Networks and Protocols (NP1 + NP2) Final Programming Project

As a last exercise for the two subjects (NP1 and NP2) you will work in teams of 2 people on a project that shows what you have learned from these topics. You will develop (program) a system to monitor the amount of people in a room, by detecting their smartphones, uploading the data to an external server for analysis and visualization. In the following sections we describe what should be covered for the two subjects.

Requirements for NP1

Your system should manage a sensor network, formed by your ESP32 nodes. We assume that you could have at least one node per room and that each room has a WiFi access point reachable. In this context:

• Your nodes should be able to connect to the AP using WiFi, with WPA2-PSK security.

• Your nodes should provide a provissioning option, so that you can configure the wifi SSID to connect to. You can use a softAP or a BLE provisioning method, that is up to you.

• Your nodes should use BLE to compute the number of other BLE devices in its range (an estimation of the number of people in its range), using the RSSI to compute the distance to the node (the student should research for methods to compute the distance).

  • Alternatively the student can opt for using a different technology of his choice to estimate the number of people in the room.

• The node should be configured through the menuconfig system, to establish its parameters:

  • Sampling period.
  • Server where the samples should be sent to (see requirements for NP2).
  • Range of valid distances.
  • etc.

Optional Parts for NP1

Optionally you can extend the project incorporating some extra features like the following (these are only ideas, you can also propose some others):

• Consider an scenario with larger rooms, in which one node is not enough and the wifi AP is not reachable on all points. In this scenario you can use the ESP's wifi-mesh technology to build a mesh of nodes in the room.

• Study the Over The Air (OTA) features of ESP and prepare your nodes to receive OTA updates from an external server. Together with NP2 you can consider to configure the nodes to trigger the OTA update through MQTT (or any other application protocol you are using).

• Add a GATT server that allows the node parameters to be configured with a BLE client.

Requirements for NP2

The developed system will periodically publish the calculated data for the population of BLE devices in the room, sending it to an external server for further storage and analysis.

Specifically, the minimum requirements related with NP2 include:

• You will select an application-level protocol among those studied in NP2 (or, alternatively, other similar protocols of your interest) and use it for data publishing.

• Servers/brokers to which data will be sent will be configured via menuconfig, together with the sending period and any other configurable parameter considered useful.

• You will select and use one of the two data representation methods studied in the course (JSON or CBOR).

• Data will be gathered by Node-RED and submitted to two different destinations:

  • A dashboard of your election (e.g. Node-RED, Grafana, ...).
  • A database (e.g. MongoDB), where it will be stored together with a timestamp.

Optional Parts for NP2

Optionally you can extend the project incorporating some extra features like the following (these are only ideas, you can also propose some others):

• Use encryption at all levels of the communication (e.g. MQTT).

• Develop an alarm system that triggers under certain conditions (e.g. when the amount of BLE devices is out of a pre-established range), and sends a notification to the user using external services (e.g. SMS, e-mail, Telegram, ...).

• Implement bi-directional communication, with the possibility of externally modifying the behavior of the ESP32 (e.g. modifying sampling or sending period).