nectivity.
Towards rural connectivity: Gram Marg
The Gram Marg rural broadband project  at the Department of Electrical Engineering, Indian Institute of Technology Bombay (IIT Bombay), aims at connecting the unconnected by overcoming the barriers and challenges to connect rural India. In order to provide ubiquitous connectivity to rural, remote areas, research and development at the Gram Marg lab has suggested that a shift is required from traditional technologies to a more affordable, efficient and robust technology. To this effect, Gram Marg has deployed two large-scale test beds since its inception in 2012.
The first test bed that was set up by Gram Marg was based solely on TV white space (TVWS) technology, covering seven villages in Palghar, spanning an area of 25 sq km, in 2013-2014. The purpose of setting up a TV UHF band test bed was to check the feasibility of using TV UHF for middle-mile connectivity to provide high-speed broadband access to the villages. The test bed consisted of a single base station which connected to 12 clients situated at selected locations at varying distances. A 20 Mbps leased line was provisioned at the base station. A total of 10 Wi-Fi access points were deployed as well as three community kiosks, which were backhauled using the TV UHF band. Detailed results from this test bed have been published in papers. 
The second test bed is a scaled-up version of the earlier test bed which experimented with the feasibility of unlicensed bands such as 5.8 GHz for middle-mile connectivity covering 25 villages in Palghar, Maharashtra. The test bed spans an area of about 300 sq km, a network diagram of which is shown in Figure 1. Villages are divided into clusters of four to five villages, resulting in six clusters. Each cluster has one base station that has a fibre point of presence. In one cluster group of 15 villages, access is offered at Gram Panchayat offices only. In a second cluster group of 10 villages, Wi-Fi access points are deployed at strategic locations that can be accessed in and around those locations. In all, a total of 60 Wi-Fi access points have been deployed in the 10 villages, with six access points per village. These access points are set up at the Gram Panchayat office, primary health care centres, at least one school and one community centre. A total of 106 Mbps bandwidth has been procured to serve the 25 villages.
Figure 1. Network diagram of 25 villages in the Palghar project
Establishing a community-led network
Seeding the growth of a community-led network has been an important achievement of the test bed. An internet needs assessment survey suggested that enabling connectivity was not enough for the villages. There needs to be ownership of the network by the village authorities so that local and regional needs will be prioritised. Community involvement in the connectivity can help in the maintenance of the network and take care of the security of the devices. Local youth from the village community can also be effectively engaged through skills development and training.
Out of the 25 villages covered in the second test bed, community networks were set up in 10 villages only. They were selected for two reasons: i) the location of these villages was in remote pockets and hilly areas, and ii) there was no mobile coverage in these villages. Figure 2 depicts the network diagram of the 10 villages where the community network is currently operational. As seen in the figure, a point-to-point 5.8 GHz link has been set up from the tower at the base station to the Gram Panchayat office. Connectivity is further distributed inside the village in a mesh network through six access points that are placed strategically inside the village. As a result, the entire expanse of the village is Wi-Fi enabled.
Figure 2. Community network villages in Palghar
The network in the 10 villages is maintained through community participation. A village youth is nominated as the Village Level Entrepreneur (VLE) who undergoes training and skill development to maintain and operate the network in the village. Th