Homework on Public and Private Keys - Questions

[BobN]

Homework on Public and Private Keys - Questions

1. Describe the concept of public and private key with your own words.
   Concept of public and private keys is in having a mechanism to safely verify a sender/transaction or to encrypt messages/transactions

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

[Dkhtime11]

A private key is a key that the user must keep secret, used to recover funds, and not shared with others. The private keys are generated by the wallet and then generate the public keys which are shared with the public to conduct transactions. The private key can never be found by knowing one’s public key.

Public key cryptography can be used to send and receive funds as well as send and receive encrypted messages.

[Mauro]

@Bellantoni

A private key is a number randomly generated by the computer and you are the only one to know that number (unless you share it of course).

Of course. You don’t want to share it of course.

@Bellantoni

What 2 use-cases can public key cryptography be used for?
Case 1: When A sends money to B. B will know by the public key shown that it was A who sent the money.
Case 2: When a message is sent from A to B. Whether the message is encrypted or not, B will know who sent the message because of the public key equivalent to a digital signature that can be only connected to one person.

Both cases you mentioned are using digital signatures? What abou encryption? How can encryption be used with the public and private keys?

[Mauro]

@Emjay

1. private key is your own personal key (used to unencrypt messages sent to you with your public key, and it is also used as a signature with your bitcoin).

Yes, we use the private key in order to generate a digital signature.

[Maxivation]

1. there is a public key which is there to be shared with the world. It is a soft of comparable with your bank number. Everybody may see it and with that key they can send you funds to your account. But the private key should be considered more like your accountnumber/password. With this key everybody can access your account (wallet) and take your funds

2. For either the Digital signatur or encrypting data

[Markshire_Crypto]

1. Public and private key cryptography is a way to encrypt certain information, with a sender of a message able to encrypt a message with the public key. Only one person/entity has access to the private key. I understand this concept to be similar to a one way hidden message channel, where you can only send information to a public key address that can only be decrypted by the private key.

2. Two use cases for public-key cryptography:
   (a) Encryption of messages. Send encrypted messages with public key, decrypt with private key.
   (b) Digital signatures for identity purposes.

[Rafael21]

1. Private and public keys come in pair to enable such things as encryption and digital signing. A private key is generated using random numbers. Using private key as input to another algorithm such elliptical curve digital signature algorithm (ECDSA), the computer can generate a public key that everyone in the network can see. It is possible to generate a public key from a private key but it is not possible (practical) to deduce the private key by using public key.

2. One use cases are end-to-end encryption where the public key is used to encrypt a message which only the owner of that public key’s private key can read. Another use is for digital signatures which uses private key to sign outgoing messages. Anyone can compare the signature and the public and confirm that both we produce by the same private key.

[Jaco_Vosloo]

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

   • Public Key - A key that is generated by a private key and is shared with the public, but does not compromise the security of the account.
   • Private Key - It is the thieves most precious possession, it open all the locks. This is used to encryption data.

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

   • Encryption - Protects the information
   • Digital Signatures - Verifies the sender.

[Alexandr_Els]

@ivan

Homework on Public and Private Keys - Questions

1. Describe the concept of public and private key with your own words.
2. What 2 use-cases can public key cryptography be used for?

1. the PUBLIC KEY is derived from the PRIVATE KEY
   Public key can be used to ENCRYPT messages.
   Public key can be shared to anyone.
   By using Public key you can send message to the RECEIVER (Who holds PRIVATE KEY)
   A PRIVATE KEY can be used to DECRYPT messages with a matching PUBLIC KEY.
   A sender can combine a message with a PRIVATE KEY to create a short digital signature on the message.
2. Public key cryptography can be used for ENCRYPTION & DIGITAL SIGNATURES

[Crypto_Daddy]

1. A public key is an identifier for data or transactions sent across the network thats created from your private key. the public key can be shared but the private key must be kept secret as anyone with it can decrypt the message sent to public key

2. one case is used as a digital signature to confirm where data or a transaction originated from and is destined too. another can be used to create another unique bitcoin address to handle payment in cryptocurrencies and provides layers of security to the transmissions of data or payments

[Kyle]

@ivan

• Describe the concept of public and private key with your own words.
  Public key is a cryptographic key that anyone can use to encrypt message intended for a particular person. usully comes from the private key.

private key-is something that someone uses to encrypt or decrypto messages that are sent to the public key

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

Encrypting and digital signatures

[DrKnugen]

@ivan

Homework on Public and Private Keys - Questions

1. Describe the concept of public and private key with your own words.
2. What 2 use-cases can public key cryptography be used for?

1. A public key you share with anyone who wants to send you an encrypted message. You use your private key to decrypt the message and you are able to read it. The private key are personal and you don’t share it with anyone. If you do, that person can decrypt and read your messages. It can also be used in the same way when sending currency.

2. People can use your public key to send encrypted messages that only you can decrypt and read.
   People can use your public key to send currency to you.

[voconget]

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

With public and private keys, in a trustless environment, two separate entities can exchange data privately and verify from which entity the data originated.

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

• Public and private keys allow sending encrypted data from a source to a destination over an unsecured channel. The data is encrypted with the destination’s public key. Only the destination’s private key can decrypt the data.

• Public and private keys also allow signing data. Data is signed with an entity’s private key. Other entities can then verify that the data was signed by the correct entity by comparing with the signing entity’s public key.

[terrydanaher]

A private key is a randomly generated number from which a public key is generated. Public messages can be decoded by the holder of the private key, but private messages cannot be decoded with the public key 2. Traffic encryption and Digital signatures

[I_T]

1. Describe the concept of public and private key with your own words.
   Private key is a random number. Public key is generated using the private key as input.
   The private key is to be kept private wheareas the public key is for the use of anyone interested.
   One cannot determine the private key corresponding to a public key.

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

[pepijnnabbe]

1. A computer can compute a random number being the private key. The private key goes as input into a hash function generating a public key. You can never derive the private key from the public key. You can verify a digital signature made with a private key, by verifying it with its paired public key.
2. encryption and digital signatures

[Erwin]

1 The private key is a random large number generated by your computer. a public key is derived from the private key using a mathematical formula. But it is only one way. It is impossible to go from your public key to the private key.
2 For encryption and digital signatures

[colgate_fresh]

@ivan

• Describe the concept of public and private key with your own words.
• What 2 use-cases can public key cryptography be used for?

1. Public and private key is kind of like having a chest, a lock, and a key to said lock. The lock was “keyed” specifically to fit that one specific key. You can send the lock (unlocked), and the receiver (the sender of the message) puts a (paper) message into a chest which has a latch that works with that particular brand of lock. The receiver (the sender of the message) closes the lock onto the latch, which locks the lock. The receiver sends you the chest, which you’re able to unlock using your key. Once the chest was closed, and your lock was affixed to the chests latch, even the receiver (sender of the message) could no longer open the chest. The lock is your public key, and your key is the private key.

2. You can both encrypt and sign messages using public and private key cryptography. You encrypt with the public key, and you sign with your private key. With signing, although the message is encrypted, anyone with your public key can unencrypt your message. Knowing that only your private key would mathematically be tied to your public key, if someone is able to decrypt a message using your public key, they know you’re the only one who could have encrypted the message using your private key. If the private key gets compromised, however, anyone can sign messages on your behalf, but they can also decrypt messages that were encrypted using your public key.

[ludvighatle]

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

1. Once you generate a private key, you get a public key at the same time. Your private key is a random generated key or number. It is basically impossible that once you generate a new key that it has a “collision” with someone else that has generated a key. Your private key gives access to your wallet and you can use it to sign bitcoin transactions. This is called a digital signature. Your public key is public, and in bitcoin today, it generates an address so people can send bitcoin to your wallet. So Private > Public > Address. You can NEVER go Address > Public > Private.

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

2. Public key cryptography can be used to encrypt messages. If you send a message to someone using their public key. They can decrypt the message using their private key. This is to avoid that everyone can see the message. The other is digital signature, which is used in cryptocurrencies. Here you can send someone bitcoin using their public key. And you sign the transaction with your private key.

[ibnalarabi]

1. A public key is a randomly generated number you share with others to encrypt information. This is generated from a private key which is used to decrypt the information, only those with access ti private key can decrypt the information from the public key.

2. Encryption & Digital signatures which are used to verify a senders public key and private key pair when verifying transactions.