Need Help in resetting BSNL Wifi Type II modem

Hi Friends,I have a Type II wifi modem "Ustarcom" BSNL Data One BroadbandNow the issue is I had given to my friend for few days I don't know what he has done..I tried calling him and getting info about the details of login to router admin "192.168.1.1" but failedand also I'm not able to access my wifi network password I don't know what he has given the name...Can, You guys help me to reset my router any other way than login into admin.I tried looking a holl on equipment to pin reset but failed.But still not able to understand how to reset the modem to default. Later I can use my user name and password which I remember, which has no issues.Thanks In Advance...