It is my right choices about your privacy and security you have to have an understanding about encryption.
You don't need to know the hard core mathematics I'll save that for another cause.
I'll give you a crash course now on what is important to know so you can make the right choices about
what cryptosystems to use and understand how encryption can be used to help your security and protect
privacy.
It's not an understatement to say the encryption is absolutely the best tool that we have in our arsenal
to protect others from hackers and trackers.
So what exactly is encryption encryption is a method of transforming readable data called plaintext
into a form that is unreadable which is called ciphertext.
This enables the storage or transmission of data in a form that is only readable and which remains confidential
and private decryption is a method to transform ciphertext back into readable plain text.
And if you do a quick search on Google here
and there you can see the Haseeb CPS which means all the content of the web pages are unreadable to
anyone who can see the day to pass them on the network.
So that means that your Internet service provider or your government maybe they can only see the destination
domain.
So you see this is Google Dakoda UK.
Anybody who's sat between me and Google would only know that I was going to Google they would not know
what I was searching for because this is end to end encryption between my browsers application and the
server to simplify things.
There are two main components of encryption.
You can think about there is the algorithm and there is the key.
So conventionally the algorithm is publicly known and has been scrutinized by many many people in order
to determine if the algorithm is strong and there is the key which is secret and you can think of the
key like a password in that it must be secret.
The algorithm is a bit like a padlock and the key is like a key for that padlock the algorithm and key
combination determines how the plaintext will be jumbled up which is a process of substitution and transposition
of those characters which just means that they move the characters around and they change a character
like a to his ADD.
And if the algorithm or key are weak then the encryption will also be weak.
So let me show you an example.
I want to send the file to a friend Bob but I don't want anyone to read it.
So you need something that can encrypt that file.
I downloaded something that can do that.
And that's when Zipp many people have Wynn's if and I've chosen this deliberately because it's not a
specific tool just for encryption but it enables encryption.
So here we have a file for Bob and if I right click on there when Zip zip file using just an evaluation
version to demo and we can see we have an option here encrypt files if you're not familiar with Zip
is a compression tool.
So it will make the file smaller as I send it packages still into a dot zip file and at the same time
I can choose to encrypt that file.
So if I click on the Encrypt file I look at my options here.
I have the option of 256 bit a s 7:59 Yes.
And legacy Zipp 2.0.
And yes here is a symmetric algorithm which means it uses one key.
So if I click on OK and adds you can give me some warning here then it's going to ask me for the password
and that's going to generate my key.
So yes symmetric encryption algorithm uses just one key.
The password is converted to the key using something called a key creation function.
So that gives is an algorithm of a yes and now a key which is something that is created from our password.
Now you can see one too a bit and you can see 2 5 6 8 2 5 6 is the big lenth or you can consider the
strength of the algorithm.
The higher the number in these algorithms generally the stronger the algorithm but the slower the algorithm
to encrypt and decrypt.
Think about if you had a door and it had many many locks on it it would take you a long time to open
and close the door but it arguably could be more secure because it's got more locks on it.
So again this is the same the higher the bit rate.
The more secure is.
But the long way to encrypt and decrypt the 256 is also the key space which is the number of total possible
different keys that you can have with this encryption algorithm.
Now if you look at this for rotor padlocked in front of you and it has zero 10:9 on each rotor.
Think about how many possible combinations does this have.
Well the answer is ten times ten times ten times ten which is 10000 to go through those manually would
obviously take a long time which is why people could box and they don't try to correct them in this
way.
Yes with two five six bits has one point 1 5 7 9 times 10 to the power of 77 possible keys which is
a number so large there is no word to describe it.
It's a lot.
This means it is very difficult to guess even with very powerful computers doing the guessing what the
key is.
As long as you have used a long and random password to generate a key and people and governments are
trying to create these algorithms all the time we know which are the good ones and we know which are
the bad ones we know which ones are susceptible to being cracked.
And we know which ones are not currently susceptible.
When someone tries to guess what the key is by going through every possible combination.
We call this technique brute forcing or brute force in the key a brute force attack.
You can also do a different type of attack which is called a dictionary attack where you try all the
words in the dictionary against the key.
This is much faster but if the key is in the dictionary the cracking is obviously going to fail and
the last method that is used is a hybrid of the two methods where you take the psychology of human behavior
and combine it with a dictionary and brute force attack.
So an example might be well we know that for example the word monkey is often used in passwords.
It's actually an in the top 10 of words used in passwords.
So we also know that numbers are often added to the end of passwords.
So with that in mind we can use the word monkey from the dictionary and use every sort of number combination
at the end of monkey to see if we can crack the key.
And we're going to talk more on passwords have to set passwords password cracking later on.
So back to wins if and yes here is a symmetric algorithm which means it uses one key.
So if I click on OK and add you give me some warning here and then it's going to ask me for the password
and that's going to generate my key.
So yes symmetric encryption algorithm uses just one key.
Other examples include Des's which is a day of encryption standard trippled there's Blowfish.
Or C for RC 5 or 6 and it still stands for Advanced Encryption Standard.
Now symmetric algorithms are used in most encryption systems you'll be using every day Haiti CPS full
description filing corruption Tor VPN pretty much everything.
And a yes is the common standard for symmetric encryption for maximum protection use where possible
to five six and avoid RC 4 and Dare's if you have the choice yes is fast and currently unbreakable.
So if we enter a strong random password here
and this is telling as we haven't entered want but if we did enter warm then we could send this file
to Bob and we can use any method we chose e-mail for example and even governments militaries people
with lots and lots of resources would find it.
Currently with current computing power impossible to crack encryption and less that password was weak
and will cover in later sections.
What is a strong password what is a weak password depending on the situation.