Symmetric Encryption vs Public Key Encryption – Russell Ballestrini

james-rb 13y, 154d ago

Good to know about the Symmetric Encryption vs Public Key Encryption

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NetEng-rb 12y, 27d ago

Looks like you made a typo or Python calculated it wrong:

n(n-1)/2= keys needed

50(50-1)/2= 1,225 symmetric keys needed.

I thought I didn't have the formula correct when I first saw your article, but I double checked it. Thanks for helping me learn that formula even better! ;)

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russell 12y, 26d ago

Yeah, it is a typo, the function I provided works. However the formula you give is a better solution because it O(1) instead of O(n) so I'm going to update the blog post with your corrections.

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unverified 7y, 57d ago

I have a question just similar to this one

The company is considering a symmetric key solution for communication between the following subsystems.

There are 3 controller devices which send commands to machines. The controller systems need to be able to communicate with each other.

There are 50 machines to control. The machines do not need to be able to communicate with each other, but need to be able to receive control messages from each of the controllers.

How many separate keys are needed in total to realize this system? How much space for key storage is needed on the controller devices? How much space for key storage is needed on the controlled machines?

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russell 249d, 9h ago

Why should I care?

You should care about the difference between symmetric encryption and public key encryption because they are both important methods used to secure communication and protect sensitive information. Understanding the differences between these two types of encryption can help you make informed decisions when it comes to choosing the right encryption method for your specific needs and ensuring the security of your data.

Symmetric encryption is faster and more efficient, making it suitable for tasks that require a high volume of secure communication, such as file transfers or real-time communication. However, it requires the exchange of a secret key between the communicating parties before they can encrypt and decrypt messages, which can be a security risk if the key is compromised.

Public key encryption, on the other hand, uses a pair of keys – a public key for encrypting messages and a private key for decrypting them. This method eliminates the need for exchanging a secret key and makes it more difficult for an attacker to intercept and decrypt messages. Public key encryption is often used for secure email communication, digital signatures, and other applications where the security of the communication is paramount.

In summary, understanding the differences between symmetric and public key encryption can help you better protect your data, choose the appropriate encryption method for your needs, and make informed decisions about security.

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**Why should I care?**

You should care about the difference between symmetric encryption and public key encryption because they are both important methods used to secure communication and protect sensitive information. Understanding the differences between these two types of encryption can help you make informed decisions when it comes to choosing the right encryption method for your specific needs and ensuring the security of your data.

**Symmetric encryption** is faster and more efficient, making it suitable for tasks that require a high volume of secure communication, such as file transfers or real-time communication. However, it requires the exchange of a secret key between the communicating parties before they can encrypt and decrypt messages, which can be a security risk if the key is compromised.

**Public key encryption**, on the other hand, uses a pair of keys – a public key for encrypting messages and a private key for decrypting them. This method eliminates the need for exchanging a secret key and makes it more difficult for an attacker to intercept and decrypt messages. Public key encryption is often used for secure email communication, digital signatures, and other applications where the security of the communication is paramount.

In summary, understanding the differences between symmetric and public key encryption can help you better protect your data, choose the appropriate encryption method for your needs, and make informed decisions about security.

russell 205d, 9h ago [edited]

You: expalin like I am 10

AI:

Imagine you and your friends want to send secret messages to each other. There are two ways to do this:

Symmetric Encryption: This is like having a special secret code book with lots of different codes. If you and your friends all get the same code book, you can send messages to each other using those codes. But, if someone else finds out your code book, they can also read your messages. To protect messages between you and just one friend, you need many different codes, and you have to share the code book with each friend separately. If you have 10 friends, you'll need 45 codes and you'll have to share the code book 10 times.

Public Key Encryption: This is like having a special lock and key for each friend. You give each friend a public lock (which everyone can see) and a private key (which only your friend can see). Now, when you send a message, you use your friend's public lock, and only your friend can unlock it with their private key. No one else can read your message. If you have 10 friends, you'll need 20 locks and keys in total, and you won't need to share anything secret with your friends before you start sending messages.

In both methods, you need to keep your secret codes or keys safe. Public Key Encryption is often safer because it's harder for someone to pretend to be your friend and read your messages.

remark

You: expalin like I am 10

AI:

Imagine you and your friends want to send secret messages to each other. There are two ways to do this:

**Symmetric Encryption:** This is like having a special secret code book with lots of different codes. If you and your friends all get the same code book, you can send messages to each other using those codes. But, if someone else finds out your code book, they can also read your messages. To protect messages between you and just one friend, you need many different codes, and you have to share the code book with each friend separately. If you have 10 friends, you'll need 45 codes and you'll have to share the code book 10 times.

**Public Key Encryption:** This is like having a special lock and key for each friend. You give each friend a public lock (which everyone can see) and a private key (which only your friend can see). Now, when you send a message, you use your friend's public lock, and only your friend can unlock it with their private key. No one else can read your message. If you have 10 friends, you'll need 20 locks and keys in total, and you won't need to share anything secret with your friends before you start sending messages.

In both methods, you need to keep your secret codes or keys safe. Public Key Encryption is often safer because it's harder for someone to pretend to be your friend and read your messages.