Hide My MAC ADDRESS

[nanop1i]

Hi,
i am facing a great problem to hide my mac address. Well my problem in brief is, my isp authenticates me by my ip and mac address, now any person with a ipscanner can detect my ip and mac address. So by cloning my ip and mac address they are able to use my net connection. I am getting damn slow network speed.
Please help me out.
nb: I have tried a number of softwares viz:HIDEMYMAC,HIDEMYIP,ZONEALARM.. etc but still the ip scanner is able to trace my ip and mac.

Thanks in advance..

I am using sify broadband..

[PraKs]

Use this one

Made by an Indian.. FREEWARE

http://tmac.technitium.com/tmac/index.html

[nanop1i]

thanks i would out this product i hope it works out.. thanks once again