as @pothi said
DSL speed is inversely proportional to the distance of your house from the exchange. => As the distance increases speed decreases.
Actually, it's very hard to get ~10Mbps over BSNL's copper cables if your home is more than a KM away from the exchange. For obtaining the described speeds, check the plan you're having is feasible through fiber. Ask your LCO and exchange to provide the same plan over Fiber.
Some other DSL plans are available over it