Defensive Design

Defensive Design

1. Translators

   • Compilers
     • They translate all of the code at the same time and creates an executable file
   • Interpreters
     • They translate the code one instruction at a time but doesnt create an executable file
   • Assemblers
     • are used to turn assembly language to machine code.

2. Defensive design

   • Input sanitisation
     • Removing any unwanted characters before passing data through the program
   • Input validation
     • Checking if data meets certain criteria before passing into the program
   • sanitisation and validation are often done using WHITELIST and BLACKLIST
     • Whitelist is a list of all data that a program should accept
       • Any data that isnt on this list will be rejected
     • A blacklist is a list of all the data that a program should reject
       • Any data that isnt on this list will be accepted

3. Translators

   • High level language
     • The source code is easy for humans to write but computers need to translate it into machine code
   • Low Level Language
     • The source code is tricky for humans to read and write but easier for a computer to run

4. Testing

   • Logic errors
     • When the compiler or interpreter is able to run the program but the program does something unexpected
   • Syntax errors
     • When the compiler or interpreter doesnt understand something you've typed because it doesnt follow the rules or grammar of the programming language

5. Intergrated Development Environments

   • A piece of software that provides features to help a programmer to develop their program
   • The main part of an IDE is a code editor
     • Where the code is written