Talk:2651: Air Gap - Revision history

172.70.210.145: Reply

2022-07-30T01:01:32Z

172.69.33.245: reply

2022-07-30T00:46:22Z

172.69.33.199: Cleanup

2022-07-29T22:57:59Z

Cleanup

172.69.33.199: Higher filament bandwidth

2022-07-29T22:56:25Z

Higher filament bandwidth

172.70.211.88: Flying drone rechargers

2022-07-29T22:09:28Z

Flying drone rechargers

D5xtgr at 19:44, 29 July 2022

2022-07-29T19:44:09Z

162.158.159.95 at 17:11, 29 July 2022

2022-07-29T17:11:57Z

Barmar at 15:24, 29 July 2022

2022-07-29T15:24:51Z

Kynde at 09:22, 29 July 2022

2022-07-29T09:22:40Z

Kynde at 09:16, 29 July 2022

2022-07-29T09:16:18Z

← Older revision		Revision as of 01:01, 30 July 2022
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	What is the highest wattage commercial opto-isolator, and how can I get one mounted from the ceiling in my bedroom? [[Special:Contributions/172.70.207.8\|172.70.207.8]] 14:10, 28 July 2022 (UTC)		What is the highest wattage commercial opto-isolator, and how can I get one mounted from the ceiling in my bedroom? [[Special:Contributions/172.70.207.8\|172.70.207.8]] 14:10, 28 July 2022 (UTC)
		+	: Ordinary florescent bulbs or neon tubes are close, the electrical circuit being isolated to flow through a gas which only becomes ionized and thus conductive in a way which causes it to emit light. But the signal stays as electrical without any intervening photons. You probably don't want a laser BBQ on your bedroom ceiling, but then again, the military gear referred to below isn't commercial, as it would never pass laser safety certifications. [[Special:Contributions/172.70.210.145\|172.70.210.145]] 01:01, 30 July 2022 (UTC)

	I wonder if it's worth noting the significant understatement within the title text, where it says "the bitrate does drop a little" in contrast to the severe and drastic drop in bitrate that would actually occur, especially in light of today's typical Internet speeds. It might not be worth mentioning, but it struck me as a humorous understatement of the true impact. [[User:Ianrbibtitlht\|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht\|talk]]) 14:25, 28 July 2022 (UTC)		I wonder if it's worth noting the significant understatement within the title text, where it says "the bitrate does drop a little" in contrast to the severe and drastic drop in bitrate that would actually occur, especially in light of today's typical Internet speeds. It might not be worth mentioning, but it struck me as a humorous understatement of the true impact. [[User:Ianrbibtitlht\|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht\|talk]]) 14:25, 28 July 2022 (UTC)

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 [[User:Torge|Torge]] ([[User talk:Torge|talk]]) 15:11, 28 July 2022 (UTC)
 : Interesting! [[Special:Contributions/172.70.142.21|172.70.142.21]] 06:51, 29 July 2022 (UTC)
 Nobody caught on that powerline networking is about sending data through powerlines? or that a crude opto-isolation setup could effectively scrub it? Where my networking geeks at? I am disappoint [[Special:Contributions/172.69.71.51|172.69.71.51]] 15:19, 28 July 2022 (UTC)

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 Most of the bulbs in my house (before compact flourescent and LED) were 75 Watt or 100 Watt. 50 Watt would be a very dim bulb.
 : Mice wouldn't agree. [[Special:Contributions/172.70.214.43|172.70.214.43]] 05:05, 29 July 2022 (UTC)
-::In Denmark 60 Watt was standard, with 100 and 150 possible in some lamps.
+::In Denmark 60 Watt was standard, with 100 and 150 possible in some lamps. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:22, 29 July 2022 (UTC)
 --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:22, 29 July 2022 (UTC)
 There are actually usecases for optical power links. For example electric field probes use this: https://www.raditeq.com/products/electric-field-probes/
 --[[User:Casandro|Casandro]] ([[User talk:Casandro|talk]]) 08:10, 29 July 2022 (UTC)

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 ::: Maybe this helps? https://ieeexplore.ieee.org/abstract/document/5625426 [[Special:Contributions/172.70.142.21|172.70.142.21]] 06:51, 29 July 2022 (UTC)
 :::: Yes! [https://tigerprints.clemson.edu/cgi/viewcontent.cgi?article=1961&context=all_theses Figure 1.10 seems to suggest that frequencies above 10 Hz are filtered,] and that seems consistent with Figure 3.14, in that recovery time is a tenth of a second (though drop-off "cooldown" time is much shorter.) So if I remember my {{w|Binary Golay code|modem math,}} even with the most sophisticated coding, anything more than 640 bits per second should be impossible. [[Special:Contributions/172.69.33.225|172.69.33.225]] 07:39, 29 July 2022 (UTC)
 I'm almost tempted to suggest that this should be an (honourary) addition to the Cursed Connectors comic-collection. [[Special:Contributions/172.71.94.187|172.71.94.187]] 14:56, 28 July 2022 (UTC)
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 There are actually usecases for optical power links. For example electric field probes use this: https://www.raditeq.com/products/electric-field-probes/
 --[[User:Casandro|Casandro]] ([[User talk:Casandro|talk]]) 08:10, 29 July 2022 (UTC)
-::Some drones can be recharged in the air by lasers, but that's a really obscure application only the military needs, and then only as a contingency backup in most cases, but there were flying demos by companies interested in the space over the past decade. [[Special:Contributions/172.70.211.88|172.70.211.88]] 22:09, 29 July 2022 (UTC)
+:Some drones can be recharged in the air by lasers, but that's a really obscure application only the military needs, and then only as a contingency backup in most cases, but there were flying demos by companies interested in the space over the past decade. [[Special:Contributions/172.70.211.88|172.70.211.88]] 22:09, 29 July 2022 (UTC)
 I think it might be possible to construct a scenario where this could have some security benefit, albeit not one that justifies such poor efficiency. Suppose you have an embedded system running off USB power to perform some cryptographic task, but the USB port the cable's plugged into is under the control of an attacker who has it instrumented to sample the power consumption at a high frequency. He can perform {{w|power_analysis}} if the load changes based on the operations performed by your device, but the setup in the comic should prevent information from leaking upstream in this manner. [[User:D5xtgr|D5xtgr]] ([[User talk:D5xtgr|talk]]) 19:44, 29 July 2022 (UTC)

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 There are actually usecases for optical power links. For example electric field probes use this: https://www.raditeq.com/products/electric-field-probes/
 --[[User:Casandro|Casandro]] ([[User talk:Casandro|talk]]) 08:10, 29 July 2022 (UTC)
 I think it might be possible to construct a scenario where this could have some security benefit, albeit not one that justifies such poor efficiency. Suppose you have an embedded system running off USB power to perform some cryptographic task, but the USB port the cable's plugged into is under the control of an attacker who has it instrumented to sample the power consumption at a high frequency. He can perform {{w|power_analysis}} if the load changes based on the operations performed by your device, but the setup in the comic should prevent information from leaking upstream in this manner. [[User:D5xtgr|D5xtgr]] ([[User talk:D5xtgr|talk]]) 19:44, 29 July 2022 (UTC)

← Older revision		Revision as of 19:44, 29 July 2022
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	There are actually usecases for optical power links. For example electric field probes use this: https://www.raditeq.com/products/electric-field-probes/		There are actually usecases for optical power links. For example electric field probes use this: https://www.raditeq.com/products/electric-field-probes/
	--[[User:Casandro\|Casandro]] ([[User talk:Casandro\|talk]]) 08:10, 29 July 2022 (UTC)		--[[User:Casandro\|Casandro]] ([[User talk:Casandro\|talk]]) 08:10, 29 July 2022 (UTC)
		+
		+	I think it might be possible to construct a scenario where this could have some security benefit, albeit not one that justifies such poor efficiency. Suppose you have an embedded system running off USB power to perform some cryptographic task, but the USB port the cable's plugged into is under the control of an attacker who has it instrumented to sample the power consumption at a high frequency. He can perform {{w\|power_analysis}} if the load changes based on the operations performed by your device, but the setup in the comic should prevent information from leaking upstream in this manner. [[User:D5xtgr\|D5xtgr]] ([[User talk:D5xtgr\|talk]]) 19:44, 29 July 2022 (UTC)

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 :I agree that it reminds me of some of those. But it could never be added to the category, as it misses the cursed connector name and number. But I have added a mention of the similarity here above, and also mentioned it on the [[:Category:Cursed Connectors]] page. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:22, 29 July 2022 (UTC)
 :It's a cursed ''dis''connector. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:24, 29 July 2022 (UTC)
 Yes, solar panels can transform electrical into electromagnetic signals. It is more on the side of the incandescent bulb that the capability to receive and forward these signals is missing. My source: https://www.youtube.com/watch?v=TGUteH93xNo

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 ::: Yes, thanks :) although there is a tiiiiiny advantage to the direct link without the template (the way I said), <code><nowiki>[[wikipedia:Pipe (computing)|]]</nowiki></code> becomes [[wikipedia:Pipe (computing)|Pipe]] whereas <code><nowiki>{{w|Pipe (computing)}}</nowiki></code> becomes {{w|Pipe (computing)}}. The pipe trick strips out the disambiguation parts of the title according to [[Wikipedia:Help:Pipe trick|some rules]]. --[[User:NeatNit|NeatNit]] ([[User talk:NeatNit|talk]]) 12:30, 28 July 2022 (UTC)
 :::: Why not <code><nowiki>{{w|Pipe (computing)|pipe}}</nowiki></code>? [[Special:Contributions/172.70.214.95|172.70.214.95]] 15:18, 28 July 2022 (UTC)
 It is missing that air-gapping the power supply would protect your home from voltage surges in the power network caused by lightning strikes. Depending where the lightning hits the power network, there may be no fuses protecting your home or single fuses may fail to protect you. --[[Special:Contributions/172.70.246.115|172.70.246.115]] 07:57, 28 July 2022 (UTC)