I Am Using BSNL Internet Broadband (Landline ADSL). I Have TP-LINK TD-W8951ND 150Mbps Wireless N ADSL2 Modem Router. And This Router Works Great, I Have No Problem At All. But I Am Not Satisfied With BSNL, That's Why I Am Changing BSNL Internet Broadband To GTPL Internet Broadband (Fibre Optic). So My Question Is Can My TP-LINK TD-W8951ND 150Mbps Wireless N ADSL2 Modem Router Will Work With Fibre Optic Of GTPL Internet Broadband??? Or I Have To Buy Another WIFI Router Which Comfortable With Fiber Optic Of GTPL Internet Broadband??
An ADSL modem/router will not work with a non-ADSL system, be it cable or fiber. Just like a cable modem will not work with ADSL, or a fiber modem cannot connect to cable broadband.
After the Modem.....all routers should work. The different modems do the translation from whatever system they use (cable/ADSL/fiber) to regular ethernet.
But no, you cannot use your existing modem/router combination with another system.