Are certificates usually/often issued to expire at the end of a given calendar year? On the one hand, that would explain this happening on Dec 31.

But it's slightly weird because it's not yet the new year in UTC. This was posted several hours before that happening, and we've still got over 2 hours to go... (And the cinema is in New York, with almost 8 hours to go in local time, so it's not a local timezone issue either.)

This is Sony, and it is the new year in Japan.

Sony is a Japanese company but it's also a multinational company consisting of hundreds of companies they aquired over the years all over the globe. It's therefore a relatively small chance is has something to do with Japan specifically.

It likely depends on where the programmer who has the original cert issued was... so quite likely Japan, given the evidence

This is the most likely, yup. The certs are unlikely to have a precise end-of-year expiration. It will be whatever the expiration is for the last certs loaded.

10 years in cinema IoT, here. Features are encrypted by Key Delivery Messages (KDM), and those are per cinema server/projector "marriage". No KDM will be considered valid if the server certs are expired.

This should make 2024 interesting for me.

(fyi)Japan Standard Time(JST) is UTC+9, single zone and no DST. Not sure of absolute time but Tweet is showing "Jan 1, 2024 at 2:19" timestamp on my JST phone.

The Dolby/Doremi servers certificate ended the Dec 31 too. Our maintenance subcontractor updated them few weeks ago. SO I guess it is common for the industry. Then it is an industry which often play 365d/year so, it's just another sunday/monday. (Add to this our weeks doesn't start Sunday/Monday, but Wednesday for France by example, and Friday for the US, day of the release of new movies)

A digital cinema tech with the username "sprocket35"?

I mean his comment history is on par with who he says he is - I think it's a great name. Just because I work mostly in the digital domain doesn't mean I dont long for the analog.

There have been stranger things

Honestly, is that better? Leaving all the devices set to EOL and get bricked or whatever feels pretty wasteful.

The studios set the requirements. A certificate that never expires would never fly with their need to control DRM as tightly as possible.

If Sony was still in the business, they would offer a certificate renewal for a small fee like the other manufacturers have done.

The root problem is that Sony exited the market and left a lot of cinema owners out to dry with the looming cost of $50,000+ per auditorium for replacement projectors.

IMHO a certificate that expires at the same time as the copyright on a film, and DRM that then "fails open", makes the most sense.

Okay, then I set the date on my computer to year the 2124. Now the DRM is unlocked!

You can't build a "time lock" with just encryption primitives. Even if you could build a time lock with just encryption primitives, we don't know when the copyright will expire until the original author has died, since copyright term is life + 70 years.

Someone would have to run a server that specifically chooses to start serving the keys on that date, which is an absurd notion given how absurdly long copyright lasts these days.

If the federal government were interested in passing a law that required this, I'm sure the Library of Congress could run such a server, but no such law exists.

Not at all absurd.

Maybe not through crypto but otherwise perfectly achievable. No reason to achieve this within a file. If you really want to, some fancy solution involving blockchains and smart contracts is probably possible but there is no need.

Require by law all who desire copyright protection to register the work with a governmental agency and place a copy of the work in escrow at an archive as a condition. The archive knows when the copyright expires and starts serving the work to the public from that point forward. This is what to do if a state cares about public domain.

The status quo of corporations abandoning works to bit rot, actual rot, misplacement or fires for decades is strictly worse.

>> If the federal government were interested in passing a law that required this, I'm sure the Library of Congress could run such a server, but no such law exists.

> Require by law all who desire copyright protection to register the work with a governmental agency and place a copy of the work in escrow at an archive as a condition.

You’re just repeating what I already wrote. By all means, call your representatives.

> set the date on my computer to year the 2124. Now the DRM is unlocked!

It's the same. "Fail closed" means you can "just" set the system time to be before the expiration date, "fail open" means you can just set the system time to be after.

Either way, having an expiring decryption key is just security theater that harms users.

I imagine most systems needing a trusted clock do so with a positive GPS lock.

Spoofing that now gets you in trouble with the FCC as well as the DMCA.

No need to spoof the GPS signal, pop open the lid and replace the GPS chip with one that outputs an attacker-controlled time signal. I suppose it could encrypt this signal with some certificate burned into the silicon, but that could still (slowly and painfully) be reverse-engineered.

GP’s point stands, you can’t enforce a time lock with cryptography primitives. That’s the fundamental issue with DRM - you’re trying to restrict someone from getting your ciphertext, while at the same time allowing them to get to it if they meet certain (non-cryptographic) conditions, which standard cryptography just can’t do.

Not for the studios. There’s nothing more they would love than to get a continuous and non-ending stream of money for content they themselves have forgotten about owning.

There hasn't been cryptographic algorithms nor a DRM that proved good for > 50 years, let alone 70 years + safety margin. Even 3650 days expiry is considered too long.

> The root problem is that Sony exited the market and left a lot of cinema owners out to dry with the looming cost of $50,000+ per auditorium for replacement projectors.

That's the point I was trying to make; if someone accidentally pushed a broken update, that sucks, but its not the first or the last time it will happen, and at least there's a clear path to it getting fixed and someone being paid to do it. The cert being expired and the only company who would have been in charge of fixing that not really caring anymore sounds to me worse from pretty much any possible point of view, and selling a product that will stop working if you decide to stop servicing it seems pretty terrible.

And yet, many of the products we buy are exactly that. Gaming consoles dependant on online stores, smart TVs with software that could become useless at any moment, hundreds of little iot devices that are dependent on the manufacturers cloud being online... The list goes on.

This kind of thing is all over the consumer world. In a way it's cathartic to see it hitting businesses too.

Any idea if these projectors could be made to work with other sources that don't require DRM? As much as this sucks for movie theaters, it could also be the deal of the century for a home theater build if you know the right people...

I don't think you'd want to pay the power bill for one, nor would you want to have a large enough screen to not have it burn your retinas. That said I believe some of them do allow that (no clue what models or availability) since you can rent out theaters to play games on your own computer or console, https://www.cinemark.com/private-events/gaming/

If you’re in Central Texas, one of my high school friends and her husband run The Beltonian in Belton (shocking), a beautiful single-screen theatre built in 1922, renovated to have about 140 modern seats with tables, featuring various classic movies, reasonably-priced pub grub, Central Texas wines and beers, and available for similar rental arrangements (gaming or movies).

If you’re not in Central Texas, you likely have a similar, beautifully-restored old theatre available for similar rental arrangements.

The Beltonian: https://thebeltoniantheatre.com/

Sure, maybe you wouldn't want it for a personal movie screen, since it's massive overkill for home use, but... you could definitely get use out of it for projection mapping your home and have the most amazing holiday displays on the block.

Having a short term cert seems wasteful too.

How frequently does Sony change its identity. They should have a 999 year cert expiration and then check a revocation list in the off chance they Sony gets its private keys rooted.

I don't disagree! I don't feel like the exact technical justification really makes a difference here; there were working projectors, and now there aren't, and it's hard to see how that's not directly due to Sony designing things in a way that required them to continue operating that part of the business in order for that not to happen.

I agree but you do need to bear in mind that this isn’t a uniquely Sony design. Sadly, this is the mindset of the movie industry as a whole.

That needs to change before any trickle down effect to projector hardware can happen. But there’s no incentive for studios to change the way they given their IP because they benefit from the status quo

I'm surprised they even allow a certificate greater than 13 months /s

Any insight as to why they exited the movie projector business? I am also pretty sure they will honour any maintain contract?

They left because their liquid crystal panels suffered from chronic burn-in and the cost of replacing them was no longer economically feasible. It was tolerable when “virtual print fees” were subsidizing the transition from 35mm film to digital but now that era is over and movie theaters owners are smart enough to buy DLP projectors which don’t suffer from the burn in problem.