This is not a problem. Everyone who connects to the internet with dial-up has a different IP number each time they connect.
Google recognizes you by the cookies they leave on your computer.

even for high speed it changes frequently, not an issue

No issue my ADSL connection also changes IP everytime I turn on router. No big deal.

Really.................. :D
Then it should not be problem with Adsense account signup and account login.

But i got another prob? The ip is shared not static ;S

Almost all home connections ips are dynamic. Static IPs are only given on demand or to business internet connections such as T1.

right... but himalay... how does google recognize the nasty clicks by adsense accountholders itselves? Off course, IP comes into play that time. So, if the IPs are dynamic, others may click intentionally to ban your adsense account (its totally noob sense :S).

well, it seems no one like my thread... is it too dumb question?

Google has a number of ways to identify click fraud, not just one. IP number is only one part of the equation, and nobody knows the equation except for Google. If you are careful not to click on your own ads, you will probably be okay. But if you are that worried about it, then it's probably not a good solution for you.

thank u

As a beginner you should less concern yourself with such technicalities and just focus on making a great site and following Google's guidelines.

As I understand it, the IP address remains the same within a session. So if someone was to be repeatedly clicking without disconnecting from the internet and re-connecting then the clicks would all come the same IP address. If you really wanted to disconnect and reconnect again for every click (to get different IP addresses) then either you would need to have designed a clever little program to do it automatically for yourself, or, doing it manually would be .... boring, tedious and not very remunerative.