Homework on Public and Private Keys - Questions

Blockchain and Bitcoin 101
#4988

  1. The private key is your personal key that only you know. With this private key you can open a public key that is open for anyone to see.

  2. The first use case is encryption. With this you can send an encrypted message by using the receivers public key. The user can then open/ read the message with their personal private key. The second use case is digital signature. This is the most common use case in crypto. This use case is about verifying who send a particular message or transaction.

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#4989

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

public key is a hash function with input of a private key. it is collision resistant and cannot be reverted. If you have a private key you can sign a message to be confirmed with your public key. Or you can encript a message with a recipients public key so only he can decypher it with his private key.

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

Encryption (Make unreadable: Only intended recipients can decypher)
Digital Signage (Verifiy: It was me who send the message/transaction)

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#4990
  1. Private key is for the owner and should not let anyone know. The public key is for other people to interact with you and feel free to share.
  2. Digital sign, and Encryption
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#4991

  1. Describe the concept of public and private key with your own words.
    Public and private keys are used to ensure secure and private communication inside a channel. No one can “listen” to what messages are exchanged. In cryptocurrencies, the goal is to prove that a spent transaction was really signed by the owner of the funds, all occurring over a public blockchain network between different participants. When you own cryptocurrencies, you don’t actually have coins in a wallet but a “private key.” Your “private key” unlocks the right for you to spend the associated cryptocurrencies and should remain private. In addition to a private key, there is also a public key and there is a cryptographic link between these two. It’s possible to know the public key if you own the private key. However it’s impossible to get hold of the private key using only the public key.

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

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#4992

  1. Public keys are derived from a given private key , and are displayed to all spectators in any cryptographic network. However, this private key is kept secret, with only the specific user having access to the private key. The private key is essentially a random number acting as an origin point, and the public key is a number that corresponds to this one.

  2. Encryption - If data is to be sent to this user, the sender encrypts this data (ie - a message) using the user’s public key which is then translated once it reaches the user by the user’s private key. Without this pairing of public and private keys, any data being sent back and forth becomes essentially gibberish.

    Digital Signature - To send data, private keys are created with the corresponding public key derived from this process. By sending this data, a user essentially attaches their own private key to said data as a “digital signature”. The actual key itself is not shared, but an outside user can verify the identity and authenticity of the source because of this attached digital signature that comes from the private key of the sender.

“Bob will see that the signature comes form the private key that generated Alice’s public key.” Basically, you can compare the digital signature to the sender’s public key to see if they correspond to one another. If they do, this source is successfully identified and verified (it’s all good in the hood).

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#4993

  1. A public key can be seen as a deposit function or a bank account and a private key as a withdraw function which is not open to the public. A public key can be generated by a private key. Public key is what encrypts the data and a only a private key can decrypt it.

  2. Encryption and digital signatures. The private key is what grants you access to the funds sent to the public key, which was derived from the private key.

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#4994

  1. If we consider public and private keys like your email address, the private key can be considered as the unique alphanumeric password you create and the public key and bitcoin address is like your email address that you share with the world to send and receive encrypted messages.

  2. What 2 use-cases can public key cryptography be used for?
    Cryptocurrency and public key signing digital documents and encrypted messaging.

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#4995
  1. A Public key is used to except information that is sensitive and the private key Is used to decrypt that sensitive information which was encrypted with the use of the public key
  2. The two methods of use are encryption and digital signatures.
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#4996
  1. Each public key matches to a single private key. Together they can be used for encryption and digital signatures.
  2. Encryption and digital signatures.
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#4997

1 - Private key is the key you keep safe and will use to create your public key. Public key is the key created with your private key and that you can share with others to receive bitcoins
2 - Uses cases are encryption and signature

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#4998
  1. Describe the concept of public and private key with your own words.
    Public-key cryptography uses two mathematically related, but not identical, keys - a public key and a private key. The public key can be used to encrypt a message that A wants to send to B. B can then only decrypt it with his private key. What is also done with PKC is that content is digitally signed with an individual’s private key and is verified by the individual’s public key.
  2. What 2 use-cases can public key cryptography be used for?
    Encryption and digital signatures
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#4999
  1. You can encrypt a message using a public key, and everybody can see this message encrypted, but only you can decrypt it with your private key
  2. Encryption and digital signatures
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#5000

  1. A private key - public key pair is used to send information through a secure and open network. A private key is a random number generated and then a public key is derived from the private key. A public key is used to encrypt a message and a private key will decrypt a message. The public key is shared everywhere and there is no way to derive a private key from a public key.

  2. It can be used for encryption, being able to send information in secret. Another use case is for digital signatures, verifying who sent a particular message or transaction.

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#5001
  1. a) Each wallet is based on private and public key pair
    b) the public key is used to enrypt sensitive information and the private key decrypts the information that was encrypted with the use of the public key.
    c)bitcoin is extremely reliant on “digital signatures” private and public keys
    d) private key (random number) generates a public key (through a special formula) public key is shared on internet for world to see
    e)from private key - formula creates a public key, from public key - bitcoin address, and then you’re in the network - sending and receiving bitcoin, private key safe
  2. sending and receiving bitcoin or message
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#5002

  1. Describe the concept of public and private key with your own words.
    The Private key is secret, it is a random number. After creating a private key, a series of values and hashing can result in a public key. The will be linked, proving a connection of ownership of assets or information connected to tha private key.
    The Public key is for the world to see, no way to get private key. Only 1 way function.

  2. What 2 use-cases can public key cryptography be used for?
    Encriptying and Digital Signatures. In Bitcoin, the Public key is the address you share so other people can send you BTC. The Private key is what grants you acces to the funds sent to the public key. It also represents the sender’s TTX so the receiver can verify teh TTX is valid.

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#5003

  1. I like to describe the concept of Bitcoin address, a public key and private key, in such a way:
    The concept of having your Bitcoin is like having an apartment. The Bitcoin address is like the address of the residence where we can search on Google maps or other apps. The public key is like knowing the residence’s unit number to know where to find it on which floor and which door. The private key is like a key to the door at your unit to unlock it. However, in the case of Bitcoin, losing the private key means that you can derive the unit of residence and the place of residence just through the private key. Some community members used the more technical and mathematical way to describe Bitcoin. The number generated uses two unique prime numbers, which puts things a lot more complex and hard for a human mind to figure out such scale.

  2. Public key can be used to encrypt messages to protect the message/information encrypted.
    In Bitcoin, the public key creates a digital signature from the private key, which generates a Bitcoin address to be used for digital identification purposes to be authenticated by the receiving party.

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#5004

Private key is created at random and is secret only to one individual. A public key is born from a private key and is used to allow others to encrypt a message. Only the private key can decrypt this message

This can be used for secure bitcoin/crypto transactions, send secure information and digital signatures

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#5005

  1. Private keys are used to sign messages validating the authenticity of the sender while public keys are used for receiving messages.

  2. Receiving transactions on the blockchain and receiving encrypted messages .

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#5006

  1. public key is as the name, public, and everyone can see it, private key is your way to verifed and check this “transaccions”

  2. It could be used to encrypt a message and decrypt it. Another is to have access to your coins, that is the reason, to be totally private, your private keys.

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#5007

  1. Public/Private keys - Public key is your wallet address, It is paired with an accompanying private key, which is what gives users access to said wallet and puts them in control of their funds. Your public key signs and verifies transactions, and the private key grants you the ownership of said public key.

  2. Encryption and decryption of messages/transactions. An user sends a transaction, which is encrypted by the recipients public key, which is in turn decrypted by their own private key.

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