## Module 6: Living on a decentralized network 1. Recap 2. Motivation: Smart Environments and IoT 3. Technologies of Smart Environments 4. LoRa Workshop --- # Recap * Learned about mesh concepts * Built WiFi mesh nodes * Used IPFS to store and share files * Talked about how to plan networks for a community * Used tools to measure and evaluate network quality --- # Today * Apply our knowledge of WiFi networks to other types of wireless devices * Talk about the .highlight[Internet of Things] and .highlight[Smart Environments] * Build a .highlight[LoRa node] through which we can send and receive packets over radio --- # Motivation * When we think of the internet communication, we’re often thinking of our experience with the World Wide Web * However, most new connected devices are *embedded systems* with wireless capabilities * An IEEE report estimates *30 billion devices* will be connected to the internet by 2020 --- # Smart environments * **Internet of Things**: Internet connected devices are becoming part of our daily lives for automation and sensing * In some cities they are becoming a part of city infrastructure, some people call these ideas *Smart Cities* --- # Need for network literacy Although these technologies can be immensely useful for sensing and automation there are concerns about: ## Security IoT device manufacturers have followed notoriously bad security hygiene. The 2016 Mirai Botnet DDoS attack exploited thousands of vulnerable internet connected CCTV cameras to take down DNS servers ## Surveillance Ubiquitous sensing in our environments raises concern about who has access to sensed data and what they may do with it ## Resilience As we become dependent on internet connected devices we need to ensure we have access to alternatives during failure --- class: center, middle # How do smart environments work? --- **How do smart environments work?** ## Devices * **Sensors** for collecting data from the environment * **Transceivers** for sending and receiving wireless information * **Microcontrollers** are the brains of the device --- **How do smart environments work?** ## Gateways Connect the device to the rest of the internet --- **How do smart environments work?** ## Servers Servers operated by your device provider or other third-parties manage your smart device's data  --- # Wireless technologies Smart devices today can use many different wireless technologies  --- # Choice of technologies depends on... * Cost * Range * Power Requirements * Data Rate * Licensing * Coverage * Ease of Installation --- # Why LoRa is a promising choice * **Cost**: Low Cost; $2 RF transceivers * **Range**: Long Range; Advertised up to 25 km; World record: 702 km * **Power Requirements**: Very Low Power; Sensor applications ~10 Year life from 2 AA batteries * **Data Rate**: Low Data Rate; ~150 bps * **Licensing** (900 MHz in Canada): ISM Band; No license requirement! * **Coverage**: No LoRa providers; need set up our own gateways * **Ease of Installation**: Community is developing and supported hardware is becoming available --- class: center, middle # LoRa workshop --- # LoRa decoded LoRa can achieve such great distances with such low power because it is not very susceptible to noise. LoRa works remarkably well with low signal strength. LoRa uses *Chirp Spread Spectrum Modulation*, ie. the information is encoded in the shifts of increasing or decreasing frequency.  .footnote[Image source: https://revspace.nl/images/d/d2/DecodingLora_Project.jpg] --- # Steamlink We're using an open source community platform for building, deploying, and managing low-cost low-powered long-range networks.  --- # Build a node! Let's build a circuit to connect to the network. You can send a message by pressing the button. Received messages should light up the LED.  In your browser, open `steamlink.local` to see your node!