Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#487

Thanks for link again! Schnorr signatures looks like a great development, especially for future when tx fees may be a lot higher and wallets may contain a few hundred smaller UTXOs due to people DCAing, making spending from the wallet more expensive. Coincidentally I was actually thinking about that lately.

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#488

  1. A private key is a secret key that gives access to a cryptocurrency, a public key is generated from a private key that is accessible from anyone in the public to input into the public key. The private key is only able to access the public key to receive an output which was an input.

  2. To decrypt messages and to verify messages through digital signatures.

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#489
  1. a pair of keys used by someone to sequrely send and receive data through a network or to verify someone identity
  2. encryption; digital signatures
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#490

1 Public and Private Keys are performed in Cryptography. Private Key is not to be shared and has the mesage encrypted where a public key is open for everyone to see which is proof of signature but its linked to your private key proving ownership to the private key. But you cannot access the private with the public key.

2 Public Key cryptography participates in Bitcoin transactions. Used mainly for Traffic Encryption and Digital Signatures

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#491

1- The public key is used to encrypt data and can be shared with others, as the public name indicates. The private key must be kept secure and is used to decrypt the data encrypted by the public key. Private key generates the public key, thus they are related.

2- Two use cases are encryption, of messages for example, and Digital Signing documents.

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#492

1 Private key is private and gets created by wallet… Private key is used to create public key and is for publics use if they send you funds. Private key can also be used to encrypt or digitally sign/send funds or messages to other parties
2 Encrypt or digital signature

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#493

Very important, I seem to have understood that backwards. So the first number is a private key, and from that private key/number only then a public key is made

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#494

  1. Prime numbers have been something very intriguing for mathematicians since the advent of mathematics. These same mathematicians decided to put them into good use by using them to code and decode information. Prime numbers are important for encryption because when you multiply two together, the result is a number that can only be broken down into those primes, itself and the number one. Using rather simple math, agreed to rules and huge prime numbers, any message can be encrypted and decrypted. The public and private keys are numbers that are derived from those primes. One set of numbers are published openly for anyone to see and they become the public key. Another set of numbers are kept secret and they become the private key. Because the two sets of numbers are interrelated they remain entangled for ever and because of the enormous size of the numbers evolved it’s impossible for current computers to decode these numbers.

  2. Sending private messages, and keeping your credit card information private.

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#495

  1. Describe the concept of public and private key with your own words.
    A public key is created by using a private key to create a cryptographic signature. It has aspects of the private key but not close to the same alpha numeric signature. Private Key; no my key then not my money. Pubic key can be shown to anyone and used to send money, but food, etc.

  2. What 2 use-cases can public key cryptography be used for?
    1.) Paying a hooker.

  3. ) Doctors bill for penicillin

#496

  1. A public key can be only generated from the private key but the reverse is not true, ie it is impossible to determine the private key from a given public key. The public key may be known by anyone whilst the private key shall be kept a secret and only known by its owner.

  2. Encryption and digital signing. The public key can be used to encrypt a message for the recipient that owns the public/private key pair, who is the only one that can decrypt the message using the private key of the pair. A private key can also be used to digitally sign a given message or document that the recipient can verify using the sender’s public key of the pair.

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#497
  1. A private key is just a random number, but from that number you can derive a public key. The private key is used to sign messages. It doesn’t have to encrypt it, but that could be. When people receive a massage from you (your public key) they can mathematically verify that it is connected to the private key (without knowing it ofc).
  2. Encryption and digital signature
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#498

Yes, with eliptic curve cryptography, you can proof that your private key controls your public key without the need to reveil your private key.
https://medium.com/coinmonks/private-and-public-key-cryptography-explained-simply-4c374d371736

#499

[quote=“ivan, post:1, topic:8431, full:true”]
Homework on Public and Private Keys - Questions

1) Describe the concept of public and private key with your own words.

The difference between The Public Key Vs Private Key
The main difference between a public and a private key is their use. The Public Key, as its name implies, is public and open to anyone like your Account Number or address. The Public Key is used to encrypt data using asymmetric method of cryptography.

The Private Key however is a secret like your Pin Code or Password. Private Keys must not be shared with anyone. The Private Key is used to decipher messages/data sent to the receiver and it use symmetric method of Cryptography.

When someone wants to send an encrypted message/data, they can input the intended recipient’s Public Key (account number) provided by the recipient and use it to encrypt and attach the message/data before sending it. The recipient of the message/data can then decipher the message using their own related Private Key(Pin code). These encryption and decryption processes happen automatically.

*Generating Public and Private key pairs
There are several well-known mathematical algorithms that are used to produce the Public and Private key. Some well-respected examples of public private key encryption are RSA, DSS (Digital Signature Standard) which uses cryptography (Elliptic curve techniques).

The public and private keys are not really keys but rather are really large numbers that are mathematically related to one another. Being related in this case means that whatever is encrypted by the public key can only be decrypted/deciphered by the related Private key.

2) What 2 use-cases can public key cryptography be used for?

Asymmetric cryptography is typically used to authenticate data using digital signatures. A digital signature is a mathematical technique used to validate the authenticity and integrity of a message, digital document or cryptocurrency. It is the digital fingerprint or equivalent of a handwritten signature or stamped seal.

Based on asymmetric cryptography, digital signatures can provide assurances of evidence to the origin, identity and status of an electronic document, transaction or message, as well as acknowledge informed consent by the signer.

Asymmetric cryptography can also be applied to systems in which many users may need to encrypt and decrypt/decipher messages/data/cryptocurrencies including:

  • Encrypted email use of asymmetric encryption.
  • Encrypted websites and browsers also makes use of asymmetric encryption.
  • *Bitcoin and other cryptocurrencies rely on asymmetric cryptography as users have public keys that everyone can see and private keys that are kept secret. Bitcoin uses a cryptographic algorithm to ensure that only the legitimate owners can spend the funds.

The Difference Between Asymmetric vs Symmetric cryptography
The main difference between these two methods of encryption is that asymmetric encryption algorithms makes use of two different but related keys – one key to encrypt the data and another key to decipher it However Symmetric encryption uses the same key to perform both the encryption and decryption functions.

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#500

Really like your map of the world vision…Pretty awesome. clap, clap!

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#501

  1. Describe the concept of public and private key with your own words.
    Pri. and Pub key are one-way function. Only public key can be derived from its private one, not the other way around. The public key can be shared to the world without “any risk” but PRIVATE one needs to be kept safe and secret.
    2 facts about them: they are encrypted and used as a digital signature

  2. What 2 use-cases can public key cryptography be used for?

To send/receive crypto from a wallet / send encrypted message that only the private key will unlock to make it visible

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#502

  1. Describe the concept of public and private key with your own words.

    The public key you generate will then be used to generate a private key that you use. You will share your public key with the public so they can use that to encrypt a message they want to send to you, you will then use your private key to decrypt sent message.

  2. What 2 use cases can public key cryptography be used for?

    Public Key cryptography can be used for Encryption and Digital Signatures.

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#503

A:

  1. Private Keys can be used to generate public keys, but not the other way around. Public keys are known to the world, but what they encrypt can only be decrypted by having the private key. In crypto, the private key is the transaction sender’s signature which allows the receiver to prove that the transaction was sent by the owner of the public key.

  2. Use cases: Encryption, and Digital signatures

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#504

Q1. Describe the concept of public and private key with your own words.
A1. A private key is a personal code unique only to you (like an address), a public key is a code generated based off your which can be put out to the public (like a PO Box) and shared without fear of your private key ever being exposed (or address in this example :).

Q2. What 2 use-cases can public key cryptography be used for?
A2. Encrypted messages over a public/open network. Cryptocurrency transactions, from wallet to wallet.

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#505

1/ Describe the concept of public and private key with your own words.
A public key is derived from a private key, a public key is exactly what it says PUBLIC, meaning it can be shown to ALL of the public ( round the world ).
A private key is a extremely large random number,your SECRET key, & it must be kept secret…imagine somebody wanted to send you bitcoin, you would need to generate a random number, which would be your private number ( secret key ) which would also derive a public key number (Which the world can see ). We can then derive from a public key, a bitcoin address, to receive your bitcoin.
2/ What 2 use cases can public key cryptography be used for. ?
The first use case is to generate a public key to send to somebody, who wants to send you back your public key with an encrypted message inside, that only you can open because you have generated it through your private key.
The second use case is your public key derived from your private key,which can generate a bitcoin address.

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#506

  1. Describe the concept of public and private key with your own words.
    It is form of security. Your computer generates a random number a private key en derives
    a number from that to make a public key. Those keys are mathematical linked to each
    other. One encrypt the message and one decrypts it.

  2. What 2 use-cases can public key cryptography be used for?
    Encryption and Digital signatures

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