We are making a great progress towards asymmetric encryption and photography, we have already discussed
about what is cryptography and what is symmetric encryption.
Now, let us move on to the next part of cryptography, which is asymmetric encryption, as the name
suggests.
It's not symmetric, which means there are two keys which are used to encrypt and decrypt the message.
So one key is used to lock your house and different key is used to unlock your house.
So these two keys in asymmetric encryption, Adonis, public and private key, which means that you
can unlock the door, you can lock with public key and you can unlock with private key.
So they are, you know, apair or you can unlock with private key.
Unlock with public key.
So the first option here is you have to encrypt with the public key.
So if that is in a document you want to send over, you have to encrypt it publicly and then you can
decrypt it private key or you can encrypt with the private key and then decrypt with the public to know
which one is more secure over here.
And it's like if Alice wants to send something, both the keys should be of Alice.
You can't encrypted publicly of Bob and then decrypt with private key of Alice.
That doesn't work.
The algorithm is not designed in that way.
Or you cannot encrypt with Bob's private key and then decrypt with Alice's public key.
So what you can do here is you can if you want to send me data, if you want to send me a document,
you can either encrypt with my public key here and then I will decrypt it with my private key.
Or you can encrypt with my private key and then I will decrypt my public key.
So which one is more secure now before that?
Public key is of public knowledge, which means that is a repository and public key is available to
everyone and anyone can access your public key.
For example, if you're using WhatsApp, when you are trying to converse, you can see in your settings
that there's an option, which is this jacket is end to end encrypted, which means that the public
key of you and your friend is stored in the WhatsApp database and the internal application can access
any public but private key is stored to you.
So in a couple of times, I will give you time to think which one is more secure over here.
So these are the examples of asymmetric encryption, the reversed Shamy Adilman.
These three people were outstanding minds.
They developed this algorithm, which is used as asymmetric encryption.
Then as I explained in the last lecture that Diffie Helmund Exchange uses these terms for elliptic curve
cryptography.
It's a very modern cryptography.
It's hugely vague and advanced.
And then we have El-Gamal cryptography along that.
We have the digital signature algorithm nowadays.
You must have heard about this word very often.
This word right here, digital signature.
Every one of us is using digital signature.
So this algorithm is also very common.
Yes.
We are going to talk about this in the coming lecture's.
And as we know, symmetric encryption was known as private encryption or security encryption, but asymmetric
encryption is known as public encryption.
Why it is called public encryption.
Well, this is a hint for you for this problem here.
Why this is called as a public encryption.
We will see in some couple of lectures.
The drawback is that since there is involvement of two different keys and different prime numbers and
generators, asymmetric encryption takes more time than symmetric encryption.
Obviously, you if you have two different keys to unlock and lock the same thing, it will take time.
Right.
But if you have one key, you can do it very quickly.
So asymmetric encryption takes a lot of time as compared to symmetric encryption.
So these are the examples of asymmetric encryption RSA.
It has a key generation that go to them and it has a signature generation and then verification algorithm
in the same way.
Defilement is this formula.
So this formula is very important and is equal to Jedi's to key maad be what are the elements, what
is and what is what is key.
What is B we will be exploring when we have a different lecture on the defilement key exchange algorithm
for time being.
What you need to remember is there are two different keys, just like me.
It is just make some important points.
All right.
So what do you have to remember is you have to take that.
There are two different keys, public and private key decide which one is more beneficial.
You have to remember Oddisee, Diffie, Heldman, BSE.
And the drawback, it is very important.
So these five to six points are very important.
If you want to correct any question when it comes to asymmetric encryption, in the next lecture, we
will be talking about working of asymmetric encryption.
All right.
I will see you in the next lecture.