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I'm having a problem, sometime I'm getting ddosed for no reason (I verified with commview,wireshark). The first time I noticed I didn't think it was a problem because I was pretty sure my ip was dynamic (it was) but after resetting my router thousands of times my ip stays the same (had the same for more than 2 months).

It has become annoying so I called my isp and told them the deal and they assured me it was dynamic so I resetted my router 3 times to be sure and it didn't change. So I called back and told another guy what has been happening and said the same thing, blablabla your ip is dynamic, societies buy static ips but I kept saying I got the same ip for months. So he called another tech from the company which owns my ISP and they told him that resetting the modem won't guarantee an ip change because my modem takes the first one available and I should try turning off the internet for 24h to maximize the chance of having a new IP but there is no guaranteed that it will work. I asked him to talk to the tech (so I can tell him to assign me a new ip manually) but he was told it's not allowed.

Does that make sense? Is there a way to force my modem to take another ip?

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up vote 6 down vote accepted

No, the reason you are getting that address deals with the ISPs DHCP server. it records your MAC address, and attempts to always provide you the same IP if it can. since its their server doing it (and you cannot change your MAC or they will not provide service to your modem), there is nothing you can do on the client end. Sorry.

edit: BTW, the reason they suggested 24 hours, is that is likely the lease time of your DHCP address. one of the items required to get it to consider giving you a differant address is the expiry of your existing one, but it is likely that the server will give you the same one over and over again, even with an expired lease, unless the assignment pool for your segment is largely in use.

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Exactly, and the longer the modem is unplugged the more likely it is that a) your DHCP lease expires and another device receives the IP. – AthomSfere Jun 14 '13 at 20:54
im done with this isp. already called another company – Sdki7 Jun 14 '13 at 21:54

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