I asked BSNL, they told that they are using EPON in my region. In Advanced Setting of my router, there is no EPON/XPON setting. I think the firmware is not universal.

@Chinnasamy Yes

I have bought TP-Link XC220 G3v V2 for FTTH Internet connection with BSNL (Maharashtra, India). After connecting the optical cable and starting the router, the GPON registration status shows GPON...