Passwords, Privacy and Authentication

Hello students, welcome to Kwickprep. Is your password your name followed by one two three? A computer can guess that in less than a second. Today we will learn what makes a strong password and how password managers work. We will also learn two factor authentication and privacy settings.

First, two key words. Authentication means proving that you really are who you say you are. When you log in with a password, the website authenticates you. Privacy means controlling who can see your personal information. Passwords protect your accounts, and privacy settings protect your information.

Look at these passwords. Password one two three is one of the most common passwords in the world, so it is guessed first. Riya two zero zero nine uses a name and a birth year, which friends can easily guess. The third mixes capital letters, small letters, numbers and symbols. The fourth is a passphrase, four random words joined together, which is long and easy to remember.

So what makes a password strong? Length matters most, so use at least twelve characters. Mix capital letters, small letters, numbers and symbols. Do not use personal details such as your name, birthday or phone number. Do not use common words or patterns like one two three four. And use a different password for every account.

Why is length so powerful? Attackers use programs that try millions of guesses every second. This is called a brute force attack. Every extra character multiplies the number of possible passwords. A short password with symbols can still fall quickly. A long passphrase takes far longer to guess.

But how do you remember a different password for every account? You use a password manager. A password manager is an app that stores all your passwords in an encrypted vault, which means a locked and scrambled store. You remember only one strong master password. It can create strong random passwords for you. It also fills them in automatically, and only on the correct website.

Like every tool, a password manager has pros and cons. On the plus side, every account gets a unique strong password. It also helps against fake websites, because it will not fill a password on a look alike address. On the minus side, if you forget your master password, you may lose access to everything. And the master password itself must be very strong, with two factor authentication switched on.

Now, two factor authentication. There are three kinds of proof, called factors. Something you know, such as a password or pin. Something you have, such as your phone that receives an O T P. Something you are, such as your fingerprint or face. Two factor authentication means using two different kinds of proof together.

Here is how a login with two factor authentication works. First, you enter your username and password. The website checks, is the password wrong? If yes, access is denied. If not, it sends a one time password to your phone, or asks for an authenticator app code. It then checks the code. If the code matches, you are logged in.

Why is two factor authentication so useful? Even if a hacker steals your password, they still need your phone. Payment apps already use this idea, your phone plus your payment pin. Authenticator apps are safer than S M S codes, because S M S can be redirected by fraud. And never share the code with anyone who calls you.

Now, privacy settings on apps. When an app asks for permission, ask yourself, does it really need this? A torch app does not need your contacts or location. Set location to only while using the app, not always. Check your phone's settings every few months and remove permissions you do not need. Delete apps you no longer use.

Social media apps have their own privacy settings. Make your account private, so only approved followers see your posts. Control who can message you, tag you or find you by phone number. Hide your email, phone number and birthday from your profile. Turn off location on posts. And check which other apps are connected to your account.

Some exams ask you to describe a login check as an algorithm. Here is a simple version in pseudocode. The user inputs a password and then the code sent to the phone. The word and means both checks must be true. If the password matches the stored one and the code matches the sent one, it outputs Access granted. Otherwise it outputs Access denied.

Pause and predict. Which login is more secure? A password alone can be stolen by a fake website. A password with an S M S code is safer. A password with an authenticator app is safer still. A long passphrase with a security key is the strongest here, because a security key is a small device that fake websites cannot fool.

Let us revise what we learned today. A strong password is long, mixed and has no personal details. A password manager stores unique passwords behind one master password. Two factor authentication combines two kinds of proof, such as a password and a phone. Give apps only the permissions they need. And keep your social media accounts private.