contrarian_

"linear transformations with soft thresholds sandwiched in between"

Investment in mining hardware whose value is tied to a speculative asset without fundamental value beyond utility.

None of the current implementations can scale, so even their utility is questionable. There is a way to make a scalable trust-less digital currency by using a mutable leder, but none of the current coins that I know of are heading that way. The main difficulty will be how to distribute ledger space in a way that cannot be monopolized by the richest. That is a simple technical problem to solve though, because storage capacity will eventually surpass the ratio of richest to average wealth. Then you can allocate ledger space in exchange for an affordable deposit, redeemable when the balance is emptied.

It's a winner-takes-all market, so there are absolutely strong economic incentives to build the best robovacuum control software.

> Play Store inherently allows for competition

Really?

https://play.google.com/intl/en_us/about/developer-distribut...

> (4.5) Alternative Stores. You may not use Google Play to distribute or make available any Product which has a purpose that facilitates the distribution of software applications and games for use on Android devices outside of Google Play.

You have no chance of bootstrapping an alternative store outside of Google Play. Sideloading APKs is not how users get software on Android. Amazon failed hard with their attempt, and they pumped tons of money into it by paying developers to give away their apps for free; that, and they shipped hardware that has their store preloaded. Still didn't even make a dent.

> Mining new bitcoins makes transaction easier

No. As long as at least one person is brute forcing hashes, transactions will be processed at the same rate of about 10 tx/s.

Sure you might not like SAP's business practices but there are very few large software companies in Europe.

How do you suggest writing a thin API layer to expose an interactive real-time stream consumed over WebSocket?

> The idea would be that you want sellers to pay something to participate in the market

What? Why would you want to do that beyond covering expenses for scam prevention?

The network connection side panel also seems to never open when you want it to, only to open 2 minutes later when you are watching a fullscreen video.

The toy example referenced in section 6.4 is actually closer to Spectre. It's missing the crucial distinction that the speculatively loaded address should belong to a page inaccessible from the current ring level.

To see why that toy example is insufficient, consider that you could simply execute the load directly without putting an exception in front of it and you would be able to read the value.

AMD CPUs are completely unaffected by Meltdown, since AMD checks permissions before fetching memory into the cache.

Emphasis on "mitigate".

WRONG. You fell for the Intel PR strategy. AMD is completely unaffected by Meltdown, since AMD checks permissions before fetching memory into the cache.

Much more leeway for "unintended cheating" with 2D signals. Think of all the imperceptible patterns that could be used as distinguishers. ML methods basically search for these shortcuts.

Same can be said of CryCash: https://crycash.io/

CryTek was on the verge of bankruptcy a year ago when they were unable to pay their employees. The one-time payment from Amazon in exchange for the engine distribution rights is probably running out.

https://www.reddit.com/r/gamedev/comments/7l640w/crytek_has_...

https://www.reddit.com/r/gamedev/comments/5wzlf2/crytek_empl...

http://www.eurogamer.net/articles/2016-12-20-crytek-breaks-s...

Bitcoin crashes at least as hard as the economy in times of downturn. Probably harder.

ELI5 why is the multiple patterning not additive in the same way as interference?

Yep, I was actually debating whether I'd mention sendmmsg/recvmmsg in my original post but I left it out. Definitely an option for UDP, but you're out of luck if your game server uses TCP (surprisingly many do) because you have to recv from each socket separately.

No no no, you can easily train the branch predictor by sending a bunch of valid requests followed by an invalid request with a payload that redirects the ensuing speculative load into your desired address range.

> artificial neurons

Differentiable functions

Intel's L3 cache is inclusive. Spectre most definitely also applies across different cores.

Pretty much what I predicted here: https://news.ycombinator.com/item?id=16054674

> Sounds like servers handling lots of small UDP packets would be hit pretty hard.

> The solution may lie in a new "non-speculative load“ instruction that delays execution until preceding branches are confirmed.

That's sadly not enough.

There are also potential speculation-based side-channels that are unrelated to cache: timing the idiv operation whose latency "depends on number of significant bits in absolute value of dividend." Furthermore there are many ways to measure contention on the execution ports which can leak information about the speculative execution.

Huh, so did Intel know about this vulnerability when they designed SGX?

You can then detect which addresses were loaded because they caused other cache lines to be evicted.

Even if speculative loads do not modify the cache, you could still have a side channel by analyzing the memory bus contention.

IMO there is no way to get rid of these timing attacks entirely without getting rid of SMT and speculation.

2006: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.190...

From the abstract:

> Information leakage through covert channels and side channels is becoming a serious problem, especially when these are enhanced by modern processor architecture features. We show how processor architecture features such as simultaneous multithreading, control speculation and shared caches can inadvertently accelerate such covert channels or enable new covert channels and side channels.

No, you could also find a gadget with ROP techniques. The eBPF thing in the paper was purely due to convenience of exploitation.

Too bad arbitrary real numbers cannot be represented in finite memory.

Yet another case where running an Anti-Virus makes your system less secure.