How to block social websites on BSNL broadband vmc an1020-21 ?

I have an modem that is BSNL broadband and on opening bsnl admin page there is no advanced option for url blocking.

Plz help me for how to block facebook on my bsnl broadband?

If you have already looked in all the router settings, then check in your antivirus settings. You can also block any site you want in firefox by installing just an addon. There are many addons available that can also block certain websites.

Thanks for the reply . Yes there is an security system in my antivirus that is parental lock and its working but i want to block the url from my modem so that no one able to access the specified url as from wifi

You can do that by using a router that has an option to block urls or ip addresses. I think most of them have this option but be sure to check before you spend your money.