Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#1992

All these are examples of digital signatures. The other use case would be encryption :slight_smile:

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#1993
  1. Private key is long random number, I must keep secure of other people. From Private key, I can generate public key . But is impossible to guess private key from public key.

2.A: Encryption, Everyone can use my public key to encrypt message and send to me. But only I can read message after I decrypt it by my private key.
B: Digital signature. To identify, it was me who sent transaction.

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#1994

  1. As the words denote, one is public (visible to all), and one is private (only visible to you). Oneā€™s public key is in essence their mailbox, and oneā€™s public key is a translator.

  2. Digital signatures and encryption.

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#1995
  1. Describe the concept of public and private key with your own words.

The public key is a key which is open for the public and can be used to encrypt information and the private key is only visible for the owner of that key and with this key the encrypted information can be decrypted. It is always possible to go from private key to public key but not the other way around.

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

Use case 1: Encryption. An example is the message from Alice to Bob. Bob generates a private key and a public key. Alice can encrypt the message with Bobā€™s public key and Bob can open the message with his private key.

Use case 2: Digital signatures which is more used in cryptocurrencies and blockchain. It is about verifying who sends a message. An example is when Alice sends Bob a message. Alice generates a private key and a public key. The message to Bob is signed by the private key of Alice. Bob can verify this message through checking if the signature and the public key match.

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#1996

  1. Describe the concept of public and private key with your own words.
    Public key is a key which everyone can see and it is generated from private key which no-one can see.

  2. What 2 use-cases can public key cryptography be used for?
    Encryption-Sending.>Receiving messages
    Digital Signature->Sending/Receiving transactions

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#1997
  1. The concept on the public and private keys was for security and so that we can send bitcoin to each other and verify where it came from
  2. You Put your public key out for people to send bitcoin too or you can use digital signatures to verify anything
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#1998

  1. A public key is a series of numbers generated by another key (a private key), that itself can encrypt or sign a message.
    A private key is a series of random numbers generated a computer, which is used to generate a public key.
    The public key can encrypt a message, but cannot decrypt it - only the private key can.

  2. Encryption & digital signatures.

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#1999
  1. Private key is what it says it is, (private). You lose this key, you lose all access to your funds. Public key is generated by the private key and Public key is also what it says it is (public) everyone can use this key to send you a message and only your private key will be able to access and read the message.

2)Encryption and digital signatures

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#2000

Both of these are examples of digital signatures, the other use case would be encryption :slight_smile:

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#2001

  1. Describe the concept of public and private key with your own words.
    A private key is a generated random number, while a public key is a mathematically generated key from your private key too share everywhere and can be used too encrypt messages,or too sign a message.

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

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#2002
  1. Public key is used to encrypt the message. The private key is used to decrypt the message.
  2. Sending encrypted messages and digital signatures.
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#2003

  1. Private key is a very random number that your computer will generate, it shall not be published or sent to anyone.
    Public key is generated from private key and itā€™s sort of your wallet address as well, This wallet address or public key has a mathematical relation with the private key.

  2. Encryption and digital signature

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#2004

  • Describe the concept of public and private key with your own words.
    Ans: A private key is a large random number that can be the identity of a person. This key must be kept secretly. The public key is a value that is derived from the private key by applying some mathematical formula to the private key. It is publicly visible.

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

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#2005
  1. A private key is a random number generated by your computer when a private key is needed. Through a one way formula, you can get a public key.
  2. Private and public keys can be used to send secret information through a public space, the person who wants to send you a secret message encrypts the message with your public key. Now only your private key can decrypt the message. If you would like to send a message the other way around you would have to encrypt the message with that personā€™s public key, generated by a private key.
  3. (2B) The other case of use is to verify who sent something. If I sign my message with a private key, the receiver can see if the messengerā€™s private key matches my public key. If it does, the receiver will know I was the messenger.
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#2006

1.public key is used for encryption while the private key is used for decryption in order to protect it from someone else.
2.public key can be used for encryption and verify digital signatures of the private key.

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#2007
  1. Describe the concept of public and private key with your own words.
  • a public key is derived from a private key. private keys should be kept secret but public keys are shared.
  1. What 2 use-cases can public key cryptography be used for?
  • public key cryptography is used for encryption and authenticating the source of a message.
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#2008
  1. Both are used for cryptography. Private key is an unique identifier for the originator then coded to a public key for transmission to the receiver in a public platform. This is also done in the reverse.
  2. Digital signature and encrypting mail. This is needed for security.
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#2009

Homework on Public and Private Keys - Questions

  1. Describe the concept of public and private key with your own words.
    A private key is super-secret and not shared. From it, one or more shareable public keys can be generated. A sender will typically use the private key to encrypt something such as their own ā€œsignatureā€ or even an entire message. The corresponding public key can then be used to decrypt the signature. Successful decryption proves it was originally encrypted by the private/public key pair ā€œownerā€
  2. What 2 use-cases can public key cryptography be used for?
    Encryption is used to obscure the content of a message for transmission over an unsecured channel. Bystanders can see the message but do not know what it ways.
    Digital Signatures utilize a private/public key pair to allow the recipient of a message to know it really did come from you. You use your private key to encrypt your signature. Anyone can decrypt and see your signature using your widely known public key.
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#2010

  1. I understood private and public keys to be like the input/outputs in the functions we just did. Private key is the input, public key is the output.

  2. encryption & digital signatures

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#2011

  1. Public keys are very large, very random numbers (some random generators are better than others). Public keys on the BTC block chain are generated using the ā€œeliptical curveā€ cryptography calculations. The public key can be used to hash, transaction or communications. It also is used to create addresses for receiving BTC. But the private key is needed to access anything hashed by the corresponding private key. Signatures are different than private keys but are generated from private keys to identify the source of a message or transaction without revealing the all important private keys. A person can use someone elseā€™s public key and their signature to verify that the source of the message or transaction was, in fact from the same person, the correct person.

  2. All I can think of now, is crypto transactions or messaging. Basically all data sent on the net is a ā€œmessageā€ of some type. Either just communication or financial. But it could be any type of information sent on the net.

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