Gubru see if there's any firmware upgrades on your Linksys. Some devices may fail in UPnP mode or be unreliable. Particularly if it's an old or oldish model. But then, if it connects ok but suddenly cuts off it 'might' be ISP interference with special programs that block p2p programs as soon as they detect them. If you have a dial up option, see if you can connect with LW on that just to check to see if it works. (some isp's offer dial up also as a backup. I can connect via either if I choose. I simply need to change the net setting in my system.)

kamalis we need some more details: System details - help us to help you (click on link)

hi_shobhit76 yes as many details as you can obtain would be beneficial. Mumbai rings a bell in my mind that at least one ISP there blocks p2p (but I can't confirm that.)