Homework on Public and Private Keys - Questions

[Maki]

https://metamask.zendesk.com/hc/en-us/articles/360015289632-How-to-Export-an-Account-Private-Key

[manifesting_magic]

cool! I saw how to do it for metamask. Thanks!

[manifesting_magic]

Question: How does a private key get used to sign a bitcoin transaction without revealing its string of random numbers?

[Paval25]

1. In essence, private keys are very large numbers that are generated using a computer, but kept secret from any other party other than the owner of the private key. The owner of a private key can use it cryptographically to sign a crypto transaction, whereas the public key which is generated from the private key can be shared openly and used by others to verify that the transaction was sent under the signature (and authority) of the holder of the corresponding private key. It is not possible to back-calculate the private key from the shared public key, so it would not be possible for a third party to spend the crypto owned by the holder of the private key just by using knowledge of the public key.
2. The concept of public and private keys has two major use cases: encryption and digital signatures. Digital signatures (as described above under question 1) is the use case most applicable to cryptocurrencies.

[Yoka]

1. A Private key is made by your computer, which is kept secret by the owner.The Public key is derived from the Private key and can be seen by the public and shared with others. This public key can be used to encrypt messages, which makes the message unreadable in a public network where everyone could see your message, only the private key which the public key is derived from can be used to make the message decrypted (making the message readable again.)

2. 1. It can be used to encrypt messages
   2. It can be used to identify the private key of the sender if a message is signed with signature.

[Marcelo]

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

The private key is the alphanumeric sequence that allows you to acess your information withim a blockchain. Its possession determines whos controls the content inside the wallet it opens.
The public key is the adress, also a alphanumeric sequence, that is public. Everyone whos want to send you some information (or value) has to use your public key.

The public key serve as a tool that the person wishing to send you something uses to crypto that information.
The private key is the only key that can decrypt the information that you received.

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

The two major uses cases are encryption (to keep de information content protected from the outside view) and digital signatures (as a way to certify that the metadata about the information is true).

To the curious, the timestamp of a file was the source problem that generated the debates about the blockchain technology in the 90’s.

[mkhuang]

1. Describe the concept of public and private key with your own words.
   Private key Public key is derived from private key (which is known only to the owner of the private key). The generated public key is known by other people.
   We cannot generate private key from public key but we can generate public key from the private key

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

1. To encrypt a message, receiver decrypts with their own private key
2. To create digital signatures, receiver decrypts with author’s public key

[ErrorCode]

1. Describe the concept of public and private key with your own words.
   A private key is a random generated number. A public key can be generated from the private key and can be shared with anyone as long as you keep the private key secret as you can never derive the private key from the public key. The public and private keys pair are used to encrypt/decrypt data that has been encrypted by the key set.
   Private keys also able to create digital signatures that can verify the identity the owner of created /delivered digital data. The receiver can verify the sender by processing the attached signature with the sender’s public key.
2. What 2 use-cases can public key cryptography be used for?
   Encryption and digital signatures.

[MetaDonGrubber]

Homework on Public and Private Keys - Answers

1. Private and Public Keys are a pair of astronomically large numbers created as mathematically related through the process of asymmetric encryption. In this process, a large number is randomly generated to create a Private Key. A Public Key is then asymmetrically generated from the Private Key. This Private Key is energetically impossible to determine from the Public Key with today’s current technology, hence the pair are said to be secure.

2. What 2 use-cases can public-key cryptography be used for?
   a. Encryption of messages: Messages that are encrypted by the Public Key can only be read after it has been decrypted using the correct (original) Private Key.
   b. Digital Signatures: Identities of sent signed message senders can be confirmed using published Public Keys.

[UFAME]

1. Public keys are created from private keys and are open to viewing by others, typically used in unsecure networks forums such as twitter, blogs, etc. Private keys are created by a large random CPU generated number, so large that it is practically impossible to recreate the same number.
2. For encryption and for digital signatures

[Ozarkshrub]

1. Describe the concept of public and private key with your own words.
   a. Private keys are selected by the user to generate the public key. the public key can be used by anyone to send info/bitcoin to the user, it can never be used to reverse the process making it completely secure.

2. What 2 use-cases can public key cryptography be used for?
   b. They’re used for digital signatures and encryption.

[Gene1]

1. a private key decrypts information that was encrypted using a public key

2. for encrypting digital signatures and data

[Maki]

@Gene1

encrypting digital signatures and data

Encrypting data and digital signature.

[baads]

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

Public key is a key that is public for others to see. Even tough open to others, they can not use this public key to misuse it.

Private key is a key that is randomly generated for a person to be kept secret. If this private key is given to anyone else, they have the power to misuse it by pretending to be the person who owns the private key.

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

Digital signature and encryption.

[Emmi]

1. Describe the concept of public and private key with your own words.
|-|Each private key can generate public key. Public keys can be visible for anyone.
|-|The sender will use the public key of the receiver to encrypt the message, the receiver then uses his private key used to generate the public key in order to decrypt the message.|

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

• message encryption and digital signature

[maria_b]

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

A: Once getting a wallet i am given a private key which i must keep safe not to loose my BTC, i.e. stolen assets or simply not being able to access them anymore, the key is encrypted and in future it will be used to produce digital signatures so other people on the network can acknowledge i spent BTC. Public key is generated from private key and this one can be shared, private key can not be shared, if it happens then other people can get hold of our asset BTC. A Bitcoin address is generated from public key, now on the network i can receive and send BTC

2. What 2 use-cases can public key cryptography be used for?
   A: By a - Encryption through the public network, where b- digital signatures are identified for their integrity through a one way function since public key makes private keys hidden and these sign transactions on the network and therefor everyone on the network can see how much BTC is being sent and received.

[Fengzi]

1. A private key can be used to decrypt a message, and it is used to prove an individual sent the message. It is never to be shared with others. A public key is shared with others. Anyone can use the public key address to send a message to the person. A public key can also be used to encrypt a message. A private key creates the public key but never vice versa.
2. Encryption and Digital signatures

[ryan_n]

1. Describe the concept of public and private key with your own words.
   A private key is a randomly generated unique number. A public key is mathematically derived from the private key. When data is encrypted using a public key, only the private key can decrypt it. Sender of a data can sign the data using the private key, and the recipient can verify that the data was actually sent by the sender by using the sender’s public key.
2. What 2 use-cases can public key cryptography be used for?
   Encryption and Digital Signature.

[RobGu3]

Hi! Rob here on Public and Private Keys:

1.) In my own words, the Public and Private Key concept in Cryptography is a one-way function that secures the identity and data integrity of users on the network through encryption and digital signatures.

2.) The 2 use cases that Public Key Cryptography can be used for are encryption and digital signatures.

[Chuks]

1. Private key is a random set of numbers generated by a computer that is used to generate a public key through a unidirectional computation. Private key can be used for digital signatures and public keys are used for encryption.

2. Public key can be used for encryption and for generating addresses in cryptocurrency. It is also used to confirm the origin of a digital signature signed by a private key.