Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#3022
  1. Describe the concept of public and private key with your own words.

-Public key is the key you use to share with others and they use to encrypt data only you can decrypt. The private key is the key you keep private and use to unecrypt messages so you can read them.

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

-Encrypt messages, Digital signatures

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#3023

A private key is a long list of random numbers generated by software. Other software uses the private key to generate a public key. Anyone can use the public key to encrypt messages that can only be read by the person who

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

Sending and receiving encrypted messages.

Adding transactions to a Blockchain through mining.

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#3024

Homework on Public and Private Keys - Questions

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

Private key is how you access your encrypted information generated or sent to the public key.

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

Signature to validate something is from you.
Encryption.

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#3025
  1. In encryption a key is made up of two parts. One you retain and one you give. When the public key is returned to you, you match it with the private key to do the transaction. In digital signatures, you send your private key. The receiver matches your private key to your public key to verify.
  2. Encryption and Digital Signatures.
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#3026

  1. Describe the concept of public and private key with your own words.
    public key encrypt information and private key decrypts. (Encryption).

  2. What 2 use-cases can public key cryptography be used for?
    Blockchain confirmation of transactions signatures or secure on your email (Digital Signatures).

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#3027

1.Describe the concept of public and private key with your own words.
Private key is a large random number and from this large number we generate (public key),

  1. What 2 use-cases can public key cryptography be used for?
    Digital signature and encryption.
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#3028

  1. Private and public keys allow safe and secure transactions or exchange of information between two individuals anywhere in the world. For these transactions to take place, a random astronomical number is generated called a private key. This key is then used to derive a public key by using a mathematical function known as the elliptical curve. The public key allows an individual to receive encrypted data or transactions that can only be unlocked by the corresponding private key.

  2. Currently, there are two use cases for a public key such as encryption and digital signatures. The public key is used to send or receive encrypted data/transactions on a public address. The public address is a hash that is outputted from the secure hashing algorithm by inputting the public key. Digital signatures are used to verify whether the encrypted data or a transaction comes from the right person.

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#3029

PoW uses SHA256 and doesn’t include any keys to function. Sending funds utilizes digital signatures and you can also use PK cryptography for encryption. :slight_smile:

#3030

Mining uses SHA256, users sign their transactions with their private key. :slight_smile:

#3031

Emails are secured using encryption not digital signatures. :slight_smile:

#3032
  1. a private key is a randomly generated number of which is then mathematically processed into a public key. the private key cannot be derived from the public key but anything encrypted by the public key can only be decrypted by the private key, and NOT the public key.
  2. For encrypting data and digital signatures.
    thank ivan this is a really helpful course :smiling_face_with_three_hearts:
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#3033
  1. two keys are generated, the private key (PiK) and the public key (PuK). The PiK is secret, and the PuK is derived from the PiK, such that the PiK decrypts a message signed by the PuK. Alternatively the PuK verifies a message was signed my the associated PiK (see below)
  2. use case A: encrypted communication. the sender encrypts the message with the PuK (freely available) of the recepient. That way only the recipients PiK can decrypt the message.
    use case B: digital signature: I sign a message with my PiK and everyone else can use my PuK to verify I really signed it.
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#3034

Describe the concept of public and private key with your own words.
Private keys are generated and have almost no chance of being the same as someone else’s private key, private keys then generate public keys. Private keys should be kept private as they allow whoever has them access to the thing you’re trying to protect - in this case a BTC wallet. Public keys can be shared with anyone as there is no way to find out the private key from the public key. You can find out the public key from the private key though.

Private keys can also be used to sign either messages or transactions to confirm who you are. While public keys can be used to encrypt a message which can then only be read by the private key holder.

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

  1. can be used to encrypt, send, receive and read messages.
  2. can be used to sign transactions in crypto wallets.
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#3035
  1. Private key is held privately. It is part of a wallet and is not shared. The public key is generated from the private key and shared publicly. The public / network can very its correctness. The public key creates BTC address and have rights to move bitcoins associated to it.
  2. Public key is used in
    a) Cryptography - person A has a private key, which generates a public key. A sends a public key to a person B. B encrypt data with A’s public key and sends it to A. A can read encrypted message using his private key.
    b) Digital signatures - A signs transaction with his private key, which generates a public key. B confirms the transaction’s public key.
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#3036

HTTPS uses digital signatures too, no? The https indirectly uses the public private keys i guess.
The digital signatures use encryption too, i guess.
Do you know if i’m right?

#3037

  1. A Private key, which is a very long number, is generated. From it, a public key is derived. That public key is then broadcasted, and used by other entities to encrypt messages which only your private key can decrypt. Similarly, your private key can digitally sign messages that only your public key can verify as yours.

  2. Encryption and Digital signature

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#3038

HTTPS uses encryption to encrypt data coming from a server. Digital signatures are often used in SSH if you want to use passwordless login you deploy your public key on the server and can then login on it without inputing password every time. :slight_smile:

2 Likes
#3039
  1. The concept uses an interdependent relationship of Public Key to Private Key to verify the authenticity of transactions between disparate parties.
  2. 2 use cases are digital signatures and communications encryption.
1 Like
#3040

Homework on Public and Private Keys - Questions

1. Describe the concept of public and private key with your own words.
Public and private keys provide a mechanism for sending and receiving encrypted messages over an open network and digitally signing messages - whether encrypted or not - to allow the receiver to verify the sender. Private keys are generated from large random numbers and held secretly by the sender. A public key is created from the private key and shared widely but it cannot be used to back into the private key.

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

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#3041
  1. A private key is a number generated by computer. Public key is generated from your private key. Send and receive encrypted messages through public key, but your private key decrypts.
  2. Encryption and digital signatures
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