BSNL has invited bids from both independent telecom tower firms and the tower subsidiaries of Bharti Airtel and RCL for providing infrastructure in over 500 locations across the country for a period of 15 years (extendable by five years on mutual agreement). BSNL is planning to invest Rs 600 billion over the next three years to expand its GSM, broadband and WLL services. The company is targeting a market share of at least 33 per cent by 2010.