Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#4527

Homework on Public and Private Keys - Questions

  1. Describe the concept of public and private key with your own words.
    The public Key is for everyone to see. With it, the other party can encryp something in one way, but to be able to decrypt you must have the private key.

Mathematically speaking let´s suppose I have to huge prime numbers.
There are algorithms able to detect wether a number is a prime in a fraction of a second, therefore it’s fairly easy to generate a huge prime number. However if we multiply two prime numbers, it’s extremely difficult to determine the two prime numbers decomposed.

This is the encyption concept, but more elaborated.

  1. What 2 use-cases can public key cryptography be used for?
    First use case> To send a secret message. The receiver where I want to send my secret message generates its double key and makes me know the public one. I use the public key to encryp the message and I send to the receiver using a public channel. Everyone was able to see the public key and the encrypted message, but no one will be able to decrypt the message. In order to do so, the private key is required

Second use case> In a block chain, in order to sign a transaction I need the the double key. If I hold Bitcoin in my address, where everyone knows the public address, in order to send some Bitcoin to other person’s public address, I must be able to withdraw from my one. For everyone to recognize a legit transaction, I need to demonstrate with the secret key

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#4528

1.First the private key generates a public key, then you can use the public key to encrypt and verify signatures. You can use the private key to read the public key encrypted message and sign messages.

  1. Encryption & Digital Signatures
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#4529

  1. Public key is used to encrypt information and private key is used to decrypt information, you can generate the public key from the private key, but not in reverse. The public key is open to everyone meanwhile the private key should be only for yourself and must be kept safe in private.

  2. The first use case of public key cryptography is, encryption which means that in order to send a message in an open system where everyone can watch it, it must be encrypted. And the second use case is Digital Signature, which is used for identification and to verify the integrity of the message.

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#4530

  1. A public key is something everyone can see while the private key is something no one can see. The public key is derived from the private key but the private key cannot be know through the public key.

  2. Encryption and digital signature

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#4531

1.A public key can be shared with everyone- based on data and encryptions. But the private key is kept secret.
2. Encyption and Digital Signatures

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#4532
  1. Describe the concept of public and private key with your own words.
    Privatekey is generated by a random number, with this private key a public key can be generated mathematically.
  2. What 2 use-cases can public key cryptography be used for?
    Proof you have written or recorded something. Encryption and digital signatures.
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#4533
  1. Private and public keys are used for safety reasons. Private key is a random number and is the base for creating public key (via specific mathematic formula). Key pairs can be used for encryption or digital signature. Encryption is done using receiver’s public and the receiver can decrypt it via his private key key. Digital signature is done using sender’s private key and can be verified via sender’s public key.
  2. Public key can be used to encrypt transactions or verify if the digital signature is valid (comes from expected sender).
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#4534

  1. A public key is similar to you email address or an account number. A private key is similar to a password. Your public key is visible to everyone and necessary to send and receive transactions. A private key is for your own use only and should be shared with no one. Your private key signs your transactions in order to validate them.

  2. The two use cases for public key cryptography are encryption and digital signatures.

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#4535

The public and private key together, essentially create an address to send and receive funds. The private key is generated randomly by your computer, and used as a digital signature when sending funds. The public key is generated from the private key, and used to verify transactions.
Public is available to the public (duh) while the private key should be kept safe and private.

Public-key cryptography is essentially useful for 1. encryption and 2. digital signatures.

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#4536

  1. private: unique mathematical function(key). public: unique mathematical number containing private key digital signature

  2. a. to create a unique BTC address belonging to private key holder
    b. encrpyt messages to put out in unsecured networks

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#4537

  1. Encryption and digital signatures which use the hash function where the input is your private key and the output is the public key if I’m not mistaken.

  2. Can be used to verify that a payment has come from a specific source (identify)
    And also to allow you to use publicly without revealing your private key .

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#4538

  1. The concept of the private/public key infrastructure is based on mathematically generating a private key which is then used to derive a public key from that private key. The public key can be used to encrypt a message by anyone which is then decrypted by the receiver by their own private key. The public key can also be used to verify a digital signature that was created by a senders private key.

  2. Encryption and Digital Signature verification.

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#4539

  1. Private and public key pair is used to access information or bitcoins whatever is the case. First we generate private key, from private key we generate public key. Private key should be kept safe and secret and use as digital signature.

  2. Public key is used to share with the purpose of other to communicate with you, ie receiving bitcoin on your address through public key.
    Second public can be used to verify that the encrypted message was send by the authentic person. kinda used as digital signature verification purpose.

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#4540

  1. A private key is very important to keep safe, and private. Not to be shared, as who ever has the key could access your private information. The public key is for anyone to be able to access what you want to be in the public.

  2. Encryption and Digital Signature

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#4541
  1. Generating a key pair where one of the keys is visible to the creator and usable by them and the other one is publicly available. These keys have various usages, eg. encrypting a message with the receiver’s public key, or signing a message with the sender’s private key.
  2. Digital signature and encryption
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#4542

A private key is an encrypted key that governs the security of your wallet. A public key can be generated from your private key. The public key can then generate your address, the address is where BTC can be sent to, or from.

Public key cryptography can be used for sending an encrypted message and also to generate a cryptocurrency digital signature

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#4543
  1. Describe the concept of public and private key with your own words.
    ANS- private key(kept secured) is a random number or word that is generated for security; while a public is another derivative of private key that can bused for identification purpose(can be shared publicly)
  2. What 2 use-cases can public key cryptography be used for?
    ANS- a public key can be used for purposes like encrypting information and also used as an address where you could receive transactions via .(like identification purpose).
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#4544

A private key is a key which is held by each individual and is unique for them. A public key is generated from the private key and cannot be backtracked to check what the private key is. A public key is used to allow for other people who need access to the information to be able to access it once they recognise the public key.

Public key cryptography can be used for encryption and for digital signatures.

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#4545

Describe the concept of public and private key with your own words.
Public key is a derivate from the private key which is being used to encrypt data. Therefore, making the encrypted data accessible by using only the private key.

What 2 use-cases can public key cryptography be used for?
Message encryption and for checking if the message is being sent from the correct sender. (Digital signature)

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#4546

encrypicion your computer created a private key (large number) that derives a public key that verifies your private key and encrypts all your information.
to send a message you send your private key and the other person verifies your key by checking the public key.

sending private confidential material and funds

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