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Apple Lightning (nyansatan.github.io)
597 points by captn3m0 88 days ago | hide | past | favorite | 229 comments

I'm curious -- what's the reason for something seemingly as simple as a Lightning cable to have chips inside of it?

For most of computing history, I was generally under the impression that cables were "dumb" -- each pin connects to a wire which connects to a pin on the other end. There's fancy bundling and twisting and whatever involved, but it's still ultimately just conductive wires.

When did cables start getting chips, and why? Did Apple start it or somebody else? Is it solely to try to prevent third-party manufacturers? Is it for the cable to announce to the port that it supports certain specifications of power or data? (But why would that require a chip instead of just some kind of "dumb" extra pin that has some basic electrical property that can be read?) Is it something else?

I mean I understand why certain dongles have chips, because they're connecting between sets of pins that aren't 1-1 or even in the same data format at all. Or why the same might be true for USB-C to Lightning.

But for cables to go from "dumb" to "smart" seems like it kind of breaks all expectations of what a cable even does, and therefore how a consumer will even know what to purchase -- which, of course, has famously been a HUGE issue with USB-C.

Would it be better for us to go back to dumb cables without chips? Or are there good reasons why this is the future, where at some point we'll expect all computer cables to have them?

Lightning added chips that weren't necessary IMO. You don't need smart control over the low voltages/power that go over a lightning cable. Lightning chips were likely more about control.

USB-C _does_ require e-marked cables in certain cases where passing large amounts of power over a thin cable could be dangerous. I don't believe these chips are proprietary nor expensive - just marking silicon that replaced the old resistor system that was somewhat brittle and often wrong.

Thunderbolt 3 (and probably USB4) requires chipped ('active') cables at lengths over 0.5m, but considering you're pumping 40Gbit of data over it, it kind of makes sense.

For Lightning, yeah, there's basically no reason except for the 'Made For iPhone' program, and it isn't even effective at that since Chinese cable makers just clone the keys of the official stuff.

Couldn't whatever EQ/delay compensation is performed by the chip just be moved to the PHY?

The chips in MFI program were pretty much DRM.

It could, but it already was hard for Intel to get Thunderbolt adopted because the controller is rather expensive. My guess is that they assumed most people would only use it for short distance connection and thus they moved the cost of EQ to chipped cables for those who would truly need it.

Indeed, I believe 40Gbit Ethernet doesn't need active cabling either.

Not exactly - at very short ranges, you can use DAC cabling, "Direct Attachment Cable". Those directly connect SFP signals, but afaik they still have circuitry inside its just easier because the cable is known length and characteristics - in exchange the cable is rather thick and unwieldy. Generally it works well inside rack for connecting servers to ToR switches and that's it.

40Gbit DAC is even more annoying because unless the cable is a bit more active, it's essentially 4 10gbit DAC in one sheath.

there is no such thing as 40G ethernet. you can see this easier with optical - there are literally 4 cables inside the one thick cable. you're talking about quad ports - 4x 10G connections in one wide QSFP. in fact, all a breakout cable does is take the 4 wires in that 40G cable, and unwraps them. Ethernet currently goes to SFP28, which is a 25G connection. fibre channel (as in SAN, not LAN) in theory currently goes to 128G, and in practice you can buy buy hardware that goes to 64G. FC cannot run over copper.

Second, yes, some does require active cables with DAC. which does not stand for "cable" like the other comment says. DAC is direct attach copper (as opposed to optical). Without an active cable you're limited to 5 meters, although you can risk it and get a 7 meter passive cable. usually, 7m is already active, and 10m+ is guaranteed to be active. The reason you can even do 10G over copper is because it's cat6. Have you seen that cable? It's twinax - more like the cable from your TV antenna. That's not viable for a phone.

What you are talking about is 10G base-T. That does not need active cabling. but again, you can't compare that to a tiny thin lightning cable.

You're correct and shouldn't be downvoted.

If you're considering downvoting them, there's news articles about when Apple caved and allowed 3rd party cables.

Just waiting for a time when we can say this about Apple and third party repairs.

The independent repair program is bullshit and is just a marketing move to try to appear good and avoid regulation being passed. Louis Rossmann (a popular unauthorized repair shop owner) explains it: https://www.youtube.com/watch?v=0rCUF-V1esM

I'm more concerned about what's not clarified: What are the costs to these independent repair specialists? Are they being charged exorbitant fees to keep Apple's in-house repair options more competitive? What cut is Apple taking, if any, per repair? Does Apple guarantee a repair made through these independent providers isn't going to result in a bricked device down the road? Can consumers see a cost breakdown of parts and labor like we can with repairs to non-Apple devices? And what criteria is being used to determine an "authorized" third party? Is that criteria biased against critics of Apple's platform? Is this considered a "license to repair", and if so, under what conditions is Apple reserving the right to revoke that license?

I have more questions than anything else.

Lightning cables have exposed contacts - While at 5V, this does not pose a significant shock risk, if full current were available, brushing the connector against metal could result in sparks and damage to the connector or power supply. Additionally, if the connector gets wet, the DC voltage will result in electrolytic corrosion. This still does happen even with the limited current provided before the handshake, just slower. (Don't!!!) try charging a phone with official cables and a power bank in the rain or letting a plugged in lighting cord's lightning end sit in some soup

Cables with electronics in them are useful for protections like this, and to facilitate safe interoperability of multiple voltage and current sources and sinks like on USB Type-C. The question becomes, is the protocol implemented in a simple, open consumer friendly way or is it implemented with other nasty antifeatures.

Couldn't all of the protections on current delivery be implemented in the interface on the other end of the cable, though? This is the approach taken by basically every other standard for negotiated power delivery. Even things like 802.3af which manage to deliver 48v at nearly an amp and with the complicating case of many valid devices not really tolerating any current delivered.

The other end being USB-A power adapters? There’s a vast number of those of varying quality. Some have zero logic and just output 5V/1A. No way they could be trusted for this purpose.

call this a “safety in depth” approach

No I think the GP meant the port on the iPhone as the “other end”. In other words, why not have all of the protection logic built into the phone?

just as an example, imagine you end up putting a fuse in the cable. If the fuse blows, then the cable can be easily replaced. A chip in the iPhone.... not so much.

Though likely there's something in the phone _as well_ as the cable.

If the cable is dumb, it can’t switch the +5v power coming from a USB supply. If it can switch it, it’s not dumb.

So we should buy expensive cables and cheap power supplies?

Those cheap power supplies are ubiquitous, so it's more about Apple building their cables to exist in the built environment than dealing with the fallout of consumers busting up their expensive phones by charging them on whatever's lying around.

Guarantee there was a consumer study where they compared reactions between these scenario.

The manufacturers knows that if it’s their product in contact when a user is shocked, they will get some blame even if it’s “really” the sketchy power supply’s fault. And since some cables have these safety features already, anyone making cables without them will appear extra negligent when bad things happen.

The world is unfortunately not very efficient.

There was already a huge installed base of cheap power supplies

The other end of the cable is generic USB and can often be a naked, logic-free 5V supply.

I’ve cut the ends off way too many USB cables just to expose those red and black wires.

And surprisingly many cables even have just those two wires inside of them and can't carry any data

Isn't direct current component ignored by default just because Ethernet devices are galvanically isolated? I thought even if you applied some DC voltage to Ethernet without proper PoE negotation, nothing would happen at all.

In a nutshell: EMI (Electromagnetic Interference) is the main reason why cables got smart in the first place.

Many people in IT think, that data is just 1s and 0s. But in reality we are living in a physical world and as such some form of power is used to transmit those 1s and 0s. This power may is electrical power in terms of voltages with defined generated current or in terms of current with defined voltages (20mA communication heavily seen in industrial equipment). If you have a slow communication link, EMI and other environmental thinks like temperature is not much of an issue. But as faster you like to communicate you need to cope with those things. The electrical contacts in the connectors doesn't help. So people started to put the transceivers into the cables. Those transceivers with additional electronics like ringing suppression circuitry and other "magic" are then best fitted for the desired cables for the desired environments. Then you started to makes those cables smart like to detect the capabilities of the cables like is it really possible to talk at 10Gbps or is it more a cheaper type where 100Mbps is the max. As more smarter those cables get people get creative to put other things in it like "hey, the cable could become a converter as well".

The potential EMI of cables you're talking about can be fixed with good shielded cables, they don't need active chips inside them.

Shielding helps. That is correct. But it does not help with ringing, temperature and other such kind of problems. And shielding is expansive.

What shielding does not help as well is contacting problems because of corrosion or dirt. We are talking about a consumer product and not a well designed any lay out wiring by some system integrator. Consumers are doing all kind of bad things to connectors and will complain if it does not work.

And how does having active chips in a 1m cable help?

by replacing a cable instead of taking apart your iphone and soldering the chip in the phone when an electrical spike comes through from your open contact getting water on it. but you're asking about throughput. the reason active cables exist is because the amount of interference in a cable varies - that little sheath of tin foil in a lightning cable does almost nothing. you need an axial cable for that - which is what ethernet uses for passive direct connection. it's as thick as the coax cable for your tv antenna. your idea I guess is to plug in that thick non-bendable cable into your phone? or is it to put that chip into every usb-A power source in the world? or is it to only use approved apple usb power supplies - instead of the millions of plugs out there at airports, hotels, laptops, existing ac/dc converters from hundreds of vendors? so which of these is your plan instead of the chip in the cable?

I know, I know, usb cables don't need a chip inside, why does lightning. because usb cables are a useless random mess. lightning cables are not - they run at the guaranteed speed, they charge at the guaranteed watts, and they have no issues with shorts despite having contacts exposed and reversible, unlike usb. and usb-C? well, there are active cables available for that, which tackle the issues described with a chip in the cable. just like lightning does.

> In a nutshell: EMI (Electromagnetic Interference) is the main reason why cables got smart in the first place.

Considering the main use case (almost exclusive use case) for lightning is for charging and nothing else, I wonder why they have to be so complicated? Shouldn't charging cables work with Vcc/Gnd only wired and a dumb power 5V/2A source? Why is my phone doing some complex detection/negotiation of cables/chargers when I plug it in? Why is a charger considered an "acceessory"?

Lighting is for charging and nothing else? Really?

Tell that the people, who want to connect their professional microphone to make TikToks. Tell that the people, who want to connect a stick drive to offload their videos. Tell that the people who provide different accessories.

Lighting has evolved from the 30-pin Dock connector. The 30-pin Dock connector was the idea to combine charging, USB, and some analog stuff into one single connector. At that time USB provided only 5V and 200mA. Apple was one of the other who improved USB charging by allowing more power. But for the sake of compatibility, you cannot just do this, you need to negotiate it. It is like every USB up to USB3 starts in USB1.1 to negotiate the possibilities.

So, Lighting was not developed out of thin air. It was developed with a history, like many many other communication protocols and standards. Even as Apple is known for cutting of old ties easily, if you look really deep into the details, you will always find compatibility to old out-dated technologies. Its like you still find the good old 8051-core in many things, like even dead simple and cheap charge controllers.

While you might only use Lightning for charging, it is an accessory port. It can transmit data to computers, it can talk to SD cards, it can output HDMI.

You could argue you that you don't need any of those features, but Apple disagrees and that's why lightning is not just a 5V DC jack.

My argument (or question) isn't that Lightning is useless or that I don't need it, but that charging shouldn't require a lot of complex communication. I don't understand what it is about charging that requires both ends to have microcontrollers

It doesnt actually matter what the almost exclusive use case is, the sheer ability of being able to transmit data in this case and other available uses makes the apparent need of a chip. Keep in mind these chips bring safety to the exposed pins and some negotiation is needed to understand whats on the other side of the cable in order to better handle it. (That and to make it possible to control 3rd party market accessory) A charger is considered an accessory because it is merely a utility for a device, it is made to charge stuff. Take a purse for example, it merely holds stuff and nothing more, you can change a purse and the other one will do the exact same job.

> A charger is considered an accessory But because it is merely a utility for a device

Yes I understand the reasoning behind it, but I don't understand why it's not seen as a much more important feature to be able to load from anything anywhere so long as the +5V and GND pins are working, regardless of what power source and cable it is.

That there is complexity when the lightning cable and connector is used as a data transfer cable I understand. I don't understand why the charger mode isn't dumb as rocks.

Because destroying chargers with too much current, or lighting cables on fire is a bad PR?

I have a lot of cheap chargers, and they give out all sorts of crazy stuff. One drops the voltage to like 3.5 volts with 1 volt of ripple under load. Another shuts down the port completely if you draw >.6A.

It is really hard to tell how much current can one draw safety.

Primary use-case for a smart phone is the web-browser and networking array.

That doesn’t mean you can remove the microphone.

Optimising the common case in this instance will remove all other possibilities.

You don't have to remove negotiation and complexity from the system when it's used for data. My question isn't why those systems are there so much as why they are needed for the charging use case. E.g.: why do chargers even need more pins wired than +5V and ground? Is there really such a large benefit from making chargers "smart"?

The chip's responses are how the iPhone knows what device / cable type is connected to the port- at least that's what I understand from this.

Why wouldn't the device ask the port directly? A chip in the cable means that the device asks the cable, which then asks the device.... why not cut out the middleman?

One use-case comes up in the article: the chip in the cable is able to probe information from the device even when the device is unpowered, essentially acting as a microcontroller grabbing some of the device's less-guarded peripherals for itself.

If the device is dead, then it can't ask the port.

This is also tied to fast charging (and whether the device will support it)

Couldn't it provide the low power until the device is powered enough to answer the fast charging question?

Also, wait... if the device is dead, how does the CABLE know that fast charging is supported by the device?

I think the link describes this tangentially. The minimal 10mw - 15mw current that high-five allows on a cable that hasn’t completed a handshake is enough to charge the capacitor for secure boot and trident which then can handshake with 0x74 to receive 5v 1a source. When the kernel boots the rest of the handshake process can be completed to increase the current.

That’s at least my understanding from the document.

Is it solely to try to prevent third-party manufacturers? Is it for the cable to announce to the port that it supports certain specifications of power or data? (But why would that require a chip instead of just some kind of "dumb" extra pin that has some basic electrical property that can be read?) Is it something else?

My theory is that it started as the former and then they realised it would seem less suspicious and more friendly to also use it for the latter.

In a nutshell, the answer is that the Lightning cables just seem simple, but they're not.

How would you maintain such a margin on the cables if they could be "dumb"?

The last time I looked, the money Apple earned from the entirety of the MFi program — not just cables, but every single third-party Apple accessory on Earth — made up less than one half of one percent of their annual revenue. It's such a vanishingly small part of their business.

It's far more likely that the purpose of MFi is to make sure that any officially licensed accessories aren't pieces of shit that Apple will cop the blame for. Most users aren't going to blame the cable manufacturer when their phone won't charge properly, since the vast majority of people have no idea about the complexities of modern charging protocols, so they're going to mistakenly think the phone is at fault and blame Apple.

> every single third-party Apple accessory on Earth made up less than one half of one percent of their annual revenue

That makes me even more angry about the ridiculous price of these accessories

Considering they're already being ripped off anyway, and most consumers don't know they're "smart", the margins would be higher selling a "dumb" cable that costs less to make, at the same price as they sell them at today.

I love that the protocol uses the string “BREAK”. Old teletypes, and in particular the iconic ASR-33 had a key marked “BREAK” that was not a character; it simply held the line open. This could be interpreted by the person on the other end as a sign to reset what was going on and start again, or really anything that might have been pre-agreed.

With the advent of computing, and connecting teletypes to computers, it was often used to trigger an NMI. Multics and the rainbow books cited it as a way to make sure you were talking to the “real computer and not some program impersonating your computer (since it wasn’t an actual character there was no way for a normal program to even see it much less generate it. The terminal controller/channel controller could see it though and notify the monitor (what we call the “kernel” these days).

UARTs and serial protocols are still in very widespread use. A large proportion of all embedded devices use them, which is arguably the majority of all computing systems sold.

What you're implying is historical is still current.

Yep, and I know that UARTS still have built in break detection but keyboards don’t have a BREAK key, or any rainbow book style “secure key to signal the computer” function any more. Even the power switches on Mac laptops (and I assume others), phones etc are soft functions.

I haven’t designed an embedded device or serial protocol that used break since, well, ever. That’s why I was tickled to see this.

Edit: just saw your uname — my use of the term “tickled” was coincidental

I bet most of the information in this article was already known by others, mostly in the repair as well as the 3rd-party accessories businesses, and either wasn't publicised or was not in English. I still remember the announcement in a Chinese BBS a long time ago when the first company in Shenzhen cracked the protocol --- a few weeks after Apple started using Lightning.

Apple seems to like using 1-wire buses; here's another application of one: http://www.righto.com/2013/06/teardown-and-exploration-of-ma...

You're not wrong about your information, but interestingly your criticism parallels that commonly levelled against Apple itself - that Apple's innovation was "was already [achieved] by others". However, it wasn't yet presented in a nice, easy to consume package all in one place - which is sometimes just as significant as the raw engineering itself.

It's testament to the noteworthiness of both Apple and this article that here we are talking about it all - about efforts cobbled together from other parts.

Right, this seems to be mostly reverse-engineered personally. I am sure that the people replicating debug cables have a fairly good idea of what’s going on inside of them.


> To enable full current, 0x74 request must be issued by Tristar and processed by HiFive. For SecureROM/iBoot that's enough

I wonder if that means, in a pinch, you could turn off the device to use an uncertified charger that iOS would block.

Actually, yes. At least anecdotally– I _had_ to do this when my iPhone 5's lightning port was damaged.

When traveling overseas a cheap charger died, partially frying my lightning port. The phone completely refused to charge and I grew more and more desperate as the battery slowly drained over the next day before eventually dying. Now trying again to charge the dead phone had a surprising result: it actually charged enough to boot up! Ridiculously: it then stopped charging once booted and drained again in about 2 minutes.

The solution I developed was to plug it in _then_ power it off and it would charge (slowly) while completely powered down. Removing power for even a moment would boot the phone and stop charging.

I'd absolutely guess that, in a pinch, you could charge your modern iPhone with a non-working cable if you did the same procedure: plug in, power off, let charge while off.

> I'd absolutely guess that, in a pinch, you could charge your modern iPhone with a non-working cable if you did the same procedure

Or you charge it wirelessly (Qi charging).

Unlikely, even if you shut the device down when you attach a charger it goes into either a semi-on state or just turns on entirely. Even if you shut it down while it’s plugged in.

I thought the “semi-on” state with the battery display was still just firmware and not full iOS. If not, what exactly is it booting to display that? Surely not an ordinary kernel?

My experience is with the MTK platform but Apple may be similar; in which case the battery display is done by neither "firmware" nor the full OS, but an intermediate component:


I believe they are just one of the things you can "boot", alongside regular iBoot in the boot partition and loaded appropriately by SecureROM. I'm pretty sure the images at least ship inside IPSWs.

This is correct. That's because the "Charging" screen also sometimes has OEM or carrier branding on, and error messages that might need to be i18n translated eg. "battery failure", "overheat". It's much easier to do that with a separate component rather than give every OEM the ability to flash and recompile firmware.

Side note: I wish that feature could be turned off. Sucks to turn your phone off for the night, plug it in to charge, and it boots back up (it's not the semi-on battery display either, it does a full boot to iOS).

Why are you turning your phone off for the night, is the real question.

I wonder how many iPhone’s have been thrown away because it’s “not charging anymore”. I have had two occasions where my iPhone was not charging and i went to buy a new one, luckily both times shop assistants cleaned the socket, pulled out all the dust balls etc and it was charging again.

I carry a tooth pick for this, but it’s annoying. I’m in the process of switching out my main charging stations for Qi so I don’t have to bother with it...

I love Lightning, long wished it'd conquer all, and expected to hate USB-C.

I kinda like USB-C.

I now half expect Apple's future mobile devices to not have any ports, will just use wireless charging.

Apple AirPods are already pretty amazing. I haven't used any plugin headphones 6+ months. Not even my beloved Shure; which sound fantastic, but hot damn I hate cables.

> I now half expect Apple's future mobile devices to not have any ports, will just use wireless charging.

Wonder where my pocket lint will accumulate if that happens.

In your navel where it belongs

Speaker cavities

Why have speakers when you can just listen on your AirPods :)

Gotta have alarms go off at embarrassing times somehow!

This explain why you can't charge iPhone with "cheap cables".

The only third party brand I trust is Anker.

Someone once commented here on HN that Apple engineering departments get boxes of Anker cables delivered all the time since they’re so much better than Apple’s own. I wish I had saved the link.

This is hardly surprising when you consider that Apple's business is selling a phone, where they generally have to throw in a cable so people can charge it, and Anker's business is selling a cable that you decide to buy even though you already had the one Apple gave you for "free".

Apple could make a better cable, but it's not worth it to do so.

That would make sense _except_ apple sells their cables on their website. They have already chosen to make selling cables part of their business.

What's more likely is that the quality doesn't matter. Lots of people only care about the official apple brand, so apple can get away with selling an interior product for more money.

Sure, they'll sell replacement cables, but they make a lot more "free" cables that sell with their phones and tablets. The cost/quality of the cables they package in phones matters to them a lot. They don't care a ton if additional cables sell well or not. And you're absolutely correct that many people will buy Apple official cables just because they're Apple official.

But here's the thing: Apple can't go selling premium cables and including cheapy ones in their phone boxes. The Apple brand has to be viewed as premium all the time, so they put a mediocre cable both in the box and sold on their website.

It sounds nice at first glance, but I don't think this argument holds up to scrutiny, because it could just as well equally apply to "companies other than Anker" manufacturing cables of this type, and the quality of a great many of those cables is almost notoriously terrible.

I'm certainly not saying Apple produces the worst cable. But that Apple only needs to produce a cable that isn't a detriment to the overall product: It usually works and accomplishes it's task. You aren't buying the iPhone based on the quality of the thrown-in charger cable.

Whereas Anker has distinguished itself as a company that makes quality cables... by selling quality cables.

Well, Apple seems to think strain relief doesn't meet their aesthetic criteria, so that's not surprising.

I don't know what it is, but I've never broken a single Lightning cable since I got my first iPhone in 2016. I still have 2 new-in-box cables from upgrades. But a few weeks ago I was picking up a friend and when she got in my car she said "Why do you have the Apple cable? They're so fragile" and immediately tore the strain relief plugging her phone in.

I had never broken a lightning cable or a macbook charging cable (original magsafe or magsafe2) in maybe a decade of use, but as soon as my kids started using iDevices I've had to switch to buying extra-super-durable ones because Apple's don't stand a chance in the hands of a 7 year old. The Amazon Basics lightning cables with the braided external cover and solid metal housing at the ends seem pretty bomb-proof so far. The housing + strain relief is kind of absurdly long but it's very very sturdy. Anker stuff also seems quite solid.

Edit: I think a lot of people just naturally don't pay much attention to what they're doing to their cables. I used to work at a company where I was pretty much the only one whose MBP power cable wasn't visibly fraying at the ends, and I'm still using the same one 5 years later.

Wait so you dont tie your iPhone cable around a tree and swing on it while your phone is charging! Shocker. I'm in the same boat at you, not a single Apple cable failure in 10 years of using Apple products.

I’ve had two apple cables fail over the past five years despite being mostly just plugged into the charging ports of a powered (anker, hah!) usb hub on my desk. The cable I keep in my bag for when I’m not home is an anker one.

In Denmark most apartment building have a bin for recycling electronics.

I like to open the one on my building, and have a peek to see if there's something interesting. I like repairing (often just resetting) discarded electronics and donating them to people who need them.

Anyway, I find loads of broken Apple cables, but very few plain USB cables.

Do you move the cables often? Do you stuff them in bags for travel? Do your phones get knocked off tables often by cats/kids?

I am guessing usage patterns will explain the difference.

I do all those things. From past discussions I gather the trick is using the phone while charging causes the problem. I tend not to and haven't had issues.

I have noticed with both lightning and macbook chargers that high current draw (and associated heat) while the cable is bent seems to be associated with the cable degrading.

Not using the phone while charging negates this, as does having the cable flat on a table when using the macbook (as opposed to using and charging with the macbook on your lap, where the cable rops down immediately).

Ah! That's the first explanation that sounds plausible (outside of the wear and tear of using it while plugged in).

I think some people are just more meticulous with their stuff than others. I mean by this that it could be considered as going out of their way to make sure there are no tight bends, not pulling on cables, not shoving the cable in a purse whichever way you can, etc. My original iphone cable I bought more than 3 years ago still has its rounded shape as when it was new.

This, combined with poor quality products explains the difference in my opinion.

The only cable that frayed on me was a MagSafe 2, next to the computer connector. The cable is ridiculously thin. It was the adapter for my 15 MBP. In comparison, I'm still using the original adapter of my 2008 MBP and apart from being scratched and dirty, it's still as good as new, cable and all.

What I think happens often is that the cable will be under some kind of rotational stress. I've noticed I have a tendency to always turn the phone the same way, so the cable has a tendency to turn around its axis. It's something I see especially often on corded office phones. Also, cables are often at very tight angles close to the connector, so there beign next to no relief ends up tearing the housing.

I've also seen many people pull on the cable instead of the connector to uplug it. That can't be to good for longevity either.

Same. I should note that I'm a generally thoughtful person and am careful with my electronics. I don't have kids. My cats don't eat cables.

That said, I travel plenty, and I shove cables into my bag like anyone else. I can't think of a single cable for a single product (Apple or non-Apple) that I've destroyed. Some peoples' cables look like they get slammed in a car door twice a day every day.

I don't know what it is about certain people — I also have never broken a single cable ever in 14+ years of using Apple stuff.

Never broken an Apple cable (Laptop, Phone, iPad, etc) in 10+ years either. I grew up as a small child regularly pulling out / pushing in the power cable on a ZX Spectrum, which was a really fragile cable. I guess I learnt a lot of respect for handling cables fairly quickly at a young age from that.

anecdotally it seems to be a combination of using the phone while plugged in and it bends sitting against you/the table/etc (or pulling it tight).. and not plugging and removing the cable by the connector but pulling on the cable.

this is me and i replace these regularly

Same. I really have no idea how people break these cables.

My kids taught me how to break them. Before the kids had iPads our family hadn't broken any, now... it's a weekly thing. Children are professionals at destruction.

Think positive as parent - sigh they are innovative. Destroy and then invent later. Just not in that phase.

I've damaged two magsafe connectors in the last two years. The rubbery plastic protection near the charge point (with the orange/green LED) splits. Then it's super easy to make worse since the split ends catch on things. Like https://i.imgur.com/l2uS8pv.jpg.

I'm pretty sure it's from heat damage from the power. Not mechanical strain. The heat slowly weakens the rubber material to the point of failure.

On one hand you have comments, replies and friends who have never broken a single Lightning cable in the pass 10 years of using iPhone. On the other hand I am may be on my 8th lightning cable over the past 10+ years of iPhone. And this one is from Anker Powerline II. Powerline III is even better but three years in, this Anker Powerline II is doing extremely well.

I have heard somewhere post iPhone 8 there is a "updated" version of Lightning Cable that is suppose to be more durable. But I have no way to fact check this.

i thought this was for green efforts that better materials for the environment don’t hold up to physical use as well

There are certain adapter combinations that Apple doesn't sell themselves, like USB C to Ethernet. IIRC that one is Belkin.

Algolia's search is pretty good ;) https://news.ycombinator.com/item?id=18424630

Having been through quite a few Apple and Anker lightning cables I'd say the Ankers last about three times as long in normal use. The plastic frays and breaks on the Apple ones.

Maybe i'm just lucky, but i've never had an Apple cable break on me. My original iPad 1 cable still works (and is still used occasionally).

Then again, i use my cables for charging, and i never use my devices while charging, so the bending/pulling that destroys most cables never occurs with mine.

One thing that does destroy cables though is a 2 year old kid with a fetish for sucking on the lightning end of the cables. My youngest kid did that for 6 months or so, and every cable he sucked on has a visibly corroded 3rd pin.

I can confirm that it's not true. You get Apple cables.

I've also never had problems with any of my several well-used Amazon-branded Lightning cables. But then again, I've never actually had any problems with the supposedly fragile Apple Lightning cables either.

Yeah, they seem decent.

My partner is always losing cables and ordering the cheapest ones on Amazon, and the thing I hate most about them is that they always make the whole room smell like I dunked my head in a bucket of kerosene. She ordered a chair that had the same issue (Wirecutter approved!) and a jump rope, and who knows what else. Am I just imagining it? I seriously miss the days when I could expect the products I buy to not smell like you'll get cancer just from looking at them wrong.

You need to leave them outside for a couple days to off-gas. It is not just you.

Same here, nothing but high quality cables (and battery packs as well DashCams and robot vacuums, etc) from them and with a wide array of options that I can trust. It was so disappointing when I needed some 90 degree lightning, USB C, and micro-usb cables but they didn't offer any (this may have changed, it's been about a year or so).

Same. I’ve had few issues with anker and when I do they always send out a replacement immediately. Anker is worth the cost and still cheaper / sturdier than OEM.

Add Choetech and aukey to that list. I have tons of their devices and they have the same trust level and quality.

This is way over my head, though fascinating, but I wanted to see if I could understand what part explains it. Is it the "Power Handshakes" part?

Ironically, in our household anyway, there hasn't been an Apple cable that hasn't frayed or deteriorated (fire hazard) to the point where a new one was required. I now only use the third-party braided kind and those have held up quite well. When I was using Apple computers, their charging cables were no different. Maybe they've improved since.

Why would a manufacturer even make a "cheap cable" that didn't charge an iPhone?

Most people barely ever use data over a Lightning cable any more (pretty much only for dongles). Charging's pretty much the only thing most people need.

What cheap cables have you seen that don't charge? This is the first I've heard of it.

I believe lightning became more stringent over time. I have some cables that charged an iPhone 6 but did not charge an iPhone 8.

I just got a cable on amazon that charges around 10% as quickly as my other cables.

Every cheap cable I’ve ever bought has work fine until I damage the cable.

I work with steel though, so I’m rough as fuck though.

its possible to bypass the 'unauthorized cable' with mitsuha reloaded tweak (if your phone is jailbroken)

I exclusively buy ~AU$5 cables from China for my iPhone 7 and SE before it.

They work fine, as do the slightly more expensive ones from the discount stores around these parts.

> The information in this artcile is based on a lot of AppleInternal materials (leaked datasheets, schematics, source codes) I read in a diagonal direction.

What does "diagonal direction" mean here?

In literal Russian translation reading something in a diagonal direction (читать по диагонали) means reading quickly, without digging into it. I think proper English translation would be "to skim through".

It means in a cursory manner.

edit: funny to see all that we all replied at the same time. Just to add to the conversation, "diagonal reading" is not just a Russian idiom, it also exists in French :)

In German it's "querlesen" (read s.th. transversely, read s.th. across).

I guess Russian and French people start top left and stop bottom right, while Germans start top center and end bottom center ... (at least that's what I do).

In German we say „einen Text Überfliegen“ - fly over a Text. Funnily a „Überflieger“ is a person who excels at something, maybe with low effort.

Seems like a literal translation of Russian idiom meaning “skimmed through the text”.

I took it to mean "unofficially and as an outsider".

"Don't fry if you can't re-buy".

It seems necessary to point out here that if you fry your iOS device's circuitry experimenting with this stuff, when they capture the device to analyze what happened, you will likely end up paying for those repairs.

iOS is pretty stringent on power capacity coming through the wires. You'd have to make your own jailbreak tweak (or modify a current one) to fry your device with a cable

"Don't brick" doesn't have the same rhyme to it.

For example: Since there's a process for altering on-connector data, exercising that process could break a device in a way that disqualifies it for warranty repair.

I think to myself that DFU mode actually stands for "Don't F Up" rather than "Device Firmware Upgrade".

When I supported them I referred to it as “done f’d” instead, since it was typically used to recover from something gone wrong.

I fried the audio in my iPod Touch 2nd gen in high school trying to build an external battery charger. I took it back to BestBuy and just said it stopped working. He updated the software, checked the water damage marker, then gave me a new one.

Technically fraud...

> Many Lightning accessories I've played with have mirrored pinouts in their connectors

And some, like the “chimp” cables mentioned later, do actually care which direction you plug them in :)

Does anyone know what the black box is that he's connecting to in the picture? Is that the logic analyser or just some other accessory?

Could Apple come after this guy since he has access to leaked IP?

Even though he might have not done anything illegal, of course Apple might come after him.

Usually you can only go after the leaker or anyone republishing the IP. Simply having access to it isn't a crime. Perhaps they could issue some sort of takedown notice for the schematics.

Not a lawyer, but I seem to remember that trade secret law in California at least covers information you know should be secret. So if I'm remembering correctly, information derived from leaked docs would be subject to trade secret law.

IANAL also, but how would it play out in practice? Provisions in law are different to what can happen in practice. Perhaps enough damage has to be proven in order for remedy to be handed down?

And is it criminal violation, or just civil? And if civil, if the violation happens overseas, not much can be done in practice, right? I don't know much about American IP law.

This cable is clearly superior to USB-C. Why can't they make USB-C easier to plug in and reversible?

First of all, Apple was a contributing member to the USB-C group. [1]

Second of all, it is reversible (?)

It's inferior to USB-C in at least two ways:

1. The part that wears out is inside the phone in Lightning and inside the cable in USB-C

2. Lightning is for the most part USB 2.0 capable (though there is a newer USB 3.0 version - unsure how many devices/accessories support that).

[1] https://9to5mac.com/2015/03/14/apple-invent-usb-type-c/

Regarding your first point, it’s true that the part that wears out in Lightning is in the port, but on the flip side, the port of the USB-C is much more fragile (the internal “tongue” or whatever you want to call it is prone to breakage). There might be some hard data available on breakage rates, but anecdotally I’d say it’s really a wash in terms of durability.

However, where USB-C is really indisputably better than Lightning is that it has 3x the amount of pins (24 in USB-C vs 8 in Lightning), which will always mean that USB-C will be able to outperform Lightning significantly.

I'm curious to hear more on this. I have a number of USB-C devices and have never seen breakage on the internal port (only fluff buildup).

I had a Macbook where the power cord got stepped on, the cable head turned 45º or so and continued to function with no port damage whatsoever.

My wife broke the USB C port on my T470 when she threw a cushion at me (i was winding her up over something). It tore the connector shell off the board and lifted traces when the cushion landed fairly lightly on it after hitting me. Fortunately it has an old style charging port so I just use that. I didn’t use it for anything else.

But cheap USB-C connectors are crap. And USB-C connectors that are mounted on the motherboard of the device are a sin (Apple don’t do this - well done Apple!)

That really does seem like an implementation issue and not a connector standard issue. Connectors should at least be secured with through-hole pins for the casing IMHO.

They were on this machine. 4 through hole anchors. The shell deformed and ripped the other pins out. The issue is the mechanical leverage vs an 8 layer board vs connector sizing.

I've got a sad single port macbook on my desk here that has issues as the plug hole seems to have got wider and it doesn't make connections reliably with cables that plug into monitors.

I don’t know how it happened (never dropped it or yanked the cord hard or anything like that), but I’ve had the little USB-C tongue thing get a slightly bent downwards in the port which made it very difficult to plug in. I’ve seen a lot of other comments on the internet about how it breaks easily (it’s a common argument whenever this topic comes up on r/Android or r/Apple). I’ve never personally had a port fully break on me, but I could see it happening.

Anyone have long-run comparisons on fluff buildup? Hard to gauge changes in clothing / cases / etc I guess, unless you literally live with two phones.

I think Apple has its priority correct. We can make the pins inside iPhone extremely durable to the point when wear out happens you should be buying a new phone. Instead of having the tongue inside the Phone which could easily break the whole thing. So to me Lightning is still the better design.

Lightning can do USB 3.0 / 5Gbps, and I could see it possibly support 10Gbps with USB 3.2 2x1. But the problem is the first one operate at 2.5Ghz range which is known to course interference with WiFI and USB 3.2 is operating at close to 5Ghz.

I think on iPhone the problem may be bigger due to how closely packed they are. ( But I could be wrong )

> when wear out happens you should be buying a new phone

That may indeed by Apple's priority, but it's not mine.

Well my iPhone 6 lightning port is till working fine. That is closing to 6 years now. So I think Lightning Port is doing pretty well so far.

> the part that wears out is inside the phone in Lightning and inside the cable in USB-C

Can't speak to USB-C, but this is definitely a problem with lighting. I've had two phones usimply stop charging, presumably because the internal connector had worn out. Battery was fine, but there was no way to charge it.

Typically it’s not that the port dies but that it fills up with compacted lint to the point that the power pins can no longer make a connection. A careful pick around with a SIM tray tool usually revives it.

Right. If the tongue doesn't "snap" into position, but just mushes, the socket needs cleaning. You'll be amazed at the difference.

You can try with one of those dental picks that looks like a tiny pine tree. But, the last time I cleaned mine I needed a metal pick and a magnifying glass. That stuff really gets compacted. Be careful of the internal pins!

Same - I have an old simless phone that I use for banking and other sensitive apps. It only charges when the cable is just so.

Socket wear is definitely a design failure. Hoping it holds up until I end up replacing my current leaves-the-house phone.

I can pretty much guarantee that it’s not socket wear, but a buildup of lint/dust etc. I’ve got an original iPhone 5s whose lighting port still works perfectly. Needs to be cleaned out every now and then, but it’s durable as balls.

Thanks, but that's simply not the case.

The socket is clean, lint was the first thing I checked when it started happening. The uneven wear on the socket sheath is clearly visible under a magnifier. (This is a 6S.)

My biggest issue with Lightning is that it doesn't support HDMI over the cable. iPhones (and iPads) transmit an encoded stream to the Lighting to HDMI adapters which then gets decoded and converted to HDMI by a chip in the adapter. It adds encoding artifacts and latency.

And it also makes the adapter more expensive and fragile (they can overheat and kill themselves)

1. The part that wears out is inside the phone in Lightning and inside the cable in USB-C

Has this been a problem in practice? We should have enough data now (over 7 years since release) to know whether this is the case.

MiniUSB was horrible for this. The ports would lose the ability to grip cables and there was nothing to do other than replace the entire device.

[edited s/micro/mini]

Do you mean mini USB? Micro USB is supposed to be a big improvement in this department.

Yes, I did, sorry - typo on my part.

Samsung service centres swap out the usb socket. It's done in an hour.

Sure, but that assumes your phone is in warranty and your manufacturer will actually fix it in a reasonable amount of time. Even if they do, it's way easier to just replace the cable. The best option for a connector is for the easiest-to-break end to be on the component that's easiest/cheapest to replace.

Back in the day, vendors like Lenovo used to make the DC port easily swappable (separate daughterboard with modular cable to motherboard) because it was perhaps the most common simple wear part to fail. As a warranty tech I was doing this multiple times a day and it could be done in under ten minutes fairly easily. While the repair was of course free for warranty and service plan customers it was very inexpensive (relatively) for non-warranty customers, less than $50 if I recall correctly and that was due to a labor minimum, the part was only a few dollars as billed. Unfortunately even Lenovo has dropped this practice in the course of reducing case sizes and later switching to USB-C.

Of course this was also back when we made such a deal of turnaround time we used to call a taxi courier to deliver warranty units back to corporate customers with the higher end service plans. I'm not sure that you can get this kind of service any more with any vendor without using some small local VAR. I remember vehemently apologizing to electrical utility linemen that we didn't have a part in stock and so they wouldn't get their T50 back until we got the replacement in the next morning.

Perhaps part of this is compensated for by improved longevity in newer cables, but cycle life is rarely the problem (except perhaps on the iffier miniUSB), instead it's dropped/kicked/dragged devices. In general I am pretty frustrated with the decrease in serviceability of devices but this one is especially irritating, since like most people I've had a lot of devices where the charging port failed before everything else. USB-C feels like it represents a step back in a lot of ways because it's basically put the kibosh on magnetic charging interfaces (even more so than patents).

Anecdote, my iPhone has a busted lightning port after 2 years of fairly normal use. I wish I could just buy a new cable instead of needing to get my phone repaired, especially in the current health climate.

Clean out the port with a tiny pick - the ports probably not busted, just full of stuff.

In my experience this eventually happens to most iPhones. I know it doesn't fit with today's aesthetics but those older phones with rubber caps or sliding doors effectively prevented this issue.

My iPhone stopped charging after about 3 years, so it was definitely a problem for me.

n=1, but the feeling of ‘security’ of cables plugged into my MacBook Pro’s ports seems to have gradually decreased with time. Some are now even slightly position-dependent - I have to be very careful when copying files with some devices not to even slightly nudge the laptop.

This may of course be that the there is too great a variance in the design and manufacture of the male USB – C plugs leading to insecure connections… but either way, it’s worse than any other USB standard (even micro) I’ve used, and much worse than Lightning in this regard, in my experience

The 2020 MacBook Pro has changed that: theres a massive increase in friction/clickiness in the last mm of travel when plugging a cable in. Much more secure than my 2016

I had the 2016 MBP, bought just when it came out, and now the same (long story...), but built in 2020. The ports on the new one seem much more stable - one has to plug it in, and then on the last millimetre there is increased friction really holding it tight. I don't think the ports on my old machine had that feature, and yes, they were very fragile - I'd basically kick off the Time Machine backup on an external drive and leave the room, hoping that it finishes!

The ports on the new one seem more stable, though. Maybe they've iterated and improved it - think about how much time they had to optimise USB A.

This is good to know. You can get replacement USB-C boards[1] for the 2016/2017 MBP, and I've been wondering whether they have the improved ports that newer model years got, or whether the replacement board would wear out as quickly as the original board. Your experience suggests that maybe they're using better ports.

1. https://www.ifixit.com/Store/Mac/MacBook-Pro-Retina-A1706-A1...

For me, this was due to dust/lint build-up, and a 20 second fix. Not on a Macbook though. But generally my USB-C ports have never failed.


Mine too. The cables no longer clip in, and fall out without good resistance. This appears to be a problem unique to the MacBook though - the cables are fine and my other devices that should experience more wear on the ports are also fine.

I've slowly cycled through the good ports and I've only got one good one left now!

The 2016 and 2017 MacBook Pros are known for this problem -- supposedly it's fixed in newer models.

Same. If I have to use external media, I put my laptop on the table so I can keep things immobilized.

> 1. The part that wears out is inside the phone in Lightning

How is this mitigated in usb-c? As in how do they prevent the inside of usb-c from wearing out?

The friction pressure that keeps the cable in place is provided by the cable head, while the bit inside the computer is just a solid block with nothing that flexes. Rough handling can still damage the latter, but otherwise its expected lifespan is long enough to put in the 'don't bother worrying about it' column.

From what I've read, the USB-C cable does have a pair of springs (one on each side, pressing on slots on the sides of the "tongue"), so it's not just friction that keeps the cable in place.

Here's a picture illustrating this. Also note that the data contacts can fatigue as well!


The USB-C bit is more like a PCB with a shell around it. There's only a small amount of moving metal in the shell, reducing the amount of possible fatigue in the expensive part of the equation.

USB-C is sort of like "inverted lightning". The inside bit on the host looks very much like a lightning cable does.

They don't. The idea is that when it does wear out, replacing a cable is much easier than replacing a connector.

Right, my question was why doesn’t anything wear out in the usb-c female part of the connection. The answer apparently is that the usb-c cable holds the part of the connection that has moveable parts, whereas the lightning connector has the part that holds the cable in place in the device itself, so once that eventually wears out the cable has nothing to hold it in place.

> Why can't they make USB-C easier to plug in and reversible?

USB-C is reversible and easy to plug in:


Lightning does plugin easier.

I'm just imagining you with some sort of force meter analyzing exactly how much effort is required to plug in a cable.

they're both easy to the point where comparing is inane

it's not the force, it's the angle.

lightning is much better when you are plugging it in in the dark(for example).

That has not been my experience at all. I find it easier to plug in USB-C in the dark.

Yeah, it’s also more round, which helps guide the connector, whereas usb is a perfect 90 degrees/perpendicular to the case or wherever

Connector specifications literally do specify insertion and removal force in e.g. Newtons, as well as how many times they should withstand unplugging/reconnecting, etc.

They(Apple) designed both. They gave the worse one to the public. I wish they had the forethought to realize that usb-c would become ubiquitous, and people would be calling for it to replace lightning. Now it’s just too late. They will need to eventually adopt the worse connector just bec it will make sense internally for all Apple devices to use the same charger.

Usbc is too big for certain applications. Also, usbc wasn’t out yet

USBc is not too big for phones. Lots of phones use USBc now. It's only too big for Apple phones, because Apple will never think their phones are thin enough until you can see through them.

iPhones have been getting thicker since 2014.

Apple TV remote Pencil

exactly...(was an engineer at Apple before and after lightning came out

Are you perhaps referring to mini USB? USB-C is already reversible.

Is this a joke? USB-C is reversible.

We'll probably never see USB-C from Apple because of the intense effort that went into the NIH Syndrome to come up with this connector

Well the alternative at the time was USB 3 Micro B. If you haven’t seen that connector then I suggest you google it for a laugh.

Personally I’m glad Apple picked a robust, reversible connector and stuck with it.

USB 3 Micro B was always funny to me. It's backwards compatible with USB 2 Micro connectors, so in theory it's a nice upgrade path at the time. In practice, though, it's often used for USB HDDs, and often those drives couldn't function reliably with the power levels of a USB 2 connection, so using them with a USB 2 micro connector was not only much slower, but they'd just power down randomly.

I like lightning connector, but it too has it's silly hacks. The HDMI dongles are an amazing level of silliness, down to a slimmed down iOS image being copied to the dongle and run there to enable a h264 decoder to run on the dongle itself. It works, kinda sorta.

Wait, really? Do you have more information on the HDMI dongle? I'd read a whole novel about that.

This twitter thread has more details: https://threadreaderapp.com/thread/1155148789977636864.html

There's been some discussion here on HN: https://news.ycombinator.com/item?id=20554462

Here's a starting point - I recall seeing someone debugging the iOS boot on the dongle but can't find that info right now



This is strange because... one of the big complaints about Apple's Mac computers is they only have USB-C. They ship Macs and iPads with USB-C.

Apple was also a significant contributing member to the USB-C spec/working group.

All of Apple's current desktop Macs have several USB-A ports as well.

Weird, I'm not sure why so many people think an overuse of USB-C on Apple's computers disproves your accusation of NIH Syndrome for iPhones/iPads. To the point of downvoting you, even!

> I’m not sure why so many people think an overuse of USB-C on Apple’s computers […]

The point is GP stated any use would be unlike Apple. I quote: “We'll probably never see USB-C from Apple”.

That’s what people are downvoting, a plainly disapproval assertion.

Your ‘overuse’ crack doesn’t jibe well with the suggestion of NIH syndrome; USB-C is an industry standard and all vendors should be and are adopting it. Lightning was invented before USB-C and solved issues that standards of the day (2010), including the various USB connectors, did not for another 5 to 6 years.

HN users have a tendency to downvote things that are easily unproven.

> GP stated any use would be unlike Apple

The context is the stuff that uses lightning. Taking it so literally, to the point of downvoting, is definitely not in the spirit of "strongest plausible interpretation".

So, sure, the ipad pro has USB-C, and that's worth pointing out as a minor note. But the reason iPhone doesn't use it is in very large part a combination of stubbornness from being first and NIH.

> Your ‘overuse’ crack doesn’t jibe well with the suggestion of NIH syndrome; USB-C is an industry standard and all vendors should be and are adopting it.

All laptops should have multiple USB-C ports. But getting rid of every single type A port is putting too much emphasis on C.

> Lightning was invented before USB-C and solved issues that standards of the day (2010), including the various USB connectors, did not for another 5 to 6 years.

Are you comparing the invention date of lightning to the widespread adoption of USB-C? Because USB-C was announced in 2013 and almost certainly qualifies as 'invented' in 2012 if not earlier. And there were devices sporting it in 2014, only two years after lightning devices.

> The context is the stuff that uses lightning.

So the iPad Pro's USB-C port in its current and previous generations immediately refutes GP.

> Taking it so literally, to the point of downvoting, is definitely not in the spirit of "strongest plausible interpretation".

Discussion about down votes is also in contradiction with the HN guidelines. I prefer we didn't start quoting the guidelines, though; that only detracts further.

Making an assertion in contradiction with the truth isn’t an opinion, it’s just flat out false. People can react how best they see fit, and some have chosen to downvote, possibly because they think a false assertion doesn’t meaningfully contribute; others like me prefer to leave a comment.

But complaining about downvotes isn’t a useful contribution either. I just felt, again, like commenting.

Point is GP was wrong. Value judgements about how many ports Apple puts in its laptops is entirely superfluous to that point.

> So the iPad Pro's USB-C port in its current and previous generations immediately refutes GP.

In my experience many of the people who have an eternally tight clutch on their pearls where Apple is concerned barely actually know anything about the company's product lineup.

> So the iPad Pro's USB-C port

Just gonna ignore that I already addressed that?

Yeah, there is one exception in the product stack after many years.

But they're still sticking super hard to lightning, making everything more complicated than it needs to be.

> But complaining about downvotes isn’t a useful contribution either. I just felt, again, like commenting.

That was just an afterthought in my post, to show how extremely people were interpreting the post, despite there being a very valid point if you read it at 80% intensity instead of 100% intensity. The point of my post was valid discussion of Apple.

Well, the ipad pro and some MacBooks have USB Type C...

All MacBooks have USB-C, and have for nearly 5 years.

The mac I'm typing this on doesn't just have USB-C, it only has USB-C.

The entire MacBook line and the iPad Pro would like a word with you.

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