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Re:FreeBSD 13.0 Beta1 Now Available by jiggawatts on Saturday February 06, 2021 @07:58PM (#26051666)
One thing I haven't quite understood is why Netflix even bothers to encrypt the video streams. It seems like a waste of effort, since Netflix isn't exactly serving content that would qualify as "secret". There's not even any porn on there, so it's not the biggest concern if someone were to find out what some people were watching. This data is being collected anyway via endpoint technologies like Samsung's Automated Content Recognition (ACR): https://www.samsung.com/us/business/samsungads/resources/tv-...

It seems like encrypting the video stream traffic at this kind of scale requires a substantial engineering effort and special hardware.

Encryption also means that shared downstream caches at ISPs can't do anything to reduce their bandwidth consumption. The only option is to contact Netflix and physically install one of their edge caching boxes.

Content tampering protection could be obtained by simply computing content hashes offline once, which the clients could verify.

Re:FreeBSD 13.0 Beta1 Now Available by throwawayboise on Saturday February 06, 2021 @10:04PM (#26052269)
> There's not even any porn on there, so it's not the biggest concern if someone were to find out what some people were watching.

True there's no out-and-out porn, but there is content that's close to the line, and beyond that there are themes that could be indicators that a viewer is gay, or in some other demographic that he might want to keep private.

Target can tell if you're pregnant based on your shopping; certainly there's a lot that can be inferred from the movies you watch.

Re:FreeBSD 13.0 Beta1 Now Available by the-dude on Sunday February 07, 2021 @05:40AM (#26054065)
> Target can tell if you're pregnant based on your shopping;

I am very skeptical about that story, it sounds too good/scary to be true, and there is only 1 reported incident, without proper sources. Sounds made up to me.

https://medium.com/@colin.fraser/target-didnt-figure-out-a-t...

Re:FreeBSD 13.0 Beta1 Now Available by drewg123 on Saturday February 06, 2021 @08:27PM (#26051790)
"This helps protect member privacy, particularly when the network is insecure — ensuring that our members are safe from eavesdropping by anyone who might want to record their viewing habits." from https://netflixtechblog.com/protecting-netflix-viewing-priva...
Re:FreeBSD 13.0 Beta1 Now Available by fis on Saturday February 06, 2021 @09:23PM (#26052065)
The parent mentioned "This data is being collected anyway via endpoint technologies like Samsung's Automated Content Recognition (ACR)". If that's true then the encryption isn't really helping.
Re:FreeBSD 13.0 Beta1 Now Available by dagenix on Saturday February 06, 2021 @09:58PM (#26052237)
What if you aren't using a Samsung device?
Re:FreeBSD 13.0 Beta1 Now Available by paulmd on Sunday February 07, 2021 @01:43AM (#26053184)
Samsung was one of the companies caught using their apps to scrape data out of the filesystem (config files and logs from other apps, location from camera roll, etc) and using it to bypass permissions you didn't want to give them.

https://www.xda-developers.com/android-permissions-bypass-pl...

https://www.trustedreviews.com/news/facebook-scraping-call-m...

They are completely terrible on privacy, lol, the answer here is "if you care about privacy don't use a samsung". Or more generally "don't use android".

Re:FreeBSD 13.0 Beta1 Now Available by dagenix on Sunday February 07, 2021 @03:08AM (#26053474)
I'm not really sure what you are getting at. Regardless of what Samsung is doing, I'm confused by the argument that encryption is useless because Samsung might take steps to work around it when not using a Samsung device is a viable option.
Re:FreeBSD 13.0 Beta1 Now Available by paulmd on Wednesday February 10, 2021 @04:26AM (#26087137)
Samsung has below-root-level access on their phones, their apps are fundamentally aggressive towards your privacy (as repeatedly demonstrated in practice) and impossible to dig out without a complete image replacement. Maybe not even then.

If you care about privacy, you don't buy Samsung phones (or other products like TVs). They are the tip of the spear on data collection.

Re:FreeBSD 13.0 Beta1 Now Available by Macha on Sunday February 07, 2021 @07:51AM (#26054671)
They're required to let you choose whether to opt in to ACR in Europe because of the GDPR. While the prompt is terribly vague and designed to encourage "just hit yes" behaviour, I have a q60r and the setup wizard at least presented a prompt I could opt out of.

Also while HN likes to raise the spectre of TVs connecting to open wifi/shipping with 5G radios, at the moment there is no evidence for either so users could always use a trusted device to play back Netflix rather than the TV app and leave the TV without internet

Re:FreeBSD 13.0 Beta1 Now Available by cperciva on Saturday February 06, 2021 @09:20PM (#26052050)
Come on Drew, you know as well as I do that media can be unmasked via side channels if an attacker really cares.
Re:FreeBSD 13.0 Beta1 Now Available by geofft on Saturday February 06, 2021 @10:43PM (#26052458)
Is this actually in reach for realistic attackers?

Like let's say you're a network admin of a college with conservative religious views, and you want to see if anyone in the dorms is watching "immoral" content. You probably can just intercept an entire unencrypted session and replay it on your machine and see what it was. But you don't really have the funding or access to expertise to develop a side channel attack yourself, and there are no off-the-shelf devices that will do this for you, are there?

Encryption is likely the difference between your management saying "Show me what the kids are watching" and "This isn't worth assigning our network admin to spend half a year on effectively a cryptography research problem."

(Incidentally, encryption may also be what allows a sympathetic network admin to refuse an order from their management, which is also worth considering in your threat model.)

I think it's true that if you had either the resources of one of the richest handful of countries in the world or access to some talented grad students etc., you could do it. But if you're even a non-rich country (like one of the many small countries with moralistic governments that censor the internet) it seems harder, and if the goal is spying on what people watch, it's unlikely that people talented enough to do it will find this a problem they're happy to volunteer their time to solve.

(This is a genuine question - the attack might be much easier than I think!)

Re:FreeBSD 13.0 Beta1 Now Available by jabberwcky on Saturday February 06, 2021 @10:03PM (#26052261)
Are you attacking him because he's using TLS? Will you ever be satisfied?

TLS fixes a whole lot more than just privacy, it's also authenticating the remote end. Are we really suggesting dumping something that is trivially accelerated in hardware to do some homebrew crypto crap just for the sake of a forum thread?

Netflix solution is fine, and the concentration of interest in TLS means it only gets cheaper over time to build Netflix-like configurations, which is especially great since we've spent the past decade or more trying to convince the entire industry this configuration is also best practice

Re:FreeBSD 13.0 Beta1 Now Available by cperciva on Saturday February 06, 2021 @10:08PM (#26052290)
I'm just pointing out that the privacy justification is nonsense. Protecting the integrity of connections? That's important. Preventing web browsers from throwing a fit about "insecure connections"? That's also important. But privacy isn't the issue here, and I've talked to enough people at Netflix to know that they know that too.
Re:FreeBSD 13.0 Beta1 Now Available by bobthebuilders on Sunday February 07, 2021 @01:13AM (#26053073)
Most people can download a program that sniffs HTTP. Using side channels is not a simple affair.
Re:FreeBSD 13.0 Beta1 Now Available by yjftsjthsd-h on Saturday February 06, 2021 @09:43PM (#26052167)
Maybe, but why make it easy?
Re:FreeBSD 13.0 Beta1 Now Available by kstrauser on Saturday February 06, 2021 @10:22PM (#26052352)
People, before you downvote, check out the username.

But yeah, you’re right. You could glean a lot of information from nothing but a collection of movies’ exact runtimes, as visible from the network stream. Although that wouldn’t tell you much about a single movie, given enough viewings you could make pretty good guesses about which movies someone is watching.

Re:FreeBSD 13.0 Beta1 Now Available by dagenix on Sunday February 07, 2021 @03:18AM (#26053525)
It doesn't matter who said it. What matters is that they are wrong. Encrypting the connection significantly complicates that attack.
Re:FreeBSD 13.0 Beta1 Now Available by stock_toaster on Saturday February 06, 2021 @08:20PM (#26051761)
My guess would be to prevent middlebox fiddling.

Such as an end user device asking for 4k, but a middlebox somewhere between the customer and Netflix inspecting the http content and blocking it (or modifying the client request in flight), because "only 480p allowed here" or something like that.

Re:FreeBSD 13.0 Beta1 Now Available by mrpippy on Sunday February 07, 2021 @12:58AM (#26053012)
US cellular carriers do that by throttling bandwidth to the network ranges used by video providers
Re:FreeBSD 13.0 Beta1 Now Available by toast0 on Saturday February 06, 2021 @08:27PM (#26051791)
Who's watching what is secret data and although it can be possible to extract that from packet sizes and duration of streaming, it's a lot easier to extract it from http paths.

But, beyond that, the battle to use http when it makes sense has been lost. Modern platforms strongly encourage https and discourage http.

Re:FreeBSD 13.0 Beta1 Now Available by jen20 on Saturday February 06, 2021 @08:24PM (#26051778)
I'd imagine the poor behaviour of ISPs (especially in the US) with regards to privacy is the reason. Deriving reported speeds for `fast.com` from the video sources was a masterstroke, too!
Re:FreeBSD 13.0 Beta1 Now Available by ikawe on Saturday February 06, 2021 @08:29PM (#26051804)
Sure, things like ACR exist, it doesn't mean we should give up. Lots of people think "privacy mode" should be default for everything and isn't just for when you're watching porn.
Re:FreeBSD 13.0 Beta1 Now Available by freedomben on Saturday February 06, 2021 @08:01PM (#26051686)
I would guess it's for DRM.
Re:FreeBSD 13.0 Beta1 Now Available by paulgdp on Saturday February 06, 2021 @08:12PM (#26051725)
Encryption for DRM needs to happen only once per media, and then can be saved to storage and shared infinitely many times. So that's probably something else