Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#5048

private key is randomly made kombination of numbers,that can not be hacked or guessed. without private key you can not store bitcoin or any oher coins. public key is derived from private key,and it is used for sending and receiving coins.

two use cases for public key are indentification and confidentiality .

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#5049
  1. A public key is seen by everyone and can be used to accept messages, funds, etc and is tied to the private key. The private key cannot be seen by anybody and is a one way function so nobody can get your private key from your public key.
  2. Encryption (i.e. messages) and Digital Signatures
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#5050

  1. A private key is a very large number, which needs to be kept private and not shared with anyone. From the private key, another number called the public key is generated and shared online.

  2. the main two use-cases are
    2.1) to send an encrypted message : person A wants to send an encrypted message to person B. A will use the public key of B to encrypt the message in such a way that only B’s private key will be able to decrypt.
    2.2) to use a digital signature : A sends a message to B and A digitally signs it to confirm its identity (and provenance). A does so with his private key. B receives the message and uses A’s public key to compare it with the signature of the message, and if there is a correlation, then this confirms that the message indeed originated from A.

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#5051

  1. Describe the concept of public and private key with your own words.
    Private Key: is a very large random number generated randomly by our computer, it should be kept private.
    Public Key: is derived from our personal private key, and it is for the world to see. Can be used as an address to send something to, and then unlocked with the private key.

  2. What 2 use-cases can public key cryptography be used for?
    Encryption and Digital Signatures (Bitcoin uses this one)

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#5052
  1. Private key is basically a large random number than the computer generates. There are so many combinations that is extremely hard someone is able to generate exactly te same private key. It is meant to keep secret.

The public key is another number that is mathematically derived from your private key and it is meant to be shared. There is no way that someone can derive your private key from your public key (impossible).

  1. Encryption and digital signatures. For encryption, the message is encrypted with your public key that you give to the sender, and it can only be decrypted using your private key. For digital signatures, you generate a signature using your private key. The sender can verify that the signature is valid with your public key.
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#5053
  1. Public keys are generated based on a private key.
    Public keys are shared and are used for data encryption where the private key which is not shared is used to decrypt the data which was encrypted using the public key.

a) A public key can be used for encrypting data to be sent to the private key holder who is can decrypt the data using that private key.
b) A public key can be used to validate data signed using a private key was from the actual owner of that public key.

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#5054
  1. A string encrypted through the public key is decryptable only through the private key.
  2. Confidentiality: Only the person holding the private key has access to the unencrypted string, even though the encrypted one may be public
    Non-repudiation/integrity: a digital signature can be created only by the person holding the private key. In block chain technology this means only this person can authorize transactions from the wallet
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#5055

  1. A private and public key of an identity are two large numbers of a fixed length used in cryptography for encryption and digital signatures. A private key is randomly generated and should be kept secret by the user in question as anybody in its control could make the transactions they desired and control the crypto funds of a wallet that private key is derived from if it is the case of the identity being a wallet. A public key is asymmetrically generated from a private key using encryption.

  2. It can be used to encrypt messages directed to somebody in particular with that somebody’s public key or to sign digital transactions.

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#5056

  1. Public and private keys re basically use for encryption. The public key is generated from the private key which is a set of random numbers. The public keys cannot be reconverted back to private key even though it was generated by the private key.

  2. The public key is used for sending encrypted message and also sending funds.

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#5057

Public keys are used for encryption and allow you to send data securely and a private key is a unique random number that allows you to generate a public key.

  • Encryption - The public key is used for data encryption. Only a private key for that encrypted data can decrypt an encrypted message, meaning if someone get hold of your public key they still can’t access your private information
  • Digital signatures - The private key is used for signing transactions which can be used to verify that the owner of an account (who holds the private key) authorised a transaction
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#5058

A private key is used to create a public key. If you encrypt a message with public key, then it can be deciphered with the private key connected to that public key. Impossible to figure out the private key if you only know the public key.

It can be used for encryption or digital signature.

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#5059
  1. Private key is the one which must be kept safe, secure and private. It is the one which generates the public key, which is not private and it is used for creating BTC address.
  2. encryption and digital signature
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#5060
  1. Describe the concept of public and private key with your own words.
    When one has public and private key of an address, the person is able to read information that was sent to address and it was encrypted by public key.
    Also private key is used to make signatures on blocks that verify the transaction source.
  2. What 2 use-cases can public key cryptography be used for?
    Public key can be used as an address to where people can send you bitcoin.
    Public key can be used to encrypt message, that can be decoded only by the use of the private key.
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#5061
  1. The private key is (or should be) a key that is only accessible for the person who generated it. This means other people or computers cannot access it. The public key is generated from your private key in an one way direction (so you can’t generate the private key from the public key) and these keys are linked to each other.
  2. This makes it possible to use encryption and digital signatures on open transparent platforms like the blockchain. This means you can send messages / transactions encrypted on the blockchain so only the person who should see it can see or use the messages / transaction with his private key.
    Also it means you can use digital signatures, that are generated from your private key as well, which validates that the message or transaction is send by you. This digital signature for example is used when sending bitcoin transactions.
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#5062

Describe the concept of public and private key with your own words?
private key is only accessible to the person who has the private key. the public key is for everyone to see and is derived from the private key.
what 2 use cases can public key cryptography be used for?
encryption: secret message
digital signature: to identify yourself

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#5063
  1. Describe the concept of public and private key with your own words.
  • public key and private key makes it possible so that you can securely transfer information between 2 parties, so that the risk of information being intercepted or decrypted by a third party is almost impossible to occur.
  1. What 2 use-cases can public key cryptography be used for?
  • crypto transfer and encrypted email.
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#5064
  1. Private key is the secret key (at least it should be and the user - “creator” of that private key is the only one responsible to keep it secret and the only one who should use it when needed), created by user on computer mostly as a big random number, from which public key is derived and that public key may be then shared for specific encryption / cryptographic purposes. Both keys are used in combinations for encrypting and decrypting sensitive data.
  2. Encryption and digital signature
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#5065
  1. Private keys are used to generate public keys and sign transactions. Public keys can be used to generate wallet address.
  2. Digital signatures and encrypt data that only you can decrypt.
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#5066
  1. One starts off with a private key which then allows you to generate a public key allowing for encryption and digital sign off. Via encryption - a private key is generated, you use this to generate a public key which is then used by an individual allowing them to communicate with you which you take and de crypt. Via digital signature which a very common within crypto, deriving a private key allowing for communication/transfer to take place, verifying the message one would check the signature and public key to make sure it corresponds to the private key. The relationship is top down, Public to Private and not Private to Public.
  2. Encryption and Digital signature - explained in more detail in part 1.
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#5067
  1. Public key is derived from an encrypted private key that only you should have.
  2. Data can be sent from a public key to the private key holder that only he/she can receive. When sending data from your private key it can only be done by the private key holder and the receiver will only see the data if they have public key derived from the private key.