Digital Signature- Protecting your secret messages

Introduction

Let use something cliche like in the movies; Now Imagine for a second that you're a secret agent, tasked with sending an ultra-confidential message across the vast landscape of the internet. You've got a vital mission, but you know that there are sly cyber villains out there who would love nothing more than to intercept your message, tamper with it, or even impersonate you. What can you do to avoid this? The answer is simple, just have a digital signature

Now, a digital signature is like a digital fingerprint for your message, a way to ensure that it hasn't been messed with in transit and that it genuinely came from you. It's basically the guardian of data integrity and sender authenticity in the digital world.

^{Image by Gerd Altmann from Pixabay}

The Magic of Hashing

Let's pull back and talk about hashing.

You see, think of hashing as the process that turns your message into a unique secret code. This code is a fixed-size string of characters, often called a "hash value" or "message digest." Even the slightest change in your message will result in an entirely different hash value. It's like having a digital seal that can detect any tampering attempts.

Let's paint a scenario here, let say you have a cherished family recipe (your message), and you want to ensure that nobody messes with it. So, you use a authentic recipe converter (the hash function) that turns your recipe into a unique, secret code (the hash value). If anyone tries to add or remove an ingredient from your recipe, the secret code will no longer match, and you'll know that something fishy is going on in the kitchen!

The mystery called Private Key

Now, let's add an element of intrigue. You have something called a "private key." similar to those we have for our accounts on Hive. Think of it as the key to a treasure chest that only you know about. It's so top-secret that you don't even share it with your closest confidants.

This private key is a part of a pair of keys – a "cryptographic key pair." The other half of this dynamic duo is the "public key." While your private key is for your eyes only, your public key is shared with the world, like a business card that says, "Hey, it's me!"

Now finally, Digital Signature

Now, let's put on our magician's hat and unveil the grand finale. You've got your secret code (the hash) and your private key. Here's where the real magic happens.

You take your secret code (the hash) and lock it up with your private key, using a process called "private key encryption." It's like putting your secret code inside a well-sealed or guarded box, and only your private key can unlock it. This locked-up secret code, along with your original message, forms the digital signature. It's like a fancy seal you put on your letter, but a million times more secure!

The Process of Verification

^{Image by Gerd Altmann from Pixabay}

Now, your buddy on the other side of the digital realm receives your message and spots your fancy digital signature. They also happen to know your not-so-secret public key (the buddy key).

They use this buddy key to unlock the secret code (the hash) from your digital signature. If the unlocked secret code matches the one they calculate from your message, it's like a digital high-five confirming that your message hasn't been messed with, and it's genuinely from you. Sherlock Holmes would be proud!

The Powers of Digital Signatures

But why go through all this cyber-circus, you ask? Well, digital signatures are like the superguardians of the internet! In a way, they bring a host of powered-up protection to the digital world:

Authentication: They prove beyond a shadow of a doubt that you're the real deal. No more online impostors pretending to be you!

Integrity: If someone even dares to tamper with your message, the digital signature will cry foul play by failing to match the original hash. It's like having an invincible guardian watching over your data.

Non-repudiation: It's like having a digital contract signed in stone. You can't deny you sent the message because only you could have made that fancy signature. It's the ultimate "I told you so" in the digital world.

Tamper Detection: If any cyber villains try to tamper with your message during its perilous journey across the internet, the digital signature will scream, "Sabotage!" and fail the verification test. Your data's safety is its top priority!

So, there you have it, the brief mystery behind digital signatures – where secret codes, private keys, and public key help keep your digital messages safe in a world filled with cyber villain, crime and theft

Thanks for reading , Sayonara 🖐️

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Resources consulted

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• ^{https://support.microsoft.com/en-gb/office/digital-signatures-and-certificates}
• ^{https://www.techtarget.com/searchsecurity/definition/digital-signature}
• https://en.wikipedia.org/wiki/Digital_signature
• ^{https://www.docusign.com/how-it-works/electronic-signature/digital-signature/digital-signature-faq}
• ^{https://www.ibm.com/docs/en/b2badv-communication/1.0.0?topic=overview-digital-signature}
• ^{https://www.zoho.com/sign/how-it-works/electronic-signature/digital-signature.html}
• ^{https://www.simplilearn.com/tutorials/cyber-security-tutorial/what-are-digital-signatures}