By Nesir Muradov
On Feb 08, 2021
A digital signature is a cryptographic signature that the algorithm calculates from the information that the sender sends and the private or secret key that the sender has. The Digital era requires digital solutions to every aspect of our lives, and some novel ideas are adopted by the users quickly. This breakthrough in science will be useful in different situations in daily life.
The digital signature is one of the efficient tool invented by the community, and this has application in the cryptocurrency world, too. We had briefly explained digital signature in previous blogs because it is one of the essential parts of digital security. Digital signatures have indispensable features that make their usage in cryptocurrency. The security of the sender and the information is necessary, and a digital signature solved this. Now, move on to the details of the digital signature.
Digital signing works similar to the real-life signature. There have to be two or more parties, and you have to possess your signature. You sign the paper if you agree with the terms with another party, and no one can force you to do that. Your sign is original, and no one has the right to copy it and sign agreements behind your back.
If we move to the digital world, things are getting interesting. Here everyone has two keys or two signatures. One is a private or secret key and a public key. Let’s simplify the situation and have two parties. You are the sender of the information, and the Coinsfera is the receiver or verifier. There is a document that has to be signed by you. Firstly, you have to digest this document with the help of some algorithm and get your hash value of the data. Then you encrypt the hash file with your secret key. The next step is sending this signed file to the public address of the Coinsfera.
Coinsfera has the original document and the file sent by you. Initially, Coinsfera decrypts the file you sent with your public key. Remember that only your public key can decrypt the file that is encrypted by your private key. So, after decryption, Coinsfera gets the hash value of the file you sent. Next, it is time to get the hash value of the original file to be sure that you signed the same file. If you get the same hash value, then it means that data has not changed. However, if you get the different hash values, it means that data somehow changed or the public and private keys do not match up.
As you can see from the process, it is almost impossible to fake the document or the signature.
Digital signature has some features that cannot be duplicated by other means. Authentication, integrity, and non-repudiation are essential advantages of the digital signature.
The sender encrypts the file with a private key, and the receiver has to decrypt it with the public key of the sender. Since the only public key of the sender can decrypt the corresponding private key, then we can be sure that the appropriate person signed the file.
If the sender sent the message, then he cannot deny that he signed and sent it. If the public key of the sender can decrypt the file, then it has to be signed by the owner of the private key.
If private key signs the original file, no one or nothing can change it. If that file changed, then its hash value will differ, and also product after signing with the private key will be different. So with that feature, the integrity of the file has been assured.
In this blog, we signified the importance of digital signatures. As you can infer, digital signing will be prevalent in the future. It seems like the only way out from forgery or falsification of documents in the digital world is signing digitally. Getting knowledge in this topic can help you deal with similar issues in the future.