The Joy of Cryptography • Hacker News Board

Re: The Joy of Cryptography

#101

Post by garmaine » Sun, Nov 28, 2021, 10:12 AM UTC

marcan_42 wrote: post #98

upofadown wrote: post #97

Earlier quoted context omitted.

If you want to prove that ed25519 is generally faster than RSA for signatures I think you would have to find a benchmark that supports your contention.

https://blog.cloudflare.com/ecdsa-the-digital-signature-algo... RSA 2048 bits: 1001 signatures per second ECDSA P-256: 9516 signatures per second Note that 256-bit RSA provides a higher security level than 2048-bit RSA, so this is biased in RSA's favor. https://connect2id.com/blog/nimbus-jose-jwt-6 That one has ed25519 signing 60x faster than RSA-2048. Verification is a bit slower with ed25519 (RSA is very asymmetric…

I wouldn’t waste your time. He appears to be trolling.

Re: The Joy of Cryptography

#102

Post by clint » Mon, Nov 29, 2021, 6:10 PM UTC

1cvmask wrote: post #3

This is the coolest way I have seen someone write their email and avoid email harvesting bots: For inquiries related to this book, use x@joyofcryptography.com, where x is the author's first name. - Nearly everyone with a high school education can “crack” that puzzle and figure out his email and yet most bots will fail.

Its a very old technique from the 90s actually!

Re: The Joy of Cryptography

#103

Post by bdamm » Tue, Nov 30, 2021, 6:00 PM UTC

Terry_Roll wrote: post #100

bdamm wrote: post #87

Earlier quoted context omitted.

Cryptanalysis is a pretty robust area of research. There are in fact a lot of cryptanalysts that know CPUs quite deeply. Certain organizations spend a great deal of money to make it so. If vulnerabilities are found we learn from them and advance the understanding of cryptography design. It has been that way for 76 years now, at least.

Not disputing what you say, but mistakes do happen to the best of us. http://sunnyday.mit.edu/accidents/Ariane5accidentreport.html and yet again another OpenSSL bug , another flaw in the open source fallacy of many eyes to spot bugs... https://nakedsecurity.sophos.com/2021/03/28/serious-security... plus when considering in maths there are ways to rearrange formulas including new discoveries like this one (a new way t…

You won't be the first, or the last, to wonder this. There are people who have dedicated entire lives to it.

Look into post quantum cryptography if you're interested to know about one of the big trains heading our way.

Re: The Joy of Cryptography

#104

Post by Terry_Roll » Thu, Dec 02, 2021, 2:44 AM UTC

bdamm wrote: post #103

Terry_Roll wrote: post #100

Earlier quoted context omitted.

Not disputing what you say, but mistakes do happen to the best of us. http://sunnyday.mit.edu/accidents/Ariane5accidentreport.html and yet again another OpenSSL bug , another flaw in the open source fallacy of many eyes to spot bugs... https://nakedsecurity.sophos.com/2021/03/28/serious-security... plus when considering in maths there are ways to rearrange formulas including new discoveries like this one (a new way t…

You won't be the first, or the last, to wonder this. There are people who have dedicated entire lives to it. Look into post quantum cryptography if you're interested to know about one of the big trains heading our way.

So using the basic definition of quantum computing being "a device which can compute all permutations at once", in theory yes it is a 0x73 0x68 0x69 0x74 0x20 0x73 0x74 0x6f 0x72 0x6d but thats because these algo's do not encompass time and a place.

Build time into an algo and then you need a quantum computer which can also roll back or forward time.

You see the problem is, how do you build time into an algorithm like a particle decay? And if you could, could you then make it like a time delayed bank vault which only opens for certain windows during the course of the particle decay?

I also wonder if a place, some co-ordinates could also be built into an algo if that is even possible. There are medieval examples, namely trusted couriers but then you are not looking so much at an algo but more a self contained device to defeat quantum computing.

Anyway for now, you've got the NSA data centre at Bluffdale Utah which can sort of replicate quantum computing by running multiple instances with each using one pwd from all the possible pwd combination to look for the magic bytes in a file https://en.wikipedia.org/wiki/List_of_file_signatures in order to decrypt files. A variation of that Could be used for replay attacks on network communication.

At least thats how I would do it quickly and easily.

Re: The Joy of Cryptography

#105

Post by bdamm » Sat, Dec 04, 2021, 5:23 AM UTC

Terry_Roll wrote: post #104

bdamm wrote: post #103

Earlier quoted context omitted.

You won't be the first, or the last, to wonder this. There are people who have dedicated entire lives to it. Look into post quantum cryptography if you're interested to know about one of the big trains heading our way.

So using the basic definition of quantum computing being "a device which can compute all permutations at once", in theory yes it is a 0x73 0x68 0x69 0x74 0x20 0x73 0x74 0x6f 0x72 0x6d but thats because these algo's do not encompass time and a place. Build time into an algo and then you need a quantum computer which can also roll back or forward time. You see the problem is, how do you build time into an algorithm lik…

That’s not how quantum computers work, but you’re on the right track. And yes, time is almost always an essential part of crypto algorithms (usually proving the order of things, e.g. when using nonces, or temporary keys to block re-generation as with ephemeral keys.)