Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#4187

And the other use case is encryption.

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#4188

1.The public key is used to receive information. And the private key is used to decrypted to message.
The public key is generated from the private key.

2.Cryptography uses these key in encryption and digital signatures.

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#4189

  1. Describe the concept of public and private key with your own words.
    Private key is a key known only to the owner and the public key is shared publicly. During encryption, a public key is used to encrypt a message and private key is used to decrypt it. In digital signature, a private key is used to signed the message while public key will be used to verify the message.

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

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#4190
  1. A private key is a random number only known to the owner or to whom he/she gives it to. A public key is derived from the private key and this public key is visible and made public on the network.
  2. Encryption e.g. emails, messages and digital signatures e.g. in messages or transactions
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#4191

  • Describe the concept of public and private key with your own words. -->
    They are a pair of keys that are linked.
    Public key: Everyone can see.
    Private key: Only held by you. Not to be shared.
    With the private key, we can generate the linked public key but not the opposite.

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

  1. Encryption: You can encrypt a message with a public key and that can only be decrypted by the correct private key.
  2. Digital Sign: You can sign a message with your private key and that can be validated with the public key to ensure it was actually the person holding the private key who signed it.
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#4192

  1. the private key is a random number generated for you and you should keep it safe. Public key is a random number generated by or driven by the private key. Its impossible to go from public key to private key. Private key is used as signeture or to open encrypted massage sent by using the public key related to the private key.

  2. encryption and signeture

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#4193

Homework on Public and Private Keys - Questions

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

This is quite similar to the hash function and this is the core of the crypto currencies mathmatical concept that provides them with a superior and security and authenticity. From a random number a very large private key is generated. This private key generates a public key. This mathematics and algorithms were originally created for military purposes. In a combat situation, a general wants to deliver secret messages to its liutenants, but the channels are compromised (an open internet for example). The enemy is wathcing what goes thu the network. Therefore the general needs a reliable way to send secret messages. In order to do so, the receiver generates the two keys, but keeps very secretly and guarded the private key, and provides the public to the other side. It doesn’t matter if enemies get access to the public key. The sender uses the public key to encrypt the message and sends through the compromise channel. The only way to read the message is by using the private key. The enemies will only see gibberish.

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

One of the use cases is already explained. The other use case, which is key for the Bitcoin is that Public and Private keys can be used as a digital signature. Let’s say I want to stamp with digital signs to my documents in order to avoid counterfeit. I provide my public key to anyone, and everytime I deliver a document I also provide a digital signature genarated with the private key. The document plus the digital signature and public key I can demonstrate to the community that the document is authentic. The only way to place the digital signature is with the private key.

In Bitcoin, anybody knows my public key which is basically my bitcoin address. Anytime I make a transaction, I have to place a digital signature that the rest of the ledgers can verify the authenticity. If I attempt to make a transaction without this digital signature, the system will reject the transaction.

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#4194

  1. Public key is created from the private key and should be hidden. Encryption is done by using private key and decryption is done by public key - asymmetric encryption. If private key is lost = information cannot be accessed.

  2. Transfer secret documents that need a key to open them and having access to a digital wallet that’s connected to a business account.

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#4195

  1. Describe the concept of public and private key with your own words.
    Public and private keys are an asymmetrical mathematical function. They are a significant part of cryptography as they are used as a means of (a) encrypting and decrypting sent information/data and (b) a means of ensuring the sender’s identity (integrity via digital signature). Again, this process is unidirectional, so although the public key is generated from the private key, it is almost impossible to determine the private key from knowing the public key. This ensures the validation of the sender and keeps the information/data ‘secret’ or hidden.

  2. What 2 use-cases can public key cryptography be used for?
    Used for encryption, and’sdigital signatures’

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#4196
  1. A private key is a randomly generated large number from which a public key can be derived. The private key needs to be hidden from others while the public key can be shared. You can only go from private to public and not the other way.
  2. These are encryption and digital signatures.
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#4197
  1. A private key is a randomly generated number. Following certain function public key is generated from the private key. Private key is secret and should only be known by owner. The public key is open to anyone. It is imposible to get private key from public key.
  2. Private and public keys are used for encryption and digital signature.
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#4198
  1. Private key is a random number generate by computers. With Private key you can create a public key. But never share your private key with someone.
  2. Encryption and Digital Signatures verify who sent the message.
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#4199
  1. Describe the concept of public and private key with your own words.
    In cryptography, the private key is like a very large random number that contains an electronic signature and the public key is linked to that private key. The private key is necessary to decrypt any messages that were encrypted with the public key. In cryptocurrencies they are used to make sure that the owner of the funds signed the transaction.
  2. What 2 use-cases can public key cryptography be used for?
    Encryption and Identification
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#4200

[quote=“ivan, post:1, topic:8431, full:true”]
Homework on Public and Private Keys - Questions

  1. Describe the concept of public and private key with your own words.
    This concept is an old one, where a message intended to be private can be encrypted and sent using a public key through an open and central network in such manner that it can be decrypted by the receivers’ private key.
  2. What 2 use-cases can public key cryptography be used for?
    a. Encryption, which is related to keeping a message private when sent to another party.
    b. Public and Private Keys, are about assuring the integrity of the private message. Its purpose is to identify who sent a particular private message. Bit coin transactions work through a comparison of signature and private key of who sent the message, as there is no central entity that keeps track of each transaction.
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#4201
  1. Private keys are randomly generated, and public keys are then extracted from that. Public keys can be taken from private keys, but private keys cannot be taken from public keys. Messages are encrypted using the public key and then decrypted using the private key.
  2. They are used for encryption and identification
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#4202

  1. Private and public keys are a method of encryption. A private key is a random and unique number that is generated and given to a person. From the private key, a public key is generated through a one way function. Both are needed to securely exchange information.

  2. Message encryption and digital signatures.

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#4203

1.) Public and Private keys are randomly generated numbers used to ranger, receive, and verify data.

2.) Encryption, Verification (Digital Signature)

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#4204

1.) Private and public keys are used in encryption and digital signatures. For example in an open network where are many spectators, it is important to encrypt personal messages, and it is important to idenfity the user as the user who it should be. Every user got a private and a public key. The private key can only be seen by the user, the publich key can be seen by everyone. The public key results of the private key. When User-A sends a message to User-B, User-A gets the public key from User-B and encrypts his message, that only User-B can read it cause he got the private key to decrypt it.

2.) In Encryption and Digital Signatures. For example in a private Message to another user in a discussion board or in cryptocurrencies like bitcoin.

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#4205

  1. The private key is a random generated “number” which is only known by the owner and the public key is the “number” based on using the private key which is known to everybody who cares and can be used to transact or communicate safely.

  2. It is used to create a bitcoin address, if you like to have a transaction or it can be used to decrypt a message/data.

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#4206

  1. A private key is a number that is generated by a computer which is not visible to the public. With this private key a public key, that is visible for the public, is generated. This way the two keys are linked.
    Like hash functions the generation of the public key is irreversible, meaning that you can get a public key with a certain private key but you cannot get the private key by knowing the public key.

a) Encryption
b) Digital signature

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