Here are three prepaid recharge plans of BSNL:

BSNL's Rs. 186 prepaid recharge plan
This prepaid recharge plan of BSNL offers unlimited data with internet speed reduced to 40 Kbps after the usage of 1GB. It also gives unlimited local and STD voice on- and off-net calls in home LSA (licensee service area). On-net calls refer to BSNL to BSNL subscribers while off-not calls mean BSNL to other networks. LSA refers to a service provider's circle. This prepaid recharge plan of BSNL is valid for 180 days.
BSNL's Rs. 187 prepaid recharge plan
This prepaid recharge plan of BSNL offers unlimited data with internet speed reduced to 40 Kbps after the usage of 1GB. This prepaid plan offers unlimited local and STD on-and off-net calls in home LSA and national roaming excluding in Mumbai and Delhi. This prepaid recharge plan of BSNL is valid for 28 days.
BSNL's Rs. 485 prepaid recharge plan
This prepaid recharge plan of BSNL offers unlimited data with internet speed reduced to 40 Kbps after the usage of 1GB data per day for 84 days. The plan, however, is valid for 84 days. This prepaid plan offers unlimited local and STD on-and off-net calls in home LSA and national roaming excluding in Mumbai and Delhi.
The effective date of implementation may vary from circle to circle. "Thus the same may be confirmed from respective circle offices", BSNL mentioned. "PV (plan voucher) 186/485 will be available for J&K, Assam and NE-I/II also but with 90 days PV validity only," BSNL said.