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I'm not a dev and I don't intend to be one. I'm just looking for some real life implications of it.
So far I only know that Bitcoin uses cryptography; I can't say I'm right. Some messanger apps also say that your chat is encrypted, I don't know whether they use it or something else.
This question came to my mind when I read the following:
SSNs are terrible identifiers. They suffer from two problems: the entropy problem and the symmetry problem. The entropy problem is that they are not random, so they’re pretty easy to guess, which is undesirable for something you are supposed to keep secret. The symmetry problem is one where you need to prove you’re legitimate. When you give someone your Social Security Number to prove your legitimacy, you’re no longer keeping it a secret, when it should be. Public key cryptography involves randomly generated secrets, so entropy is not an issue, and it does not reveal the secrets to anyone, so symmetry is not an issue. There is no single point of failure at every place you submit an ID because the submission does not share anything sensitive — it just proves you own the ID. *Source
So, this one can be a very practical use case for cryptography but I don't think any government has even thought of implementing it.
Are there other such use cases of cryptography in our real life?
25 sats \ 6 replies \ @k00b 2 Feb
Cryptography is for more than encryption.
So far I only know that Bitcoin uses cryptography to encrypt the transactions
The transactions in bitcoin aren't encrypted the way this sentence implies.
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Thanks. Maybe I'm short on words, I just know that Bitcoin uses cryptography for security. I've omitted that part.
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Public key cryptography can be split into 3 categories:
  • Encryption/Decryption
  • Key exchange
  • Digital signatures
The cryptography that Bitcoin uses are digital signatures. These are used to proof that you actually have the private key to a transaction output.
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Thanks. It seems cryptography isn't that difficult to learn. I was worried for nothing.
Is there a difference when we say "Cryptography" and "Public Key Cryptography"?
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It seems cryptography isn't that difficult to learn.
Well... it's a lot of math ;)
Is there a difference when we say "Cryptography" and "Public Key Cryptography"?
"cryptography" is an umbrella term for "symmetric" and "asymmetric" cryptography.
Symmetric cryptography is used for encryption/decryption and there is only one key. (The key for encrypting a message is also the key for decrypting it)
Asymmetric cryptography (public key cryptography) uses a pair of keys. (private key and public key)
When encrypting a message with the public key, only the one who has the private key can decrypt the message. This is useful for secure communication.
When signing a message with the private key, everyone can prove with the public key, that the message must have been signed by the owner of the private key.
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Well... it's a lot of math.
Lol, If I ever paid attention in maths class ;)
I based my response on your definition and his #873605
I feel grateful to you putting the basics of cryptography in so simple language. I'm starting to feel like an advanced Bitcoiner.
cryptography is as simple as putting numbers,letters, made up symbols on a piece of paper, or a sign, and then making a rubric for what those symbols mean ( the secret or secrets). those who have the rubric, are thus the 'keyholders' that can decipher the meaning behind the characters.
2 kids making a secret language to pass notes at school only they can read is cryptography
an inside joke between two friends at a party that only they get is cryotography
sharing secrets without publicizing the meaning behind the message
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SSL/TLS i.e. the “s” in HTTPS in every website you visit
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Thanks. I never knew it. Does the "s" mean our connection can't be hacked and we're interacting with the website in P2P mode?
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Thanks. The article is very simple to understand.
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10 sats \ 5 replies \ @dtonon 2 Feb
Create a open and censorship-resistant protocol like Nostr.
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Thanks. As more than 80% websites now use cryptography, why aren't they censorship resistant?
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10 sats \ 3 replies \ @dtonon 2 Feb
Encryption Cryptography is a possibly necessary, but not sufficient, condition for creating a censorship-resistant protocol.
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You mean we also require digital signatures and key exchange, right?
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10 sats \ 1 reply \ @dtonon 2 Feb
I mean "cryptography" (post updated). We also require a good idea on how to use it :)
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Ok. Thanks I got it.