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Dehumidifier

|< < Prev #3109 (June 30, 2025)

Title text: It's important for devices to have internet connectivity so the manufacturer can patch remote exploits.

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Explanation

In this comic, Randall mocks the recent trend of various appliances, such as stoves and juicers, being connected to the internet even though one would expect them to be able to function without an internet connection. A dehumidifier removes moisture from the air. There are no obvious ways to improve dehumidifier operation without changes to its hardware, so it's unclear what benefit being able to receive updates via the internet would confer. Cueball's sarcastic reply underlines the unlikeliness of a situation occurring where an update would be necessary. The implication is that many of these internet-connected devices are examples of over-engineering a solution to do things 'because we can' or because it makes it sound advanced and therefore more desirable to the customer, rather than because it offers any real added value.

Dehumidifiers can provide information which would be useful to access remotely. For instance, it might be helpful to know the level of water in the storage tank (which must be emptied when full), the percent of time the humidifier is paused for de-icing, a log of the humidity level over time, and whether the humidity exceeds a certain limit (which could indicate dehumidifier malfunction, or that the dehumidifier is inadequate to the conditions). A local wireless network connected via WiFi is a reasonable way to send this information to a user or to other local devices.

However, many devices like this now offer, or even require, connections to a special app or to the internet. They typically connect to servers run by the device's manufacturer. When that server goes away, the devices may stop working.

The title text says that authorized internet access is required to patch remote exploits (i.e., harmful unauthorized access from the internet). If this is the only use case that requires internet access, it would be much simpler to remove the attack vector for remote exploits by not having it connected to the internet in the first place. The most likely source of remote access would probably be the remote updater itself. However, there is proof-of-concept of devices being hacked through acoustic-based or light-based attacks (possibly through hacked speakers or even from outside the house), and a patch could possibly circumvent those attacks.

A related device was previously referred to in 3044: Humidifier Review, and the issue of possibly considering online protection of devices that (arguably) should not be so easily exploitable was looked at in 463: Voting Machines and 1966: Smart Home Security. Comic 1912: Thermostat also deals with risks of adding computers to appliances.

Transcript

[A store salesman, Hairy, is showing Cueball a dehumidifier with a "SALE" label on it. Several other unidentified devices, possibly other dehumidifier models, are shown in the store as well.]

Hairy: This dehumidifier model features built-in WiFi for remote updates.

Cueball: Great! That will be really useful if they discover a new kind of water.

Trivia

Technically there are many different kinds of liquid water, based on the possible isotopes of hydrogen and oxygen atoms that its molecules are composed of. One of the most well known is heavy water, deuterium oxide, that is sometimes used in nuclear devices. There are 3 naturally-occurring isotopes of hydrogen, with 6 possible combinations for its two atoms in a water molecule, and 4 naturally-occurring isotopes of oxygen. This gives 6 × 4 = 24 kinds of naturally-occurring water molecules, which could be present in liquid water in any proportions, although 99.7% of all such molecules will be the 'normal' version of water. (The isotopic ratios in "natural" water are relatively stable, so there's very little variation in water found in nature.) There are also synthetic isotopes of each, all radioactive, most having short half-lives. How many of these could be used to constitute water would depend in part on one's definition of whether a molecule of water could be said to have been formed prior to the decay of its constituent atoms. Each isotopically-distinct version of water has very slightly different physical and chemical properties, though the differences are small and the versions hard to separate. (Separation is further complicated by the extremely rapid rate with which molecules in liquid water exchange hydrogen ions (protons) between themselves.) The differences would not be at all important to a consumer-grade dehumidifier.^{[citation needed]}

As of when this comic was posted, there are also 26 known phases of ice (solid water), each of which could be made from any combination of the isotopically-distinct versions of water in any proportions. These might count as different "kinds of water", and one was discovered in 2025; others may yet be discovered. Only one of these phases, Ice I_h, is likely to be found on an iced-over dehumidifier under normal conditions of use.

In the Twin Earth thought experiment, there exists a second Earth (called Twin Earth), in every way identical to ours, except that there is no water as we know it. Instead, there is XYZ, a substance that is chemically distinct from water, but is experientially identical to water, and referred to by the inhabitants of Twin Earth as "water". Surprisingly, this dehumidifier might be useful, if the manufacturer was also planning to sell it on Twin Earth.

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