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In the last video, you might have heard the term of digital signatures and certificates.

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This video we are going to learn about digital signatures and where are they used and what is the importance

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also?

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We will have a long discussion on the digital signature process so that you can understand the concept

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clearly.

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Let's start digital signatures like electronic fingerprints in the form of a coded message, the digital

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signature securely as a sign of the document in a recorded transaction.

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Digital signatures use a standard accepted format called public infrastructure, which we have already

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seen in the last video, B.K. is used to provide the highest levels of security and universal acceptance.

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They are a specific signature technology and implementation of electronic signatures that is e-signature.

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So in technical terms, a digital signature is a mathematical scheme for verifying the authenticity

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of a digital message.

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They are symmetric cryptography to simulate the security properties of a signature in the detail rather

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than in return for.

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Now, you have already heard of the term electronic signatures, so what is the difference between a

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digital signature and an electronic signature?

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The broad category of electronic signatures encompasses many types of electronic signatures.

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The category includes digital signatures, which are a specific technology implementation of electronic

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signatures.

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Both digital signatures and other signature solutions allow you to sign documents and authenticate the

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sign.

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However, there are differences in purpose, technical implementation, geographical use and legal and

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cultural acceptance of these signatures.

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In particular, the use of a digital signature technology for signatures varies significantly between

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countries that follow up on technology like the United States, United Kingdom, Canada and Australia.

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In the European Union, Southern America and Asia, these techniques are also.

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In addition, some industries also support specific standards that are based on digital signatures.

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Now, what is the use of a digital signature?

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Why can't you just go and sign the document?

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Well, if Bob or your friend is in the United States and you are in India, it would cost around one

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and a half left to go there and just sign the document.

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So digital signatures are used to send and receive encrypted emails that are digitally signed and secure,

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they carry out online secure transactions and they can identify participants online transaction.

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Digital signatures makes use of one of the most important elements of information security, of non

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repudiation.

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If you have digitally signed a document, you later cannot deny that you haven't signed the document.

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So digital signatures are used to sign and validate what documents excel in PDF format and everything.

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Digital signatures are a convenient way to authenticate an identity.

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It also provides high level of security for online transactions.

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Digital signatures are used to verify the identity of the sender of the message.

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Like I said, one cannot deny having digitally signed a document.

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These are signatures to an important role for designing and signing contracts of big Elution's.

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Digital signatures remain unchanged throughout the communication or documentation, and they're easily

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transportable and cannot be imitated by anyone else.

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Now, the most important thing is you have learned the theory part of digital signatures, so to get

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authority and get.

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It's time to actually see the process of digital signature.

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Well, how do digital signatures work, as you can see on your screen?

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This is a long process.

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Let's start exploring it by one.

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By one.

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Digital signatures, like handwritten signatures are unique to each sign digital signature solution

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providers such as DocuSign, for example, follow a specific protocol Patika that is public, the infrastructure.

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Bikaner requires the provider to use a mathematical algorithm to generate too long no call, Keith.

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We have seen keys in the cryptography introduction videos.

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One is the public key and another is a private.

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So when a sign electronically signs a document, the signature is created using the sign of priority,

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which is always securely kept by the sign.

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So suppose you are signing a document that which means that you are creating a document using your own

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private key.

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The mathematical algorithm acts like a cipher, creating data matching the signed document called Hash,

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and then it encrypts the results.

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Encrypted data is called as the digital signature.

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Signature is also marked with the time that the document was signed, so the document changes after

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signing the digital signature is Invalides.

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So let's take an example.

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Jeanne signed an agreement to set time-Share using her private.

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The buyer receives the document, the buyer who receives the document also receives a copy of Jean's

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public.

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Now, you may ask, these should be private.

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Well, well, well, public keys are of public knowledge and private key is only restricted to you.

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If the public can't decree the signature means that the signature is in jeans or has been changed since

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it was signed.

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So to me, in simple terms, Jean signs a certificate or a document with her private key, and if you

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are not able to decrypt it with hers publicly, then there's a problem.

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So to protect the integrity of the signature public infrastructure requires that the keys that are created

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and conducted should be saved and transported properly.

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In Reliable Men, digital signature providers like DocuSign or any other vendors you can take, meet

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the public key infrastructure requirements for digital sign.

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So as you can see on the screen, let's consider.

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There's a data that data goes to the harshing algorithm.

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Now, the output of the hash is encrypted, the sign ups priority and that entire thing is known as

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digitally signed document that is digital signature, not that digital sign document is sent over the

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Internet to the vendor to verify, verify, get the digital design document verifiable, applies the

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description of the key and gets the hash hidden.

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Applies hash algorithm, which is equal and therefore signature is validated when hash values are equal.

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Now, which Heschel used to compute in the upper figure, you can see this, a private key encryption,

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that hash value must be equal to the hash value that is obtained after decrypting.

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So this was a long lecture in the next lecture.

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We'll see what a transport layer security.
