State-owned mobile network operator Bharat Sanchar Nigam Limited (BSNL) has announced plans to replace approximately 28,000 legacy 2G base stations with modern 3G/4G-compatible equipment, the Economic Times writes. According to BSNL Chairman Anupam Shrivastava, the rollout is expected to be completed by the end of March 2018, and the operator will begin offering 4G services in selected areas shortly afterwards. The official added that vendors Nokia and ZTE are in the lead for the project, submitting the lowest and second-lowest financial bids, respectively. The evaluation process is ongoing, however, and the equipment suppliers are expected to be finalised next month. The bidder with the lowest offer (L1) will be handed the contract for the West and South zones, Mr Shrivastava added, whilst the second-lowest bidder (L2) will be offered the North and East zones, if they agree to provide the equipment at L1 rates.