote:

 

FWIW, poster stated that they are not using a router. You have some other misconceptions / misinformation about the system as well..


I worded it wrong in a few spots, was trying to throw the router in there as a reference.  Getting them the info that the Mac Address was the focus of the issue of the IP not changing more than anything was the idea. At least they got it solved, and in a timely fashion!  Smiley Happy