Have you heard of the term “Digital Signatures”? What about “Public or Private Keys”? Confused as hell when it comes to this technical mumbo-jumbo?
So what is it?
Digital Signatures are a way to digitally sign (no pen and paper here) and secure messages, documents or transactions.
It’s used as a fundamental element in Blockchain and cryptocurrency.
Digital signatures have 3 parts: The public key, private key and the message.
The public key is publicly available to all. It is your forward facing “identity” to the public. Much like a persons name but with many letters and numbers.
The private key is the key that allows you to use the identity.
The message is whatever you want it to be.
Example me, please
You got it.
Say there is a guy named Ron. Ron wants to publish a message and wants the public to know, verifiably, that the message is authentic and coming from him. Ron writes his message, uses his secret key to encrypt and digitally sign that message and then he sends it out.
Ron then publishes his public key so that normal folks can see what he wrote and verify that it came from him. When we use it to decrypt the message we get:
I Love Bitcoin!
Wait…here comes an attacker. Meet, Veronica. Veronica wants to use this technology to publish something against Ron. She wants his job.
Veronica tries to change the message using a fake secret key to say
I Love Banks!
and then publishes the message along with the public key. Evil laughter ensues!
When people go to decrypt it, they get:
Jibberish. That’s what they get.
Since Veronica doesn’t have the correct secret key — she can’t publish something on Ron’s behalf. Digital Signatures are important because they increase the security of messages.
The best thing? Ron could just as easily use this technology to publish an anonymous message somewhere. The publisher doesn’t have to tie this to their actual identity.