Listen up faggots

hey Veeky Forums im a software engineer at a bank/credit card company and I just came back from our internal software engineering conference and they mentioned that blockchain engineers are being sought out after with offers above 2X the rate of a regular engineer.

there's just such a large amount benefits that can be harnessed using blockchain tech that it would eliminate clearing houses and lots of third party verification needed for payments.

take this advice as you will, I'm going to go do some research and see if I can learn all there is to know about using blockchains outside of memecoins.

This is interesting. I'm a CS student, looking to graduate a year from now. How do I get into this?

what I go out of the presentations was simple, learn it so well that you can make your own coin and find a simple, real world example and try implementing it.

What do you mean by real world example? Implementing a coin that solves some real world problem?

exactly. the example that I was given was "let's say you need to hire a nanny, and when she got her CPR certification she got a QR code that will show that in the (public) ledger that this person does in fact have a CPR license without having to wonder if the documentation is real or not"

How would your example work? We still need some authority to grant that cert. So that authority would sign a transaction in the block chain that certifies her cert? Would she need to have a stake in the block chain as well?

Just some thoughts, I'm still a noob about block chain tech.

The QR code would just contain a signature, signed by some private key only the issuing authority of those documents would have access to. This prevents counterfeiting and alteration, but not copying.

the simplest way of explaining it is that when the nanny goes to get their CPR training, their information get added to this public ledger maintained by some authority like the red cross. They give you a QR, which might just be a key to find their entry in this public ledger.

>clearly never used public key cryptography
No. All the Red Cross has to do is provide a public key. They own and solely have access to the corresponding private key. They can sign any message with their private key, and everyone else can verify that this exact message was signed by the privkey using the pubkey.

Basically the system you just described made all records completely public, and basically added no advantage over the current system of... well, maintaining long ass lists of people and trying our best to not get that information stolen. Here things can be verified without an Internet connection, without asking some authority. A computer can tell you on its own whether or not this message was signed by a party.

you're right. the thing is that this is a basic example of how it can change document verification procedures.

>doesn't prevent copying
so it's useless?

you can photocopy documents and they do not lose their validity if they are immutable due to the ledger.

what if it gets copied by someone against my wishes?

what they will copy will just be a hash then, nothing usable with a key. similar to PGP encryption but with the speed of the ledger for storing this data.

without a key*** woops.

this guy is right, you clearly know nothing about public key cryptography or PKI

i seriously hope you just misunderstood the example, because a bank should really be on top of this shit

>so it's useless?
Absolutely not. Here is an example.

I sign a message saying "hello world" with my private key. Ideally, everyone else in the world has a copy of my public key. This is not reality, but the way we do this is with keyservers. So each key has a fingerprint, and when you get a message encrypted with a key you have not seen before, you can ideally get it from the Internet. "Hey, MIT, I got a message signed with 4AEDD4. You have that public key on your server?" "Yeah. Here."

Now I have the public key with fingerprint 4AEDD4. In reality these fingerprints are a bit longer but its just for example. Now I have a message, which includes the text someone typed (or it could be a file) and then a long hash called a signature. It's a bunch of letters. I verify, check against, the public key I have. This is a bunch of complicated maths but once you see how it works, it makes more sense. The computer tells me, yes, this message was signed by the owner of 4AEDD4 on May 25, 2016 at 10:41AM. Now I alter the message that was signed with this big signature, changing it from "hello world" to "fuck you." Nope, doesn't verify. Right? So this is a lot like how websites store your password. When you submit it, your password "cocksrock" isn't sent in any form to the website (usually). They'll hash it. "cocksrock" hashed with MD5 algorithm is e1ae997bfa0dd7577f0cf34e12a672c9. That's what the website stores. So you have no way of finding out what that hash means working backwards. You could never CALCULATE that it is the MD5 version of "cocksrock." But you can easily MD5 hash "cocksrock," and see that it is the same hash. This is the basis of cryptography.

So while it doesn't prevent copying, neither do the methods we use now. However, counterfeits are not possible now. We still use things like holographic foil and stamps as verification of identity. This uses maths. You can be 100% certain.

Buy ethereum

Also, I probably wasn't very clear on how altering the signature is a lot like how websites verify passwords. Basically the idea is that if you change the input of a hashing algorithm even a bit you get dramatically different results. This makes it impossible to compute backwards, but easy to verify. If mathsfags prove P=NP this all falls to shit and the beginning of what we have started to do with these delightful maths will have been for nought.

Also, I'd like to point out that copying is essentially protected against, just not completely because it cannot be. So if you sign a message "hello world" and I can verify with your public key that this was signed by you on May 25, 2016 at 10:52AM, then I can in theory copy that entire message and its corresponding signature and impersonate you at that immediate time. Say you had signed a message "Yes, this is me, John Alcorn" at that time and date, 10:52AM. I could take that and go somewhere else and post that whole message and it would verify. Now, I could not sign any further messages with the key, so its of limited use. Also, as time passes, this becomes basically pointless, as it will have been signed in the past and the copier could not sign any new message (which they had never been able to do). So it's not a very /practical/ exploit. It's worth mentioning though, as the alteration of a signed message by someone other than the owner of the private key is completely impossible.

>I'm going to go do some research and see if I can learn all there is to know about using blockchains

lol

I'mma go learn how to build mathematical trading models to make big $$$...

looking to skim a few books over the weekend and get my first six figure finance job by Monday!