3109: Dehumidifier
| Dehumidifier |
 Title text: It's important for devices to have internet connectivity so the manufacturer can patch remote exploits. |
Explanation[edit]
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This is one of 87 incomplete explanations: Needs to be cleaned up (grammar, etc.). Remove this notice once done. If you can fix this issue, edit the page! |
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. Modern machines are incapable of self-modifying their hardware "on the fly". They require physical intervention to modify, by a person, and any associated firmware updates can be accomodated for through the tools the suitably-equipped engineer may use. Practical entirely self-modifying machines could, perhaps, be composed of practical self-organising nanobot elements. Thus it's unclear what benefits there are in being able to receive updates via the internet, in any classically constructed machine, and 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 might be useful to access remotely. For instance, it might be important to know the level of water in the storage tank (which must be emptied when full), the percentage of time the humidifier is paused for de-icing, a log of the observed 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). Though how actionable and urgent this information would be is debatable, and periodic checks of an on-device status panel should suffice for most practical situations.
However, many devices like this now offer, or even require, connections to a special app or to the internet, under the remit of sending operational information to a user through their own devices for record-keeping purposes, or attempting to alert them to a particularly critical condition (or at least the temporary failure of any networking). They are typically configured to connect through servers run by the device's manufacturer, perhaps to provide them with real-time telemetry and (potential) adjustment of all their licensed equipment. But when that server goes away, some 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 sole use-case that requires internet access, it would have been much simpler to never have had the attack vector for remote exploits connected in the first place. The most likely source of remote access would probably be the remote updater itself. (There are proofs-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, but this already opens up the possibility of the secondary unsecured attack-vector being used to hide the exploit, or even close down the ability to pick up any official fixes by the 'normal' network-based method.)
"New kind of water" could refer to heavy water, tritiated water, doubly labeled water, hydronium, semiheavy water, deuterium-depleted water or something which isn't detected/invented yet. However, generic dehumidifiers are not generally required to distinguish between these and treat them differently so, unless its hardware is already heavily modified for a particularly novel environment, the effectiveness of remotely adding differently preferential behaviours is questionable. It is also very hard to imagine a situation, in which vapors of "new kind of water" would end up in house in significant quantities; the various "new waters" can cause minor biological harm (being too weak to use as chemical weapons, yet too unsafe to be found in significant quantities in an ordinary house). They are most predominantly found in nuclear reactor facilities, which in turn have no everyday use for household dehumidifiers, and don't appear naturally to any significant degree, if at all.
Yet there is a method, which could allow to get positive results from built-in computer and Wi-Fi: gaining unrestricted access to device's internal computer (anything capable of running Doom and/or participating in "Mirai" botnet does have a computer inside), possibly via undocumented features or hacking. For example, to connect all household appliances into single distributed computation network, which could do useful computations (e.g. host a covert website; calculate chemical/biological reactions; mine cryptocurrency; initiate DDoS-attacks upon other networked systems; run arbitrary programs; be used as ersatz PC; etc). Their inner data storage (flash drive, hard drive, etc) could be used to store all sorts of files, as extra disk space or for confidential data (since household appliances aren't meant to store arbitrary data or run arbitrary programs, they're unlikely to be attacked or searched). Some devices connect through the cellular network, or similarly independent communications with the manufacturer/vendor/supplied, and so may accordingly have some form of connection that is entirely independent of your own household internet. If they have this and the ability to establish a local Wi-Fi connection, this could result in several unanticipated connotations for the user and/or provider. They should have access to variety of interesting places (e.g. the servers of their manufacturer, from which they download updates, and to which send error messages). The problem with this, is that "smart" appliances are often comparable or weaker than micro-PCs (like "Pi" variants) — while often costing more than a combination of a normal appliance and a Pi micro-PC — making such devices not viable for computations, unless either user already has smart devices in his house, or a device requires abnormally high computing power for it's job due to over-engineering (some multifunction printers may have storage capacities ranging from significant fractions of gigabytes up to terabytes, as a means of buffering documents being scanned/printed).
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[edit]
- [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[edit]
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. In ordinary water as found under mundane circumstances on Earth, 99.7% of all such molecules will be the 'normal' version of water: two atoms of 1H and one atom of 16O. (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.
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 Ih, 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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Having network access can have some use for a dehumidifier, e.g. to remotely set the target humidity level, or get notifications when the water tank needs to get emptied. But having devices that depend on a specific app or a vendor-provided remote service risks having a useless device after a while ... --134.102.219.31 13:19, 30 June 2025 (UTC)
- Humidifiers typically have a physical control to set a target humidity level, and even the most basic models turn off when the water tank gets full. Since humans can't really tell the difference between 40-60%, which is the range of most humidifiers, there is no need for a remote control to change the humidity levels on a machine. As for the water tank, regular use of the humidifier will teach the user about how long it can run before turning off and needing to be emptied. 136.62.110.93 (talk) 13:58, 30 June 2025 (UTC) (please sign your comments with ~~~~)
- Though there might be a device that attempts to do both jobs, note that this is a dehumidifier (as you functionally refer to) and not necessarily also a capable humidifier (as you namechecked it). 92.23.2.228 17:53, 30 June 2025 (UTC)
- uh, I forgot the leading 'de' . we're currently dealing with a semi-functional a/c unit in our business warehouse/office space. having to keep running the DEhumidifier to keep the temp reasonable during work hours. not enough condensate capacity to run over night, so it shuts off after about 10-12 hours. at least it runs on simple mechanical controls with no reliance on wi-fi 13:40, 1 July 2025 (UTC)
- i had a good laugh at this comic, as i am designing dehumidifiers and they include wireless connectivity.....but there are reasons for this. But is more for monitoring, like e.g. in a water damage case the resoration company can see if the room is dry without having a technician drive to the location.
- Though there might be a device that attempts to do both jobs, note that this is a dehumidifier (as you functionally refer to) and not necessarily also a capable humidifier (as you namechecked it). 92.23.2.228 17:53, 30 June 2025 (UTC)
- this comic will end up on our wall, together with xkcd:242 The Difference--
84.46.99.18 06:41, 1 July 2025 (UTC)
"if they discover a new kind of water" - There are several varieties of heavy water (common Hydrogen deuterium, tritium; common oxygen, various other isotopes), not to mention several [wiki:Phases of ice|phases of ice]. 64.201.132.210 20:31, 30 June 2025 (UTC)
- I restored the part about phases of ice, because dehumidifiers do deal with ice (when icing up, and if the ambient temperature gets low). Mostly put it back because I thought a mention of ice-nine would be fun. 2600:387:4:803:0:0:0:B2 20:42, 30 June 2025 (UTC)
Is the salesman Hairy? Seems similar but not quite enough hair, I'm not sure who he's supposed to be --Darth Vader (talk) 21:17, 30 June 2025 (UTC)
hydrogen peroxide.--me, hi (talk) 01:12, 1 July 2025 (UTC)
- It's made of the same elements, but it isn't water. BunsenH (talk) 02:29, 1 July 2025 (UTC)
- still liquid. --me, hi (talk) 21:44, 2 July 2025 (UTC)
- Hydrogen peroxide is not to be confused with Dihydrogen Monoxide --134.102.219.31 11:30, 1 July 2025 (UTC)
- "Two guys walk into a bar. One says, 'I'll have H₂O.' The other says, 'I'll have H₂O too.' The second guy dies.", Anonymous --Ptdecker66 (talk) 14:10, 1 July 2025 (UTC)
Ice-nine is mentioned once in the trivia section. Did the user that added that mean to say ice-IX, were they unaware that ice-nine is fictional, or was it meant to be a joke? I thought that any "jokes" in the explanation were supposed to be technically factual, such as adding [citation needed] to a plainly obvious statement. Please forgive me for asking this stupid question. 47.14.13.170 01:22, 1 July 2025 (UTC)
I just mentioned acoustic-based/light-based attack vectors and that patches might circumvent them. I've heard of them used against other devices, but never against a dehumidifier. Citation needed? 181.214.218.75 17:36, 1 July 2025 (UTC)
NOTE: water molecules do NOT exchange hydrogen ATOMS. atoms contain both protons and electrons. even your reference states that water molecules exchange PROTONS, not atoms. 2607:fb90:8a91:4e30:3c86:6f12:78c6:fe52 (talk) 00:30, 2 July 2025 (please sign your comments with ~~~~)
Does it at least support water conservation? StapleFreeBatteries (talk) 06:06, 2 July 2025 (UTC)
- It probably supports water conversation, at the very least. 92.23.2.228 18:18, 2 July 2025 (UTC)
Improving the functioning of a dehumidifier does not require a new type of water. It could for example have a variable speed motor and prop-expansion valve. It is impossible to explore the full range of possible operations, so continuing engineering may be able to find better ways to operate the hardware without alterations. I worked on industrial equipment; we would routinely rollout software upgrades that would tweak a few percent improvement in installed equipment. 76.180.44.2 16:35, 5 July 2025 (UTC)
I can't make much sense of the new "Yet there is a method" paragraph. It seems to be saying that if programmability was added to absolutely everything, stuff could be done with it, but probably not very much. It's kind of like saying that if vitamins were added to absolutely everything, you could get some more nutrition by chewing on random objects in addition to the food you eat. It's a somewhat weaker argument than the usual "citation needed". BunsenH (talk) 04:07, 7 July 2025 (UTC)
- That's the only idea i currently have about benefits of Wi-Fi in dehumidifier - it has no benefits for it's intended function, but does benefits for it's undocumented functions. Such smart devices can work as weak-ish computers with programmability; not very much - but they're already in your house, so you're getting that as a bonus - and you likely have many such devices in home, so they could be assembled into actually strong computation network. --SMGmsgsgd (talk) 13:45, 7 July 2025 (UTC)
- I'm still not seeing it. Exactly the same argument could be made for adding computational power to anything: shoes, printed books, squirrels, bananas, etc. It isn't an argument for adding such abilities to a dehumidifier in particular. BunsenH (talk) 18:16, 7 July 2025 (UTC)
- I just think it's all rather irrelevent, that bit. Some (separate) instances of what uses a wifi (or mobile-internet) connection could convey, and perhaps how they can be subverted, managed to get rolled into this. But some of it seems to be aimed at subverting the owner's expectations, some aimed at subverting the manufacturer's intended uses, etc, and all it really shows is that something that probably doesn't need an internet connection and reprogrammable firmware probbly would be best off without it. The paragrah has grown, admittedly with my own input (or corrective edits) as two parts of that, and probably could do with a good looking at to make sure that it has a more focused message. Or is perhaps split up into several seperately more focussed paragraphs that each is more narratively self-consistent. OTOH, I'm also not sure that anything would be lost by deleting it, perhaps remembering some few aspects of it as minor edits to other bits. 92.23.2.228 18:50, 7 July 2025 (UTC)
- I'm still not seeing it. Exactly the same argument could be made for adding computational power to anything: shoes, printed books, squirrels, bananas, etc. It isn't an argument for adding such abilities to a dehumidifier in particular. BunsenH (talk) 18:16, 7 July 2025 (UTC)
By the Numbers[edit]
Is anyone intrigued by the sheer numerical properties of the ordinal comic numbers themselves? This one, for example, is a prime number: 3109 is only divisible by itself and 1. I would be unsurprised to learn that Randall adds a layer of meaning based on significant or unusual sequence numbers. Has anyone else tried to keep track or decode such things? As of this writing, the next "Prime XKCD" will be 3119. Elizium23 (talk) 08:48, 12 July 2025 (UTC)
- There have been notable number-related comics (or absence, in the case of 404), so there's always going to be some cases of playing to the number of the comic (or not).
- But 3109 is the 445th prime number, and I doubt that such a numerical significance has been designed-in/easter-egged to many (if any?) of those. The thing is, prime number keep happening (at this stage in the game, very roughly every seventh number... (between the prie at 3001 and the one at 3203, the actual gaps are (2x)2, (5x)4, (3x)6, (2x)8, (2x)10, (4x)12, 14, 16, 20, and 26; so by another count the median gap is 8, but the two '10's gaps in that ~200 range happen to be either side of 3109 - make of that what you will).
- Fun to work out, even if I'm just not sure that means anything. Not even the most obvious 'analysis'. Chief amongst the many numerical 'facts' is that (405 excepted, perhaps) every comic's number is exactly one higher than the one for the comic before. How totally amazing is that, eh..? :P 92.23.2.228 20:22, 12 July 2025 (UTC)
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