@SagnikNayak
Siti Broadband (Indinet) has CG-NAT. The static IP that you're talking about is basically a private IP provided by your LCO. Getting even a moderate NAT type is quite impossible.
I've used Siti in the past for almost 2 years and let me tell you something, they block all the ports by default. All the freaking ports. Using UPnP or even putting your machine in DMZ won't help you in any way, as you are behind several
routers, each of them having strict firewall rules blocking ports and all that.