Recently Airtel announced that it will double the internet browsing speed for all its customers free of cost (i.e. if you have 256 kbps connection, it will automatically be converted to 512 kbps plan) and it seems like BSNL has followed Airtel’s strategy and has rolled a similar plan wherein broadband speed of all BSNL customers with any unlimited plan will be doubled without any extra charges.
As a proof, you can check out the speed test results of my 256 kbps unlimited plan on the image above. My home unlimited 256 kbps plan has automatically been upgraded to 512 kbps plan. Though, as per BSNL, this is just a promotional offer and will last until 26th April but, personally I am quite sure that this offer will be extended for an indefinite period considering the falling broadband tariffs of competing ISPs.
Besides this, BSNL also has several freebies for new dataone broadband customers such as waiver of activation charges, unlimited free data usage for first 15 days at a speed of 2 Mbps, etc.