IoT Gateway

We are developping a communication gateway (or Border Router) between Internet and one or more wireless sensors networks. It allows the monitoring of each network from a single web interface. The same interface is also used to create new sensors networks and to gather data that are sent from our sensors (temperature, humidity…).

We use hardware on he shelf which are able to work well in the legacy environment of the ENSP (Ecole Nationale Supérieure Polytechnique) of Yaounde, where we made our deployment tested.

 We extend an existing research software from the CETIC laboratory to develop our IoT framework. Below is a first simple test of a wireless sensor network made of five nodes, connected to the raspberry based gateway through a supplementary node that relays wireless communication (BR node).

The figure shows the graphical web interface we used to monitor and manage the network. Arrows show the IPv6 routing plane that sensors have established with the RPL routing protocol. The number “10” is the unique identifier of this network. Our first step of extension is to allow a single gateway to manage several wireless sensors networks

In the second test, we added three nodes (Z1 and Re-Mote from Zolertia) around the first network. Our management interface was able to separately manage each network, as one can see the second sensors graph with the network identifier set to “20” on the web interface.

 

We can now deploy several gateways that will manage several networks. We are working on the synchronization of these gateways to provide a global view of each network wherever they are deployed. A linear programming approach will be used to optimize two opposite constraints. The first is that sensor networks will use the maximum number of gateways and the second is that each gateway should accept a maximum number of networks, but gateways have not infinite resource. The trade of is between sensor network needs of gateways to ensure a good Internet connection and the limited number of gateways.