The Internet of Things

Explain what the Internet of Things (IoT) is and name three connected objects you know, stating what data or "sense" each one provides.

What does any given object, such as a lamp, need to become a connected object? Mention at least three elements and explain the role of each.

The figure shows how various household appliances are controlled from a smartphone, with one element in the chain marked with ?. Identify this element and explain the path followed by the command "turn on the light" from when you tap the screen until the light bulb turns on.

Explain the role played by a Wi-Fi router in a connected home and what happens to smart appliances in the house when the router is turned off or loses internet connection.

Differentiate between Bluetooth and Wi-Fi as ways to connect a device: range, power consumption, and a typical device example for each.

Compare an infrared remote control with controlling a device over the internet: range, network requirement and privacy. Give an example where each option is clearly preferable.

Explain what "the cloud" means in the context of the Internet of Things: where data is actually stored and what happens to devices if the manufacturer closes the service (real-world cases of devices becoming useless or "dumb").

Compare a device operating locally (all logic contained within the home) with one depending on "the cloud": response latency, privacy, and manufacturer reliance, giving an example of each type.

Design an IoT system that alerts a family on their smartphone if the moisture level of a houseplant drops too low: what sensor you would use, how it would connect, how the notification would arrive, and how the system would behave when there is no internet connection.

Explain what characterises a strong password and why leaving "123456" on an IP camera is a serious security issue.

A fitness tracker records your steps and sleep. Reason what sensors it uses, where this data is stored, and which app displays it. What risk to your privacy do you see in this operation?

The owner of a tourist rental property installs a smart lock connected via Wi-Fi to the router and claims: "I'm not worried about security: the lock has a 16-character random password, so no one from the street can breach it". a) Refute their statement by identifying and justifying two real attack vectors against the lock that do not rely on guessing that password (for example, vulnerabilities in the manufacturer's firmware/cloud or attacks on the local Wi-Fi network). b) Design an improvement in the network and authentication architecture that increases the security of remote access without relying solely on the device's password.

Devise a useful smart home rule and another that is a bad idea, both of the form "if [condition], then [action]". Justify each one considering false positives and what happens when the rule fails.

A school replaces 60 traditional light bulbs with low-cost "smart" bulbs (5,0 W of LED lighting and 1,5 W of continuous standby power consumption due to the Wi-Fi connection). Three years later, the manufacturer goes bankrupt, shuts down its cloud servers, and the mobile app stops working, preventing them from being turned on or dimmed remotely. a) Calculate the total energy (in kWh) consumed in standby by the 60 bulbs over those 3 years (1095 days) and compare it with the actual lighting consumption if they are turned on 5 hours a day for 180 school days per year. Interpret the result from the perspective of energy savings. b) Explain the "bricking" phenomenon these bulbs suffered and what technical design alternative (local open protocols versus cloud dependency) would have ensured they continued to work after the manufacturer closed down.

A manufacturer of smart bathroom scales offers two versions of the same product: Model A costs €15,00 and requires creating a free account in its cloud mobile app to record weight, body fat, and heart rates; Model B costs €55,00 and stores data solely in the internal memory and on the user's local network (without external servers or subscriptions). a) Explain the hidden business model behind Model A: how the manufacturer monetizes the price difference at the expense of the user's biometric data, and what risks of commercial profiling or sharing with third parties (such as insurance companies) this entails. b) Technically justify why Model B is more resistant to planned obsolescence and guarantees the user's long-term digital sovereignty, despite its higher initial cost.