Any Alternative of Port Forwarding??

Hi,

My ISP provided a really weird internet connection. i am accessing internet using a tv cable connected to a cable modem which is connected to my computer via ethernet cable..

He then set up network connection manually -setting my gateway, ipv4,subnet etc.. i have a fix IP .

The gateway that was provided is not of the device that i was given ,because when i open the gateway ip in browser it ask of for id & pass which is different from the device that i have..

SInce gateway ID is the router address - so its clear the network that i am accessing has its router to my ISP office..

THE THING IS-- I CAN NOT ACCESS MY ROUTER COZ I DONT OWN IT..

in this case is there any way to portforward?coz i want to test hacking in WAN.

can no-ip work in this scenario or it too requires a forwarded port????