1) If you are using Firefox, you can use the Datafox add-on for Firefox web browser to keep yourself updated with your usage details.
After installing and configuring it, it will regularly update your usage from the Dataone portal automatically.
Here is the link to the Datafox add-on:
Datafox 2) You can use the just launched
Web Registration for Broadband Usage Alert facility by BSNL:
Web Registration for Usage Alerts
It is said to give you both E-mail updates and Mobiles updates (SMS).
3) You can also use any of the Bandwidth monitoring tools also to update yourself with your usage. But, it may be a little or more different from what Dataone records. But, it can give you a fair idea as to how much you
might have used.
ShaPlus Bandwidth Meter is a good bandwidth monitoring tool. You can download it here:
ShaPlus