From a user's side, is there any way to force a cable modem to
obtain a new IP address? I tried turning it off then on and still
got the same IP address.

"John Smith" <jsmith@company.com> wrote in message
news:e4Fad.56283$ci3.3359588@twister.southeast.rr. com...
You turned it back on too quickly. When the IP is released, it is free for
someone else to use. If nobody else turns their cable modem on, no IP is
needed. You turn yours on and it needs one. It gets one that is still not
in use. It might be tough to get a new IP without leaving the modem off for
a few days, as it's likely most cable modem users leave the modem on
4/7. -Dave

On Mon, 11 Oct 2004 23:55:54 GMT, John Smith wrote:
Why?

Yep, looking at my lease, it will expire after about 5 days.

Hard to believe anyone else would have had left theirs off for 5 days
so they would get my ip address instead when they boot up durine my
expired time.

Maybe a new customer on my network segment could come online after my lease
expired and get it.

Of course that would assume the ip address it not tied to the nic's
mac address so the ISP can hunt you down when required.

Buying a new nic or have your nic give a false mac might change it.

"John Smith" <jsmith@company.com> wrote in message
news:e4Fad.56283$ci3.3359588@twister.southeast.rr. com...
If you are behind a router simply spoof the MAC address of the router and
then do a DHCP release/renew on thr router. That should work. If not that
then swap out you NIC in your computer and do a DHCP release/renew with the
new NIC and it should work then too. Other than that shut all off for a
time period of ??????? and then turn it all back on.

On Mon, 11 Oct 2004 23:55:54 GMT, John Smith <jsmith@company.com>
wrote:

Why? Have you been a bad boy?????

;-)

John Smith wrote:
First, a clarification. Do you want the modem to get a new IP address,
or the device (computer, router, etc.) connected to the modem to get a
new IP address?

If you want the device attached to it to get a new IP address, you may
need to see when the lease expires, and take the device off the network
*at least* until that time. The theory is that once it is no longer
leased, someone else could take it. However, if your node has a pool
with plenty of IP addresses, that may not happen. And if another device
hasn't taken the available IP address, you'll get it back no matter how
long it's been.

If you have a router, you can probably spoof a different MAC address.
That will likely get you a new IP address. However (and isn't there
always a "however"?), it would be unwise to just randomly come up with a
new MAC address. This could potentially result in problems that could
affect the network. In a case like that, getting you off the network
will be the remedy the ISP takes. Only spoof MAC addresses of NIC cards
in your possession.

If you're not using a router, the easiest way is to install a new NIC,
or buy a router. (Of course don't spoof the IP address of the NIC you're
putting behind the router!)

That's how to get a new IP address for the device connected to the
cablemodem. But if you want the modem itself to get a new IP address,
you're probably out of luck. While the modem gets it's IP address by
DHCP, the customer account software used by most big cable Internet
providers will keep the modem IP address and the account linked. That
is, even if you went out and bought your own modem, once the modem is
identified as being on your account, it will be given back the same IP
address you had before. If there is a chance to change your cablemodem's
IP address, it would be to get a new modem. But don't count on it.

Of course this all begs the question of why you would want a new IP
address? What problem do you think this will solve?

--
Warren H.

==========
Disclaimer: My views reflect those of myself, and not my
employer, my friends, nor (as she often tells me) my wife.
Any resemblance to the views of anybody living or dead is
coincidental. No animals were hurt in the writing of this
response -- unless you count my dog who desperately wants
to go outside now.
Blatant Plug: Fahrenheit 9/11 ships 10/5. Order your copy now:
http://www.holzemville.com/mall/911.html

John Smith wrote:

You have to turn if until the lease expires and hope someone else grabs your
current address.

--

(This space intentionally left blank)

Warren wrote:

Some news servers post user's IP address. I'm not really
comfortable with that. That's why I want to know whether it's
possible to change the IP address.

On Fri, 15 Oct 2004 02:08:40 GMT, John Smith wrote:
Good firewall should keep anyone knowing your ip out of your box.
Have it drop packets and they won't even affect your upstream rate.
You are using a safer browser, Mozilla Thunderbird 0.8.

I have been on @home, attbi and comcast and always had my ip address in
my posts. No problem so far. Quick google search shows
Results 1 - 10 of about 12,600 English messages for author:bit
author:twister. (0.40 seconds)

John Smith wrote:
So you would want to change your IP address after every time you post?

And what does it matter that people know your IP address? (Unless you're
with an ISP that has nothing in place to screen out DoS attacks, which
would be unusual.) And, of course, you're using some kind of a firewall,
aren't you?

Trust me when I say that it doesn't matter if people know your IP
address. As some others around here can tell you, I've pissed-off plenty
of people, and I haven't had any problems. (Of course if someone wants
to prove me wrong, I'm sure they can find a way. But your typical psycho
script kiddie isn't that bright.)

But if it really bothers you, post through an anonymous reposter. (Of
course someone saying things that piss people off from behind anonymous
reposters often don't have much credibility once someone calls them on
it.)

--
Warren H.

==========
Disclaimer: My views reflect those of myself, and not my
employer, my friends, nor (as she often tells me) my wife.
Any resemblance to the views of anybody living or dead is
coincidental. No animals were hurt in the writing of this
response -- unless you count my dog who desperately wants
to go outside now.
Blatant Plug: Black & Decker Landscaping Tools & Parts:
http://www.holzemville.com/mall/blackanddecker

Using a motorola surfboard 5100 all I need to do is to change the
mac-address of my router, and turn off the surfboard for 5 secs...
Sending an email to myself and checking the internet header I see my IP
effectively changed afterwards

success


"John Smith" <jsmith@company.com> wrote in message
news:e4Fad.56283$ci3.3359588@twister.southeast.rr. com...
From a user's side, is there any way to force a cable modem to
obtain a new IP address? I tried turning it off then on and still
got the same IP address.