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Learn about algorithms including programming principles, variables and sequencing. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.1: Programming Principles Exam Board: Eduqas / WJEC Specification: 2020 + Problem Solving There are four stages to computational thinking (smart problem solving ). Decomposition is when you break a problem down into smaller tasks so that it is easier to solve . Pattern Recognition is the process of identifying similar patterns within a problem . Abstraction is when you ignore unnecessary information and focus only on the important facts . Algorithms are the final stage as step-by-step rules are created to solve the problem . An algorithm is usually written as psuedocode or presented as a flowchart . Programming Constructs There are three constructs (ideas) of programming that most programs will contain: Sequence Structuring code into a logical, sequential order . Selection Decision making using if statements . Iteration Repeating code , often using for loops or while loops . Variables Large programs are often modular - split into subroutines with each subroutine having a dedicated purpose. Local variables are declared within a specific subroutine and can only be used within that subroutine . Global variables can be used at any point within the whole program . Local variable advantages Saves memory - only uses memory when that local variable is needed - global variables use memory whether they are used or not. Easier to debug local variables as they can only be changed within one subroutine. You can reuse subroutines with local variables in other programs. Global variable advantages Variables can be used anywhere in the whole program (and in multiple subroutines). Makes maintenance easier as they are only declared once. Can be used for constants - values that remain the same. Local & Global Variables Constants A variable is data that can change in value as a program is being run. A constant is data that does not change in value as the program is run - it is fixed and remains the same. An example of a constant in maths programs is pi - it will constantly remain at 3.14159 and never change. π π Counts & Rogue Values When using iteration (looping) the loop must eventually be able to stop. A count is a variable that is used to record the current iteration (loop number). A rogue value is an unexpected value that will cause the loop to end . For example by typing "Stop" into a loop that asks for numbers. Self-documenting Identifiers An efficient program will use variables with sensible names that immediately state their purpose in the program. Using variable names like 'TotalNum' and 'Profit' rather than 'num1' and 'num2' mean that other programmers will be able to work out the purpose of the code without the need for extensive comments. Q uesto's Q uestions 8.1 - Programming Principles: Problem Solving 1. What is meant by 'decomposition '? Why is it important ? [2 ] 2. What does the term 'abstraction ' mean? Why is it important ? [2 ] 3. What is pattern recognition ? [2 ] 4a. What is an algorithm ? [1 ] 4b. What are the two ways of writing an algorithm ? [2 ] Programming Constructs 1. Describe and draw a diagram for the 3 programming constructs . [6 ] Variables 1. What is the difference between local and global variables ? [4 ] 2. Describe two advantages of using local variables . [2 ] 3. Describe two advantages of using global variables . [2 ] 4. What is a constant ? Give an example . [2 ] 5. Why is it important to use self-documenting identifiers when programming? [2 ] 6. What is a count ? What is a rogue value ? [2 ] 7.1 - Language Levels Theory Topics 8.2 - Understanding Algorithms

Test your understanding of inputs in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 2 Practice Tasks Task One: Food & Colour Ask a user to input their favourite colour and their favourite food and then print a response using both answers. Requirements for a complete program: Use only one print line. Include both of the user's answers in the print line. Include capital letters, full stops and no irregular spacing in the printed line. Remember: Break up variables in a print line by using commas or plus signs between each part of the "sentence" . Example solutions: What is your favourite colour? green What is your favourite food? cheese Yum! I'll have green cheese for dinner tonight! What is your favourite colour? purple What is your favourite food? ice cream Let's have purple ice cream for breakfast! Task Two: Trivia Question Create a program that asks the user to input an answer to a trivia question of your choice then prints the correct answer with their response too. Requirements for a complete program: Only two lines. Include capital letters, full stops and no irregular spacing in the printed line. Example solution: What is the capital city of Botswana? Windhoek Correct answer: Gaborone. Your answer: Windhoek What is the closest planet to Earth? Mars Correct answer: Mars. Your answer: Mars Task Three: Getting to School Create a program that asks the user how they get to school and how many minutes it takes them (using int ). Then print an appropriate response that uses both variables . Requirements for a complete program: Use only one print line. Include both of the user's answers in the print line. Include capital letters, full stops and no irregular spacing in the printed line. Example solution: How do you get to school? car How many minutes does it take you? 45 Really? It takes you 45 minutes to get here by car? How do you get to school? walking How many minutes does it take you? 20 Really? It takes you 20 minutes to get here by walking? ⬅ 2b - Inputting Numbers 3a - Data Types ➡

Learn how to use variables in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 1d - Using Variables Printing Variables Within Sentences Join sentences and variables together using a plus symbol (+ ). Joining strings together like this is called concatenation . name = "Marina" print( "Hello " + name + ", nice to meet you." ) = Hello Marina, nice to meet you. Remember to use speech marks for your printed statements but no speech marks for variable names . You need to use the + symbol before and after each variable. direction = "north" country = "Wales" print ( "Have you been to the " + direction + " of " + country + "?" ) = Have you been to the north of Wales? Commas can be used an alternative to the + symbol but they will automatically add a space . day = "Saturday" print ( "My birthday is on a" + day + "this year." ) print ( "My birthday is on a" , day , "this year." ) = My birthday is on aSaturdaythis year. My birthday is on a Saturday this year. Using Variables Task 1 ( Pizza Toppings) Use a variable named topping1 and another named topping2. Print a sentence that uses both variables names. Example solution: My favourite pizza is ham and mushroom. Printing Number Variables Within Sentences To join strings and number values then you must use a comma as a plus will not work: cookies = 4 print ( "Munch! There's only" , cookies , "left." ) = Munch! There's only 4 cookies left. You need to use a comma before and after each variable. Using Variables Task 2 ( Stars ) Make a variable named stars and set it to a large number. Print a sentence with the stars variable. Example solution: I think there are 827392012 stars in the sky! Using Variables Task 3 ( Age & Month) Use a variable named age and set it to your current age. Make a variable named month and set it to the month you were born. Remember to use speech marks for text , e.g. month = "August" but no speech marks for numbers (your age). Print a sentence that uses both variables names . Example solution: I am 14 and I was born in August. Using f-Strings Another method of using variables within a printed sentence is to use f-strings . Type the letter f before your output and place your variable names in curly brackets - { } Variables of any data type can be used with f-strings. name = "Tony Stark" alias = "Iron Man" print( f"Did you know {name} is actually {alias} ?" ) = Did you know Tony Stark is actually Iron Man? Using Variables Task 4 ( F-Strings) Create and give a value to three variables : movie_name actor year Use an f-string to print a sentence that uses all three variables. Example solution: Did you know that Harry Potter and the Order of the Phoenix stars Daniel Radcliffe and was released in 2007? ⬅ 1c - Creating Variables Sec tion 1 Practice Tasks ➡

Learn about network devices such as a switch, router, modem and NIC. Also learn about internet terms and services including DNS and the Cloud. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.1b: Network Hardware + The Internet Exam Board: OCR Specification: J277 Watch on YouTube : The Internet Network Hardware DNS Servers The Cloud Network Devices When sending data across a network, files are broken down into smaller parts called data packets . Whole files are too large to transfer as one unit so data packets allow data to be transferred across a network quickly . Each packet of data is redirected by routers across networks until it arrives at its destination. Data packets may split up and use alternative routes to reach the destination address. When all the packets have arrived at the destination address the data is reassembled back into the original file. Wireless Access Point A Wireless Access Point provides a link between wireless and wired networks . It creates a wireless local area network that allows WiFi-enabled devices to connect to a wired network. Examples of a wireless access point in a public space could be a WiFi or Bluetooth hotspot , for example a WiFi hotspot in a coffee shop or airport to provide access to the internet. A wireless access point may be a separate device or built into another device such as a router. Router Routers are used to transfer data packets between networks . Routers receive data packets and use the IP address in the packet header to determine the best route to transmit the data. Data is transferred from router to router across the internet towards the destination. A router stores the IP address of each computer connected to it on the network and uses a list called a routing table to calculate the quickest and shortest route to transfer data. Switch A switch is used to connect devices together on a LAN . It receives data packets from a connected node, reads the destination address in the packet header and forwards the data directly to its destination. A switch will generate a list of the MAC addresses of all devices connected to it when it receives data , and must scan for a matching destination address before sending. An alternative to a switch is a hub but a hub is slower and less secure as it forwards a copy of received data to all connected nodes . Network Interface Controller / Card A Network Interface Controller (NIC ) commonly also known as a Network Interface Card is an internal piece of hardware that is required for the computer to connect to a network . The card includes a MAC address which is used when sending data across a LAN . An ethernet cable is plugged into the network card to allow data to be exchanged between the device and a network. A NIC used to be a separate expansion card but is now typically embedded on the motherboar d . Transmission Media Although not technically a device, the communication channel along which data is transferred will affect performance . Three common types of transmission media include: Ethernet cables - used typically on a LAN to transfer data between nodes and hardware such as switches. Examples include Cat5e and Cat6. Fibre Optic cables - very fast but more expensive and fragile cables typically used to send data quickly along a WAN . Data is sent as pulses of light . Coaxial cables - older , slower , copper cables that are not used as much in modern times as they can be affected by electromagnetic interference . The Internet The internet is a global network of interconnected networks . The world wide web (WWW ) is not the same as the internet. It is a way of accessing information , using protocols such as HTTPS to view web pages . Servers provide services on the internet , such as a web server which responds to the web browser (client) request to display a web page . The web server processes the client request to prepare the web page and return it so the web browser can display it to the user . A website must be hosted (stored) on a web server so that it can be accessed by others using the internet . A unique domain name (e.g. csnewbs.com) must be registered with a domain registrar – this is a company that checks the name is valid and not already taken . What is the Internet? DNS Servers A DNS ( Domain Name System ) server stores a list of domain names and a list of corresponding IP addresses where the website is stored. The first thing to understand is that every web page has a domain name that is easy for humans to remember and type in (such as www.csnewbs.com ) as well as a related IP address (such as 65.14.202.32) which is a unique address for the device that the web page is stored on. The steps taken to display a web page: 1. A domain name is typed into the address bar of a browser . 2. A query is sent to the local DNS server for the corresponding IP address of the domain name . www.facebook.com 3. The local DNS server will check if it holds an IP address corresponding to that domain name. If it does it passes the IP address to your browser . 66.220.144.0 4. The browser then connects to the IP address of the server and accesses the web site . If the local DNS server does not hold the IP address then the query is passed to another DNS server at a higher level until the IP address is resolved. If the IP address is found, the address is passed on to DNS servers lower in the hierarchy until it is passed to your local DNS server and then to your browser. Cloud Storage The cloud refers to networks of servers accessed on the internet . Cloud computing is an example of remote service provision . Cloud servers can have different purposes such as running applications , remote processing and storing data . When you store data in 'the cloud', using services such as Google Drive or Dropbox, your data is stored on large servers owned by the hosting company . The hosting company (such as Google) is responsible for keeping the servers running and making your data accessible on the internet . Cloud storage is very convenient as it allows people to work on a file at the same time and it can be accessed from different devices. However, if the internet connection fails , or the servers are attacked then the data could become inaccessible . Cloud Storage Characteristics: ✓ - Huge CAPACITY and you can upgrade your subscription if you need more storage. ✓ / X - Cloud storage is difficult to rank in terms of PORTABILITY , DURABILITY and ACCESS SPEED because it depends on your internet connection. A fast connection would mean that cloud storage is very portable (can be accessed on a smartphone or tablet) but a poor connection would make access difficult . ✓ - Cloud storage is typically free for a certain amount of storage. Users can then buy a subscription to cover their needs - Dropbox allows 2 GB for free or 2 TB for £9.99 a month. Q uesto's Q uestions 3.1b - Network Hardware & Internet: 1a. Explain how a switch works. [ 2 ] 1b. Describe the purpose of a router . [ 2 ] 1c. State what WAP stands for and why it is used . [ 2 ] 1d. State what NIC stands for and why it is required . [ 2 ] 1e. State the differences between the three main types of transmission media . [ 3 ] 2a. State what the internet is and how it is different to the world wide web . [ 2 ] 2b. What is web hosting ? [ 2 ] 3a. What is a DNS server ? [ 2 ] 3b. Describe, using a mix of text and icons / images , how a DNS server is used to display a web page . [5 ] 3c. Describe how a DNS server searches for an IP address if it is not found on the local DNS server . [ 2 ] 4a. Describe what cloud computing is. [ 2 ] 4b. State two advantages and two disadvantages of the cloud . [ 4 ] 3.1a - Network Types & Performance Theory Topics 3.2a - Wired & Wireless Networks

Learn how to handle numbers in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 9b - Number Handling Rounding Numbers The round() command is used to round a value to a certain number of decimal places . Type your variable into the round command brackets, add a comma and state the number of decimal places to round to. Fixed Decimal Places (Currency) The round function will remove any trailing 0s , for example 30.1032 will become 30.1 even if you specified to round to 2 decimal places . Instead, you can use an f -string and write :.2f after a bracketed variable to use exactly 2 decimal places . The number can be changed from 2. books = int ( input ( "How many books would you like to buy? " )) total = books * 3.99 print ( f"The total is £ {total:.2f} - Thanks for your order!" ) How many books would you like to buy? 10 The total is £39.90 - Thanks for your order! How many books would you like to buy? 100 The total is £399.00 - Thanks for your order! Practice Task 1 Ask the user to enter any large number. Ask the user to enter another large number. Divide the two numbers and print the answer to 3 decimal places. Example solution: Using Numbers as Strings The following techniques all require the integer to be converted into a string first using the str command. Just like a string, you can shorten a variable to only display a certain length . Remember that Python starts at zero . You can select a specific digit in the same manner as when selecting characters in a string. If you want to use your variable as an integer again later you would need to convert it from a string to an integer using the int command. Again, reversing a number is the same as reversing a string. You can also use other string handling methods such as .startswith() or .endswith() Practice Task 2 Ask the user to enter a 10 digit number. Select the 2nd and 8th digits and add them together. Print the total. Example solution: ⬅ 9a - String Handling Section 9 Practice Tasks ➡

Test your understanding of working with files in Python, including reading, searching, writing and editing. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Python - Section 10 Practice Tasks Task One Create a file in Python called DaysOfTheWeek.txt. Write the days of the week into the file in a single print line but put each day on a new line. Check the file to see if it has worked. Example solution: Task Two Create a file called Colours.txt. Use a for loop to ask the user to enter 8 different colours. Write each colour onto the same line, with a space between the colours. Close the file and open it again in read mode and print it. Example solution: Task Three Create a file named "Holiday.txt". Ask the user to enter the family name, destination and and number of passengers. Print each family's details on their own line. Bonus: Edit this program to add a search feature to look for the family name. Example solution: Task Four Use the holiday file from task three above. You are going to change the destination. Ask the user to enter a family name and then a new destination. Update the destination with the new value. Check the file to ensure the destination has been updated successfully. Use section 10c to help you with this task. Example solution: ⬅ 10c - Remove & Edit Lines 11 - Graphical User Interface ➡

About CSNewbs Plus (CSN+) CSN+ is a premium collection of resources made for teachers that follows the Computer Science specifications covered on the website . Currently, these resources are in development , with the Eduqas GCSE resource pack arriving first, based on the Eduqas GCSE Computer Science 2020 specification . < Free zip folder download of all resources for Eduqas GCSE topic 1.1 (The CPU) *Updated Jan 2021* Resources included for each topic: Lesson Slides Starter activity (to print) Task resources (e.g. diagrams or worksheets to print) Task answers What is included in the CSNewbs+ GCSE collection? 39 presentation slides 39 starters 39 task answer documents 19 revision activity pages 7 topic tests & answers See below for more details: + Complete presentation slides for each of the 39 theory topics in the Eduqas GCSE 2020 specification . PowerPoint and Google Slides compatible. Activity resources to print . Including diagrams , tables and worksheets for lesson tasks . All answers included for teachers to use. Starter questions that recap the previous topic. For teachers to print before the lesson. All answers included in the lesson slides. 39 starters . Comprehensive answers for all lesson tasks . 39 task answer documents containing answers for over 100 lesson tasks for teachers to use . Revision templates for students to complete, to print on A3 paper . 19 pages and 7 revision lesson slides . Exercise book headings and the driving question (lesson focus) 7 end-of-topic tests with brand new questions . All answers included for teachers. What is included on the presentation slides? The following breakdown shows the presentation slides for 1.1 (The CPU): A title slide The content covered from the Eduqas GCSE specification Exercise book headings and the driving question (lesson focus) Answers to the starter activity questions Lesson objectives An explanation of the topic Clear explanations of the content First task. Students use slides or CSNewbs to complete. All answers on separate teacher document. Task 2. Table provided in teacher resource pack to print. Further explanations of the content Further explanations of the content with diagrams. Further explanations of the content with diagrams. Task 3. Answers in the teacher document. Plenary to check the students' understanding of the lesson topics. < Free zip folder download of all resources for Eduqas GCSE topic 1.1 (The CPU) *Updated Jan 2021*

Learn about algorithms including pseudocode and flowcharts. Based on the 2020 Eduqas (WJEC) GCSE specification. 8.2: Understanding Algorithms Exam Board: Eduqas / WJEC Specification: 2020 + What is an algorithm? An algorithm is a set of instructions , presented in a logical sequence . In an exam you may be asked to read and understand an algorithm that has been written. To prove your understanding you may be asked to respond by actions such as listing the outputs of the algorithm, correcting errors or identifying an error within it. Programmers create algorithm designs as a method of planning a program before writing any code. This helps them to consider the potential problems of the program and makes it easier to start creating source code. There are two main methods of defining algorithms : Defining Algorithms - Pseudocode & Flowcharts Pseudocode Pseudocode is not a specific programming language but a more general method of describing instructions . It should be unambiguous, and it should not resemble any particular kind of programming language (e.g. Python or Java), so it can theoretically be turned into working code in any language. Generally, pseudocode can be written in any way that is readable and clearly shows its purpose. However, the Eduqas exam board advises that pseudocode for the programming exam should follow the conventions below : Annotation { Write your comment in curly brackets} Define data type price is integer firstname is string Declare a variable's value set price = 100 set firstname = "Marcella" Input / output output "Please enter your first name" input firstname Selection (must have indentation) if firstname = "Steven" then output "Hello" + firstname elif firstname = "Steve" then output "Please use full name" else output "Who are you?" end if Iteration (while loop) while firstname ! = "Steven" output "Guess my name." input firstname repeat Iteration (for loop) for i in range 10 input item next i Define a subroutine Declare Sub1 [Subroutine content indented] End Sub1 Call a subroutine call Sub1 Flowcharts A flowchart can be used to visually represent an algorithm. The flowchart symbols are: Algorithm Examples Below are two different methods for representing the same algorithm - a program to encourage people to buy items cheaply at a supermarket. The program allows the price of items in a supermarket to be entered until the total reaches 100. The total price and the number of items entered are tracked as the program loops. Once the total reaches 100 or more, an if statement checks how many items have been entered and a different message is printed if there are 20 or more items, 30 or more items or less than 20 items. Pseudocode Flowchart {This is a program to see how many items you can buy in a supermarket before you spend over £100} total is integer, itemsentered is integer, itemprice is integer set total = 0 set itemsentered = 0 while total < 100 output "enter the price of the next item" input itemprice total = total + itemprice itemsentered = itemsentered + 1 repeat if itemsentered >= 20 then output "You are on your way to saving money." elif itemsentered => 30 then output "You're a real money saver." else output "Look for better deals next time." end if Reading Algorithms In an exam you may be asked to read an algorithm and prove your understanding , most commonly by listing the outputs . Start from the first line and follow the program line by line , recording the value of variables as you go . When you encounter a for loop , repeat the indented code as many times as stated in the range . Example Algorithm: Start NewProgram i is integer maxvalue is integer input maxvalue for i = 1 to maxvalue output (i * i) ??????? output 'program finished' End NewProgram Example Questions: 1. List the outputs produced by the algorithm if the 'maxvalue' input is 5 . 2. State the code that has been replaced by '???????' and what the code's purpose is. Example Answers: 1. Outputs: 1 4 9 16 25 program finished 2. Missing Code: next i Purpose: Moves the loop to the next iteration. Watch on YouTube Q uesto's Q uestions 8.2 - Understanding Algorithms: 1a. Read the algorithm shown on the left and list all outputs in the correct order if the inputs are 2 for height and 72 for weight . 1b. Give the code that is missing from line 25 . 8.1 - Programming Principles Theory Topics 8.3 - Writing Algorithms

Learn about the five main roles of an operating system including CPU management, security, managing processes and the user interface. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 5.1: Operating Systems Exam Board: OCR Specification: J277 Watch on YouTube : Operating Systems What is an Operating System? An operating system (OS ) is software that helps to manage the resources of a computer system and provide the interface between the user and the computer’s hardware . There are five main functions of an operating system: Memory Management & Multitasking All programs must be temporarily stored in RAM for the CPU to be able to process them. The OS transfers programs in and out of memory from the hard drive (or virtual memory ) when processing is required - programs are removed from RAM when closed to free up space for other tasks. The operating system can only perform one process at a time , but through memory management it can appear that more than one process is being executed - this is called multitasking . Peripherals Management & Drivers A peripheral is an external device connected to a computer system to input or output data . Data is transferred between external devices and the processor and this process needs to be managed by the operating system . A device driver is a program that provides an interface for the OS to interact and communicate with an external device . Drivers are hardware dependent and OS-specific . The driver translates the OS’ instructions into a format the specific hardware can understand . Because the CPU and the peripheral will process data at different speeds , a buffer is typically used to temporarily store data until it can be processed . User Management The OS allows users to create , manage and delete individual accounts . User accounts can be granted different access rights such as an administrator or guest . The OS will manage security settings such as allowing passwords to be reset and can also be used to monitor login activity . File Management The operating system creates and maintains a logical management system to organise files and directories (folders ). File management allows files to be named , renamed , opened , copied , moved , saved , searched for , sorted and deleted . It also allows users to set access rights for specific files and to view file properties . User Interface The final function of an operating system is to provide a user interface , allowing a human to interact with the computer system . The way in which a user can navigate a computer system is known as human-computer interaction ( HCI ). Graphical User Interface (GUI) The most common type of user interface is a graphical user interface (GUI ) which can be presented in the following ways: Icons are displayed to represent shortcuts to applications and files. Multiple windows can be opened at the same time and switched between. A folder and file system is displayed and manipulated allowing for copying , searching , sorting and deleting data. The interface can be customised , such as changing font sizes and the desktop background . The taskbar allows shortcuts to be pinned for quick access . Menus can be opened from the Start button to display files and shortcuts. System settings can be accessed such as network and hardware options . Command-Line Interface Other types of user interface do exist, such as a command-line interface (CLI ). This type of interface is entirely text-based and requires users to interact with the system by typing commands . This is a complicated process and mistakes could easily accidentally delete data. There are many commands to learn so only experts who have been trained t o learn this interface will be able to efficiently make use of it. Other Interfaces Humans can interact with computers using other types of interface , such as: Touch-sensitive interface (e.g. smartphones ). Voice-sensitive interface (e.g. smart speakers ). Menu-driven interface (e.g. ATMs in banks). Q uesto's Q uestions 5.1 - Operating Systems: 1. Describe each role of the operating system : Providing a user interface [ 3 ] Memory management (and multitasking) [ 3 ] Peripheral management (and drivers) [ 3 ] User management [ 3 ] File management [ 3 ] 2. Describe 5 different ways the operating system can provide a graphical user interface (GUI) . [5 ] 4.2 - Preventing Vulnerabilities Theory Topics 5.2 - Utility Software

A list of programming topics including HTML, Greenfoot, Python. All Programming Topics Python HTML Greenfoot Assembly Language App Inventor 2

Learn about network forensics, penetration tests and methods of protection including anti-malware, firewalls, encryption and two-factor authentication. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.9: Protection Against Threats Exam Board: Eduqas / WJEC Specification: 2020 + Network Forensics & Penetration Testing What is network forensics? Network forensics is the monitoring of a network to identify unauthorised intrusions . Network forensics is used to record and analyse attacks on a network and to gather other information about how the network is performing. It is important for organisations to identify weaknesses in their networks so that they can fix them and be prepared for any type of attack or malware. Footprinting - Footprinting is one method of evaluating a network’s security . This is when a security team puts itself in the attacker’s shoes by obtaining all publicly available information about the organisation and its network . Footprinting allows the company to discover how much detail a potential attacker could find out about a system. The company can then limit the technical information about its systems that is publicly available . Penetration Tests Penetration tests are carried out as part of ethical hacking. Ethical hacking is when an organisation gives permission to specific 'good ' hackers to try and attack a system so that the weak points can be highlighted and then fixed. The purpose of a penetration test is to review the system's security to find any risks or weaknesses and to fix them . There are four main types of penetration tests : Internal tests are to see how much damage could be done by somebody within the company with a registered account. External tests are for white hat hackers to try and infiltrate a system from outside the company . Blind tests are done with no inside information , to simulate what a real attacker would have to do to infiltrate the system. + Targeted tests are conducted by the company's IT department and the penetration team cooperating together to find faults in the system. Anti-Malware & Firewalls Anti-Malware Software Anti-malware software is used to locate and delete malware, like viruses, on a computer system. The software scans each file on the computer and compares it against a database of known malware . Files with similar features to malware in the database are identified and deleted . There are thousands of known malware, but new forms are created each day by attackers, so anti-malware software must be regularly updated to keep systems secure. Other roles of anti-malware software: Checking all incoming and outgoing emails and their attachments . Checking files as they are downloaded . Scanning the hard drive for viruses and deleting them . Firewall A firewall manages incoming and outgoing network traffic . Each data packet is processed to check whether it should be given access to the network by examining the source and destination address . Unexpected data packets will be filtered out and not accepted to the network. Other roles of a firewall include: Blocking access to insecure / malicious web sites . Blocking certain programs from accessing the internet . Blocking unexpected / unauthorised downloads . Preventing specific users on a network accessing certain files . Other Methods of Protection Double Authentication Also known as two-factor authentication (2FA ), this is a method of confirming someone's identity by requiring two forms of authorisation , such as a password and a pin code sent to a mobile. 4392 Secure Passwords Usernames must be matched with a secure password to minimise the chances of unauthorised users accessing a system. Passwords should contain a mix of uppercase and lowercase letters , punctuation and numbers . Passwords should be of a substantial length (at least 8 characters) and should be regularly changed . ******** User Access Levels Access levels are used to only allow certain users to access and edit particular files. ' Read-Only ' access is when a user can only view a file and is not allowed to change any data . For example, a teacher might set homework instructions as read-only for students to view. ' Read and Write ' access allows a user to read and edit the data in a file. For example, a teacher might set an online workbook as read and write access for students to fill in. It is important to set access levels so that only authorised users can view and change data. The more users who have access to a file, the more likely it is to be compromised. Certain users may also have no access to a file - when they can't view or edit it. Encryption Encryption is the process of scrambling data into an unreadable format so that attackers cannot understand it if intercepted during transmission. The original data (known as plaintext ) is converted to scrambled ciphertext using an encryption key . Only at the correct destination will the encryption key be used to convert the ciphertext back into plaintext to be understood by the receiving computer. A very simple method of encryption is to use the XOR logical operator . XOR is used on the plaintext and key together to create the ciphertext . Using XOR again on the ciphertext and key will reverse the encryption to reveal the plaintext . Encryption using XOR Plaintext = 00110100 Key = 10100110 XOR Ciphertext = 10010010 Decryption using XOR Ciphertext = 10010010 / Key = 10100110 XOR Plaintext = 00110100 Q uesto's Q uestions 3.9 - Protection Against Threats: 1a. What is network forensics ? Why is it important ? [ 3 ] 1b. Explain what is meant by footprinting and why companies do it . [ 2 ] 2. What is an ethical hacker ? [2 ] 3a. Describe the purpose of penetration tests . [2 ] 3b. Describe each type of penetration test . [ 8 ] 4. Describe the purpose of anti-malware software and its different roles . [ 4 ] 5. Describe the purpose of a firewall and its different roles . [ 4 ] 6a. Describe double authentication . [2 ] 6b. State three rules for choosing a strong password . [ 3 ] 7. Describe the three types of access level . [6 ] 8a. Describe the purpose of encryption . [ 2 ] 8b. Explain how encryption works, using the terms plaintext , key and ciphertext . [ 4 ] 3.8 - Cyber Threats Theory Topics 4.1 - Number Systems

Test your ability to create a more complex program in Python based on a given scenario. Perfect for students learning GCSE Computer Science in UK schools. Extended Task 2 Lottery 17 8 4 13 20 Create a program to simulate a lottery draw. First, create an appropriate print line to welcome the user to your lottery draw. Then let the user enter five numbers between 1 and 20. Next, randomise five numbers between 1 and 20. Check to see how many numbers match and output an appropriate response for each scenario (e.g. “You have not matched any numbers, better luck next time!”) Once you have made the base program implement subroutines and lists . Make it as efficient as possible and professional-looking. Use pauses to reveal each number one at a time like a real lottery draw to build suspense. For this task, you will need to create a document and include the following sections (with screenshots where appropriate): An introduction to explain the Purpose of your program . A List of Requirements for a successful program. Screenshots of your code (with comments in your code to show understanding). Testing – Create a plan to show how you will test your program and then explanations of any errors that you found and how they were fixed . An Evaluation of what worked, what didn’t, and how you met each of your requirements from your original list. Also, discuss further improvements that you could have made to improve your program. Example solution: Helpful reminders for this task: Inputting Numbers Random Numbers Logical Operators Subroutines ⬅ Extended Task 1 (Pork Pies) Extended Task 3 (Blackjack) ➡