Homework on Public and Private Keys - Questions

[Technophile]

1. Describe the concept of public and private key with your own words.
   A private key is a string of random numbers and letters that allow someone to generate a public key which is then used to receive messages. The private key allows a user to decrypt an encrypted message, use digital signatures, and spend coins from a wallet. The private key must remain known only to the user, otherwise it is at risk of being accessed by others, but the public key is known to everyone so that they can send messages to the intended recipient.

2. What 2 use-cases can public key cryptography be used for?
   Sending/receiving encrypted messages and using digital signatures

[Ziheng]

1. A private key is a key that is generated by the computer for your personal use, and a public key is derived from the private key, which is accessible to practically anyone.
2. Encryption and Digital Signatures

[Mroman]

1.Public keys are available for everyone to see, you can not do much just by knowing public keys. Private keys are secretly know by the owner, with the private keys you can access to public keys, sign transactions…
2. Public keys use to encrypt or to verify a digital signature

[Angelo_Canesso]

1. A private key is a number that should remain secret. From this number we can calculate the public key. The reverse operation isn’t possible. The public key is available to anybody. the public key is used to encrypt a message and the private one to decrypt the message. So that only the desired person which owns the private key can read the message.

2. Assymetric cryptographie can either be used to encrypt messages, so that only the desired person can read it, or as electronic signature to prove that only the owner of the private key has been able to sign a document

[Crypto_James]

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

A public key is your digital identity which is meant to be shared with the world.
A private key is not meant to be shared. The private key is your secret encrypted identity for you to use to prove you are the one sending a transaction.

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

Public key cryptography can be used for:
A) Sending or receiving money in the form of cryptocurrency.
B) Sending or receiving encrypted messages.

[kenn.eth]

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

Private key is a unique random hash, use in the blockchain ecosystem to sign transactions or decrypt messages. You can use private keys to generate a public key, wich is a public version of this private key but that is not able to decrypt or sign messages.

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

1 - To share public information that can be verified.
2 - To provide a zero knowledge proof

[laclaire]

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

Public and Private keys can be used for encryption and digital signatures. A private key is determined (usually a very large number) and used to generate a public key. The private key can not be derived from the public key. The public key is open to everyone and the private key is held in a secret place. When you send or receive a message you that is encrypted you use your private key and your counterpart can use their public key that you supplied to decrypt it. If you sign a msg with a digital signature (your private key) your counterpart can decode the information using their public key.

1. What 2 use-cases can public key cryptography be used for?
   Encryption of messages and Digital Signature

[Lisalazuli]

1. The private key is a unique numerical number that your computer generates and you must keep it safe and secret as if anyone has access to it they can either decrypt your messages or use money in you wallet. Your computer generates a public key from your private key but this is a one way process, no one can guess your public key from your private. Your private key can generate a digital signature.

2. These are used for encryption and digital signatures. In bitcoin the public key is converted into you public bitcoin wallet address that you can give to others.

[Nile]

1. Public key is derived from a private key. Only private to public generation. Not the other way around. You can send your public key to encrypt something or sign something, and then it can be deciphered using the private key … I think.
2. signatures, and encryption.

[CeesQ]

@ivan

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

a private key is a random number generated by your computer. From this private key your public key is derived.

@ivan

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

1. encryption
2. digital signatures

[HoS]

1. Private key I only know. Public key everybody knows. They Public key is a encrypted hash function of you private key, hence it infeasble to be traced back. The private key only privately confirms transactions back and forward thru your public key.

2. Digital signatures and encryption

[Andrewgaven]

1 Public key allow to encrypt messages, private key allow to decrypt the message generated by the public key.
2 Encrypt message and digital signature.

[Restford]

1. Public key is used by others to encrypt messages to you. The messages is decrypted via the private key from which the public key where derived from. The private key can also be used to sign messages as it is your unique signature.

2. Encrypt messages and generate addresses. Verify the signature of someone’s message.

[Mauro]

@Yir

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

To receive encrypted message and decrypt messages.

Don’t forget about digital signatures as well.

[Mauro]

@Long

a bitcoin address can be generated from your public key.

We get the address by actually hashing the public key. Here are the steps if you want to know more: https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses#How_to_create_Bitcoin_Address

[Mauro]

@Jesus

2. Sending information that can be encrypted and only seen by the person it goes to. Sending value using a secure method that cannot be censored or stopped.

While encryption is one of the use cases of the public cryptography, digital signatures are also very important.

“Digital signature is used in Bitcoin to provide a proof that you own the private key without having to reveal it (so proves that you are authorized to spend the associated funds)”

[Mauro]

@victorcaribe

1. Private and public keys allow people to transfer information or value in a secure, trustworthy and private way even when using open channels using to the power of math.

That is a pretty cool way of saying it.

[Mauro]

@Griz

1, Private and public keys pairs are two large cryptographic numbers.

They are large numbers but they are actually not very large in size. In bitcoin, their size is 32bytes or 256bits.

[Mauro]

@AR.18

A private key is the digital signature used to verify a particular message.

When you digitally sign a transaction in bitcoin using your private key, the miner can verify that you are the owner of that transaction by comparing your digital signature with your public address.

[Mauro]

@bigez

The message sent has to be signed with the public key,

private** Example: Transactions in bitcoin.