Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#2133
  1. Describe the concept of public and private key with your own words.

The private key is a randomly generated key and the public key is generated from the private key but not vice versa

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

Encrytion messages is one use case where a message is encrypted using the public key of the receiver that the receiver can decrypt using his/hers private key

Digital signature is the other use case (in bitcoin) where the bitcoin is signed by the private key of the sender to the bitcoin address that is generated by the public key

1 Like
#2134
  1. Private and public keys are used in cryptographic networks for encrypting and decrypting messages as well as identification purposes.

By running a private key through an algorithm, one gets a public key, which is tied to the private key and can be shared openly. However, one cannot use a public key to derive a private key. The encryption only works in one direction.

Also, the private key must be kept secret, since it can be used to derive the public key, which can be abused by others for encryption/decryption and identification in place of the private key’s original owner.

  1. See above - encryption and identification
1 Like
#2135

  1. Generally speaking, public keys are used to encrypt messages, whereas private keys are used to decrypt messages (and to generate the public key in the first place). The public key is dependent upon (created by) the randomly generated private key. The public key, as the name implies, can be used as a public address or linkage to the private key.

  2. Sending or receiving encrypted or verifiable transactions/messages across an unsecured medium.

1 Like
#2136
  1. Describe the concept of public and private key with your own words.
    Public allows receiving message openly and is safe to share. Private is to be kept secret to be able to send message.
  2. What 2 use-cases can public key cryptography be used for?
    Share address to allow to receive encrypt data. Generated by using private keys
1 Like
#2137

  1. Describe the concept of public and private key with your own words.
    Theres a Private key that you keep to yourself, this private key when making a transaction goes through a hash function which gives it a public key that people can see and transact with. The Public keys don’t change the private keys.

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

When you are making a purchase or some type of transaction you can access your crypto private keys with your digital signature to ensure you are the owner. The digital signature sends the private key through a hash function which people can see those keys as a public key. The public keys all have a historical transaction block. So with all this its easy to prove the owner of the private keys and be used as a form of transactions.

1 Like
#2138

  1. Private key is used for signing a message (transaction) and is used for decrypting the message. Public key is generated from Private key and is used for encrypting a message.

  2. There are two use cases for public key cryptography - 1) Encryption and 2) Digital signature (identification).

1 Like
#2139

  1. The concept of public keys are like your mailing address it is public info, your private key is the keys to enter your home, only you have the key.

  2. public key cryptography can be used for authentication as well as integrity verification

1 Like
#2140
  1. The private key is a random number. With a mathematical forumula the private key will generate the public key. It is impossible to reverse the process, i.e. deriving the private key from the public key which makes it very secure (if you keep the private key a secret). The public key can safely be shared with anyone.
  2. Use cases
    2.1 Encryption of data. A message + the receivers public key encrypts the data. The receivers private key will decrypt the message.
    2.2 Sending crypto currencies from a wallet with the public key and the signature (derived frÄn the private key).
1 Like
#2141

Homework on Public and Private Keys - Questions

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

A private key is a large number that is chosen randomly. From this number a public key is derived via a formula. Anyone can interact with the public key but the private key is used to unlock and manage anything sent with the public key.

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

Encryption and digital signatures.

1 Like
#2142
  1. A public key is like your house address and allows anyone to digitally send encrypted information to it that can’t read without having a special house key. A private key is like a special key to your house that allows any digital messages or transactions sent to your public address to only be decrypted by the only person who has it.
  • Don’t ever lose your private key or you will also lose or give away anything you are storing in your home
  1. Public key cryptography be used for encryption of digital information and the verification of digital signatures.
1 Like
#2143
  • Describe the concept of public and private key with your own words.

In the world of encryption, the concept of public and private keys are the mechanism used to encode and decode messages. Private keys are randomly generated numbers from your machine, and the public key is a derivative of that private key. When messages are sent or received, public keys from the sender or receiver (depending on the type of transaction) will either restrict access to the message/transaction based on the keys used or act as verification of the transaction as a signature.

  • What 2 use-cases can public key cryptography be used for?
    The 2 use-cases are for sending encrypted messages and for creating digital signatures.
1 Like
#2144

Public keys are derived using the elliptic curve, not hash functions. The keys can either be used for digital signatures or encryption :slight_smile:

2 Likes
#2145

1a. Private key is never shared. b. Public key is shared with everybody.

  1. encryption and digital signatures
1 Like
#2146

  1. A private key is a specific address that sends a specific message or transaction. A public key is an extra step put in place so that no one can see what the private key is, but they know who sent it.

  2. The 2 use cases for public key cryptography are a) encryption (hiding a specific message), and b) digital signatures to prove that it was this specific private key that paid or sent a message.

1 Like
#2147
  1. Describe the concept of public and private key with your own words.

The concept of Public and Private Key cryptography is to encrypt a message or object and send it securely from one individual to another, so only those who are meant to be able to read or understand what has been do so. for example i can genKeyPair I would have both the private and public keys, I keep the private key private and do not share it with anyone if I do the point of it is lost, the public key can be shared with everyone but is derived from the private key but the private key cant be derived from the public key, this enables a message to be encrypted with the private key and read with the public key, so you only really want those who are going to need to read or want to read you encryptions limited also.

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

there are many instances where the private and public key cryptography can be used but the two main use cases are for sending an encrypted message, and the second is for providing signatures to enable proving the source of a message.

1 Like
#2148
  1. Describe the concept of public and private key with your own words.
  • the concept of public and private keys is essential to secure information in which a private keys hold access to the information and public key is given out to the people you wanna interact privately for example if somebody wants to send you a message but you and that persona don’t want anyone else to see that message you as a receiver will give out your private key to the person who wants to send you a message and that person would encrypt the message and you would receive the encrypted message which you can decrypt then using your private key , so this concept is very useful to secure transect information or value.
  1. What 2 use-cases can public key cryptography be used for?
    -first use case of public key cryptography is to encrypt the message for the private key holder
    and secondly is it used to verify the digital signature of sender .
1 Like
#2149

  1. The private key is a randomly generated number, from it the public key gets derived. It’s possible to find out the public key via the private key, but impossible the other way around.
    The private key has to be kept secret, the public key may be freely spread around.

a) Encryption
b) digital signatures

1 Like
#2150
  1. Public and private keys are used for sending secure messages and validating the senders identity.
  2. The 2 use cases for public key cryptography are encryption and digital signatures
1 Like
#2151

  1. Your computer generates a random number in which your private key is derived. In turn your public key
    is derived from your private key. Your wallet address is derived from your public key. Everyone can see
    your wallet address, but can not see your public key or your private key. You can not interact with the
    wallet address unless you have the private key. There is no way to reverse engineer your wallet
    address to be able to derive the private key. It only works one way and not the other.

  2. a) Used for encrypting messages.
    b) Digital signatures.

1 Like
#2152

  1. A private key is a secret number which is actually like the key to your crypto, that has to be kept private. A public key is a key derived from the private key number that you can share with others, they use it to encrypt data that you with your private key can decrypt.

  2. Encryption and digital signatures.
    Encryption: the sender encrypts the data with the public key of the receiver so that the receiver can decrypt that data with his private key.
    Digital signatures: this is used when you send data to the public key of the receiver and signs the data with the private key of the sender. It doesn’t neccessarily encrypt the data.

1 Like