Authentication Routines (AQA GCSE Computer Science)

What is authentication?

• Authentication is the process of ensuring that a system is secure by asking the user to complete tasks to prove they are an authorised user of the system
• Authentication is done because bots can submit data in online forms
• Authentication can be done in several ways, these include
  • Usernames and Passwords
  • CAPTCHA
• Other methods that programmers can do to authenticate the user is include
  • Allowing users to recover passwords via email links and SMS codes
  • Encrypting data

Writing authentication routines

• An authentication routine is a method a programmer can use to ensure a user is entering the correct credentials to access a program or system
• The exam requirements are that students only need to be able to write plain text authentication routines and do not need to include encryption 
• The examples below will be written in Python

Example authentication code using an If statement

• This first program is a very simple version and would not be used in a real-world program
• This example demonstrates the fundamentals of how an authentication check would take place

username = input("Enter a username ")
password = input("Enter a password ")
if username == "SaveMyExams" and password == "coding":
    print("Welcome to the program"
else:
    print("Wrong details entered")

Example authentication code using a 2D array

• This second program is a better version which stores the usernames and passwords in a 2 dimensional array
• This example demonstrates how iteration and selection can be used together to store and retrieve information