Homework on Public and Private Keys - Questions

[Tedstar]

1.Public key allows data to be sent securely over a open or unsecured network which can the be opened using the private key to view data or verify sender
2. Encryption and Signiture

[alegarap]

1. A private key is a random number that a computer generates and that is mathematically almost impossible to be the same as another private key generated. From that private key, a public key can be created. You can infer the public key from the private one, but not viceversa.

2. The 2 use cases are encryption and digital signatures.

[CraigH]

• Describe the concept of public and private key with your own words.
  Your private key is used to generate a public key and bitcoin address initially. Its then used as a signature in signing any transactions you’d like to make. The public key and address become your public facing ID in which you can receive transactions from everyone else.

• What 2 use-cases can public key cryptography be used for?
  Sending verified messages or funds in a way that is verified by all users through consensus

[Tose]

Public keys are used for everyone to see, but the message that is sent is encrypted and only the recipient can see the actual message.

Private key is not to be shared with others and holds your digital signature.

[Alko89]

@CraigH

Sending verified messages or funds in a way that is verified by all users through consensus

@k_p

Bitcoin and Altcoin addresses and signatures

Both of these are digital signatures (transactions on bitcoin are basically signed messages). The other use case is encryption

[Alko89]

@Tose

Private key is not to be shared with others and holds your digital signature.

Digital signatures are used for signing messages. You sign the message with your private key and others can verify you are the writer of the message by using the public key.

[Douglas]

Public and private keys are an integral part of cryptography. The public key is what the rest of the word can see and use and the private key should only be known by particular individuals.

Public and private keys can be used for encrypting and decoding messages and verifying the identity of something or someone.

[alesanchez]

1.Private key is unique and generated by the computer, a random number. The public key is generated using the private key. Anyone can see this public key but you can never find the private key from the public key.
2.The two use cases for public key cryptography are encryption and digital signatures.

[Crabheadjams]

1. A private key is generated to hold and protect data on open platforms from outside parties. Only the party with the private key can access a wallet or generate an existing wallet. Also, one must have the private key to sign a digital signature. The public key is generated form the private key. The public key is for everyone to see and use to send you data.

2. Public key cryptography is used for for encryption and to insure others identity through digital signatures.

[CryptoUnicorns]

1. Only 1-way generating from own computer given random number private key to a formula-generated public one to encrypt messages sent through online insecure environment

2. they are used to

• Encrypt - make message to send secret and secure - and to
• sign it digitally. A formula checks in recipient computer the validity of sender signature, if it derivates into the visible public key of the sender.

[CaliCrypto22]

1. Describe the concept of public and private key with your own words.
   A: A private key is a number that is generated randomly by your computer. Then by using a formula, you can generate a public key based on your private key. The public key is what you share everywhere. You keep your private key secret. It is impossible to derive someone’s private key from their public key.

2. What 2 use-cases can public key cryptography be used for?
   A: One use case is sending encrypted messages over a public network (from one person to another). The other use case, which is employed by Bitcoin, is digital signatures.

[Oscar_Ozaine]

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

Public key is generated with the private key and it can only be decoded(signed) when you have access to the private key

Private key is a large number that is only intended for individual to generate public keys

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

They are use to encrypt - decrypt messages or transactions

[SaintRyujin]

1. Private keys are a large sequence of numbers that are computer generated, these are generally kept a secret. Public keys are based off a private key, and then these are shared with the public.

2. The 2 use cases for public key cryptography are for sending encrypted messages between parties. If one party wants to encrypt a message they provide the other party with their public key. That will be used to send the message and the private key will then be used by the 1st party to decrypt the message. The other use case is for verifying digital signatures, this done by using the public key of the sender to verify that their private key signed a transaction, document, message, etc.

[meganova]

1. Describe the concept of public and private key with your own words:
   Public key is shared with others and is used to encrypt data sent to you. The private key is kept safe and secret by you and used to decrypt the data encrypted with the public key.

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

[Kim]

1.First a random private key is generated, from this through a mathematical algorithm a public key will be generated. You can now receive messges with your public key and decrypt them with your private key. Using digital signatures you can use the private key to sign a message. When you open a wallet, your computer creates a private key , from that you create a public key and from that you can create a btc wallet adress.

2. encryption and digital signatures.

[levinardo]

1. Describe the concept of public and private key with your own words.
   In cryptography a person can generate private key randomly, where other things such as public key or address can be derived from it. Both public and private keys can be used to encrypt information, but only public key can make sure someone can identify / decrypt the information cryptographically encrypted using either private/public key. The public key is derived from the private key, but private key cannot be derived / calculated / computed using public key.
2. What 2 use-cases can public key cryptography be used for?
   Public key cryptography can be used in encryption such as in the messaging example, and then also can be used for signing / used as digital signatures.

[Alko89]

@Oscar_Ozaine

They are use to encrypt - decrypt messages or transactions

Transactions are not encrypted in Bitcoin, you digitally sign a transaction

[theRealLos]

1. A private key is a large randomly generated number that is very likely to be unique, i.e. no one else has ever gotten the same number assigned, at least within the same network. From this number and using a mathematical function f(privateKey) a public key is derived, which then can be made known.
2. a) Encryption: Messages can be encrypted using the public key. Then, the owner of the private key from which that public key was derived can use a mathematical procedure akin to the one that generated the key to decrypt the message.
   b) Digital Signatures: In sort of a reverse way, when sending a message an entity can sign it using their private key. The private key won’t be made public, but the signature corresponds to the private key. Then, a second entity receiving the message can use the originator’s public key in conjuction with the signature to verify that it matches the originator’s private key without actually getting to know what that private key is (this was not specifically mention but it has to work that way, right?).

[Kelby_Rodriguez]

1. Describe the concept of public and private key with your own words.
   They both uses cryptography; they are the backbone of the transaction system.
2. What 2 use-cases can public key cryptography be used for?
   Encryption and verification of digital signature

[Eva]

1. Public key is based on the private key. The public key’s function is to allow those checking transactions approved via private key to have a means of ensuring the transaction originated from the source associated with the public key. There is a mathematical means of using the digital signature together with the public key to check this. It is very important to keep the private key information from anyone else as the private key enables the holder to spend the Bitcoins attached to that key.
2. The two use cases for public key cryptography are: 1) Encryption of messages where public view of messages is blocked by applying a formula to the message so the message output is representative characters of the real message rather than an easy-to-read message. The message is digitally signed by the private key of the sender and the receiver uses the sender’s public key together with the digital signature to identify the sender and decrypt the message. 2) Approving Bitcoin transactions whereas the digital signature derived from the private key is deciphered using the public key. The Bitcoin address is used for transactions and is derived from the public key and works as an additional layer for increased security and the privacy of the account holder. The Bitcoin address is secure as there is no way to derive the private key by way of the Bitcoin address.