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  • 1.2 - Storage Media | Unit 2 | OCR Cambridge Technicals | CSNewbs

    1.2 - Storage Media Exam Board: OCR Specification: 2016 - Unit 2 Data can be stored on a variety of storage media , each with its own benefits and drawbacks . Magnetic Storage Optical Storage A magnetic hard disk drive (HDD ) is the most common form of secondary storage within desktop computers. A read/write head moves nanometres above the disk platter and uses the magnetic field of the platter to read or edit data. Hard disk drives can also be external and connected through a USB port . An obsolete (no longer used) type of magnetic storage is a floppy disk but these have been replaced by solid state devices such as USB sticks which are much faster and have a much higher capacity. Another type of magnetic storage that is still used is magnetic tape . Magnetic tape has a high storage capacity but data has to be accessed in order (serial access ) so it is generally only used by companies to back up or archive large amounts of data . Optical storage uses a laser to project beams of light onto a spinning disc, allowing it to read data from a CD , DVD or Blu-Ray . ​ This makes optical storage the slowest of the four types of secondary storage. ​ Disc drives are traditionally internal but external disc drives can be bought for devices like laptops. Magnetic Storage Characteristics: ​ ✓ - Large CAPACITY and cheaper per gigabyte than solid state . ​ X - Not DURABLE and not very PORTABLE when powered on because moving it can damage the device. ​ ✓ - Relatively quick ACCESS SPEED but slower than Solid State . ​ Optical Storage Characteristics: ​ X - Low CAPACITY : 700 MB (CD ), 4.7 GB (DVD ), 25 GB (Blu-ray ). X - Not DURABLE because discs are very fragile and can break or scratch easily. ✓ - Discs are thin and very PORTABLE . ​ X - Optical discs have the Slowest ACCESS SPEED . ​ ​ Magnetic Disks are spelled with a k and Optical Discs have a c. Solid State Storage Paper Storage There are no moving parts in solid state storage. SSD s (Solid State Drives ) are replacing magnetic HDDs (Hard DIsk Drives) in modern computers and video game consoles because they are generally quieter , faster and use less power . SSDs can also be external . ​ A USB flash drive ( USB stick ) is another type of solid state storage that is used to transport files easily because of its small size. ​ Memory cards , like the SD card in a digital camera or a Micro SD card in a smartphone , are another example of solid state storage. Paper storage includes printed or hand-written documents, notes, forms, schedules and maps. Paper is relatively inexpensive in small quantities but it can take up a lot of space compared to small devices like USB sticks. Producing paper is environmentally damaging and requires physical security methods to keep safe. ​ Paper, such as a timetable, can be written on if times change and easily carried on a person. However, paper in the form of an essay must be re-printed to add changes . Solid State Characteristics: ​ ✓ - High CAPACITY but more expensive per gigabyte than magnetic . ​ ✓ - Usually DURABLE but cheap USB sticks can snap or break . ​ ✓ - The small size of USB sticks and memory cards mean they are very PORTABLE and can fit easily in a bag or pocket. ​ ✓ - Solid State storage has the fastest ACCESS SPEED because they contain no moving parts . Paper Storage Characteristics: ​ X - Low CAPACITY as each page can only hold a certain amount of information. Paper also takes up physical space . ​ X - Poor DURABILITY as paper can easily tear and become damaged in rain. ​ ✓ / X - PORTABILITY varies as single sheets of paper can be easily folded and placed in a pocket. However, large stacks of paper can be difficult and expensive to transport. ​ X - Paper's ACCESS SPEED , in terms of searching for a specific item, is slow , especially if the paper storage has not been organised efficiently . Q uesto's Q uestions 1.2 - Storage Media: ​ 1. State 3 examples of each type of storage media . For example, a CD for optical storage. [3 each ] ​ 2. Compare each type of storage media in terms of capacity , durability , portability and access speed . You may decide to do this as a table or poster. [16 ] ​ 3. Identify the most suitable device (not the media ) and justify its suitability for the following scenarios: a. Backing up a large database at the end of each day. [5 ] b. Keeping a copy of a cleaning schedule for hotel staff. [5 ] c. Making copies of a promotional video to hand out to audience members at a dancing event. [5 ] 1.1 - Holders of Information Topic List 1.3 - Access & Storage Devices

  • 1.5 - WWW Technologies | Unit 2 | OCR Cambridge Technicals | CSNewbs

    1.5 - WWW Technologies Exam Board: OCR Specification: 2016 - Unit 2 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 . ​ There are three types of world wide web technologies : Internet Intranet Extranet The internet i s a global network of interconnected networks . ​ The internet is public and users have open access . ​ ​ Examples of use: Accessing web pages to shop and watch videos . Businesses may use web pages to advertise their products and allow customers to purchase items. An intranet is a private network that is only accessible to authorised users (e.g. members of a business or school). Intranets are private and users have closed access . ​ Examples of use: Because an intranet is a secured online area , schools often use an intranet to log in to that displays information for teachers and students (such as test results or upcoming events ). Businesses might use an intranet for employees to see sales and performance data or for communication because it can be accessed remotely . An extranet is a private network that is accessible using the internet but provides access only to authorised users . ​ Extranets are private and users have shared access . ​ Example of use: Hotel booking companies (like booking.com) use an extranet to allow hotel owners to log in via the internet to access and update their information. Network Characteristics When connecting to WWW technologies there are several characteristics that a user must consider:​ Speed Speed refers to how quickly data can be accessed . For example, an extranet is the slowest network to use because it must be accessed through the internet first. Security Security relates to how likely the data will be kept secure . An intranet is more secure than the internet because only authorised users can log in. Access Levels Access levels , or permissions , refers to who can see what, in terms of data and files . Resources on an intranet can be set so that only certain users can view them. Accessibility This characteristic relates to how available the data is . For example, the internet can be accessed on any network-enabled device, at any time . Q uesto's Q uestions 1.5 - WWW Technologies: ​ 1. Explain the difference between the internet and the world wide web . [2 ] ​ 2. Describe each of the 3 types of WWW technology . You must mention whether they are private or public and what type of access they have. a. Internet b. Intranet c. Extranet [2 each ] ​ 3. Describe at least one example of how each of the 3 types of WWW technology could be used . [6 ] ​ 4. Describe the 3 WWW technologies in terms of each of the 4 network characteristics . You need to think carefully about this; the descriptions under each icon above can help you with certain answers. To start, describe the speed, security, access levels and accessibility of an intranet . [12 each ] 1.4 - Internet Connections Topic List 1.6 - Information Formats

  • Python | CSNewbs

    Pyt hon Follow the instructions in each section and try the practice tasks on every page . At the end of each section are larger problems to solve. ​ Pyt hon Sections 0. Setting up Python Installing and Using Python ​ ​ 1. Printing and Variables a. Printing b. Comments c. Creating Variables d. Using Variables Section 1 Practice Tasks 2. Inputting Data a. Inputting Text b. Inputting Numbers Section 2 Practice Tasks 7. Subroutines a. Procedures b. Functions Section 7 Practice Tasks 8. Lists a. Using Lists b. 2D Lists c. Dictionaries Section 8 Practice Tasks 9. String Handling a. Basic String Handling b. Number Handling Section 9 Practice Tasks 3. Data Types & Calculations a. Data Types b. Simple Calculations Section 3 Practice Tasks 4. Selection a. If Statements b. Mathematical Operators ( & MOD / DIV) c. Logical Operators Section 4 Practice Tasks ​ 5. Importing from Libraries a. Random b. Sleep c. Date & Time d. Colorama e. More Libraries (math) Section 5 Practice Tasks 6. Loops a. For Loops b. While Loops Section 6 Practice Tasks 10. File Handling a. Open & Write to Files b. Read & Search Files c. Remove & Edit Lines Section 10 Practice Tasks 11. User Interfaces ​ a. Graphical User Interface 12. Authentication a. Error Handling ​ Extended Tasks Extended Task 1 (Pork Pies) Extended Task 2 (Lottery) Extended Task 3 (Blackjack) Extended Task 4 (Vet Surgery) Extended Task 5 (Colour Collection) Extended Task 6 (Guess the Word) Extended Task 7 (Guess the Number)

  • 4.1c - Signed Binary & Floating Point | OCR A-Level | CSNewbs

    Exam Board: OCR 4.1c - Signed Binary & Floating Point Specification: A-Level 2015 An instruction set is a list of all the instructions that a CPU can process as part of the FDE cycle . ​ CPUs can have different sets of instructions that they can perform based on their function. The two most common instruction sets are the simpler RISC (Reduced Instruction Set Computer ) and more complicated CISC (Complex Instruction Set Computer ). Instruction Sets This page is still being updated. Graphical Processing Unit What is cache memory? ​ Cache memory is temporary storage for frequently accessed data . ​ Cache memory is very quick to access because it is closer to the CPU than other types of memory like RAM . Multicore & Parallel Systems What is cache memory? ​ Cache memory is temporary storage for frequently accessed data . ​ Cache memory is very quick to access because it is closer to the CPU than other types of memory like RAM . Multicore & Parallel Systems What is cache memory? ​ Cache memory is temporary storage for frequently accessed data . ​ Cache memory is very quick to access because it is closer to the CPU than other types of memory like RAM . Q uesto's Q uestions 4.1c - Signed Binary & Floating Point: ​ 1. What is cache memory ? [ 2 ] ​ 4.1b - Denary, Binary & Hexadecimal Theory Topics 4.1d - Binary Calculations

  • Python | Extended Task 6 | CSNewbs

    Extended Task 6 'Guess the Word' Game Create a Python program similar to the hit New York Times puzzle game Wordle . Allow the user to make guesses to match the randomly chosen hidden word , stopping when they get it correct. You can download a list of 5-letter words on this page. You will need to read in each line of the list and randomly select one - don’t forget to import the random library . ​ Check if each letter of the user’s inputted word is in the randomly selected word . If you are using an IDE like Replit you can use the colorama library and the Fore command to turn the text: ​ Green if the letter is in the correct position . Red if the letter is not in the selected word . Yellow if the letter is in the selected word but not in the correct position . ​ Add your own flair and additional features to your program as an extension, including limiting the number of guesses and recording how many attempts it took to get the correct answer. Download a file of 534 5-letter words: 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. Reminders for this task: You will need a while loop to repeatedly allows the user to enter words until they match the correct word. Section 10 will help you to open, write and r ead from files . Download the file of 5-letter words from the link above. You will need to randomly select a word from the file. The choice command will help. Selection will be necessary to check if each letter in the inputted word matches the letter in the same position in the correct word. String handling is needed to select specific letters in a string. You will need to use .rstrip() on the selected line (word) that you have randomly chosen from the file. This removes any hidden characters that may interfere with checking if it is equal to the inputted word. There are multiple ways to approach this program, and your solution might look different from the example. Break the problem down and focus on one part at a time. Example solution: The word the user enters should be checked , letter by letter , against the letters in the same position in the randomly chosen correct word . ​ Remember that the first letter in a word has the position 0 , not 1. ​ Below is an example of some incomplete code you may wish to use in your solution. ⬅ Extended Task 5 (Colour Collection) Extended Task 7 (Number Game) ➡

  • 3.3 - Network Topology - Eduqas GCSE (2020 spec) | CSNewbs

    3.3: Network Topology Exam Board: Eduqas / WJEC Specification: 2020 + What is a network topology? Network topology refers to layout of computer systems on a network . Devices in a network topology diagram are often called 'nodes' . What are the different types of network topology? Bus Topology The nodes are connected to a bus (a central cable along which all data is transferred across the network). ​ How it works: Data packets are sent along the main cable (sometimes known as the 'backbone') from the source computer to each other system in turn . Each system checks the destination address of the data packets. If the addresses match then the data is accepted otherwise it is passed on to the next system. Terminators are required at both ends of the bus to mark the end of the cable. Advantages: Because of the simple layout, it is easy to attach another system to the main cable without disrupting the whole network . A bus topology is quick to set up once the main cable has been established making it optimal for temporary networks . A bus topology is cost-effective because it usually contains less cabling than other topologies and requires no additional hardware (like a hub or switch). Disadvantages: Poor security as data packets are passed on to each system on the network. Data collisions are likely - this is when two systems attempt to transfer data on the same line at the exact same time. Resending the data wastes time and slows down the network . The main cable will only have a limited length which can become crowded and slows the network speed as more systems are attached. The main cable must also be terminated properly . Ring Topology Computer systems are connected together in a single loop . How it works: Packets are transferred around the ring in one direction , passing from one computer system to the next in a loop . As the packets arrive at each computer system, the computer checks the destination address contained in the data packet to see if it matches its own address. If the addresses match the computer accepts and processes the data packet, otherwise it passes it on to the next system. Advantages: Data collisions are avoided as data packets are transmitted in one direction around the ring. Attaching more systems to a ring topology won't affect the transfer speed (bandwidth ) as much as other layouts like a bus topology because the data is transferred at a consistent speed . Disadvantages: If any system on the network fails then the whole network fails as the loop is broken and data can't be transferred to all systems. To add a new system to a ring topology the network must be temporarily shut down . Star Topology Each computer system is connected to a central device , usually a hub or switch . How it works: Each computer system is connected to the central hub or switch and transfers its data packets there. The hub or switch looks at the destination address and transfers the packets directly to the intended computer. Advantages: A star topology has improved security because data packets are sent directly to and from the hub / switch in the centre and not necessarily all devices like in a bus or ring topology. New systems can be attached directly to the central system so the network doesn't need to be shut down . System failures of attached computers won't usually cause complete network failure. Transfer speeds are generally fast in a star topology as there are minimal network collisions . Disadvantages: Extra hardware (the hub or switch) is required to be purchased, installed and maintained. If the central system (the hub or switch) fails then the whole network will be unusable until the error is fixed. Mesh Topology In a full mesh network, each computer system is connected to every other computer system . There is also a partial mesh network where only some nodes (e.g. a printer) are connected to every other node. ​ How it works: Data packets are transferred to the destination address along the quickest path , travelling from node to node. If a pathway is broken , there are many alternative paths that the packets can take. Advantages: If one cable or system fails then data packets can take an alternative route and still reach the destination address. Because of the large possible number of systems and connections, a mesh topology can usually withstand large amounts of data traffic . New systems can be added to the network without disrupting the entire topology . Disadvantages: Because of the possibly large amount of cables required (especially in a full mesh topology) this network layout can be expensive to install and maintain . Redundant cabling should be avoided - this is when cables are connected between systems that won't ever need to communicate . Q uesto's Q uestions 3.3 - Network Topology: ​ 1. Draw and label diagrams of all four topologies . [12 ] ​ 2a. A school currently uses a bus topology but is considering changing to a ring topology . Describe two advantages and two disadvantages of both topologies. [ 8 ] ​ 2b. An office currently uses a star topology but is considering changing to a mesh topology . Describe two advantages and two disadvantages of both topologies. [ 8 ] 3.2 - Data Packets & Switching Theory Topics 3.4 - Network Hardware & Routing

  • 1.1 - Computational Thinking - OCR GCSE (J277 Spec) | CSNewbs

    1.1: Computational Thinking Exam Board: OCR Specification: J277 There are three key components to computational thinking (smart problem solving): Abstraction is when you ignore unnecessary information and focus only on the important facts . ​ Abstraction is used because it simplifies a problem to make it less complex . This makes it more straightforward to understand the problem and create a solution . Decomposition is when you break a problem down into smaller tasks so that it is easier to solve . ​ Each individual problem can be separately tested and solved . Decomposition also enables different people to work on the different parts of a larger problem that can later be recombined to produce a full solution . Algorithmic thinking is the final stage as logical steps are followed to solve the problem . ​ The problem is broken down using decomposition into smaller problems . The required data and relevant data structures are considered using abstraction . Q uesto's Q uestions 1.1 - Computational Thinking: ​ 1. What does the term 'abstraction ' mean? Why is it important ? [2 ] 2. What is meant by ' decomposition '? Why is it important ? [ 2 ] 3. What is algorithmic thinking ? What does it involve? [3 ] Theory Topics 1.2 - Designing Algorithms

  • 11.1 - Impacts of Technology - Eduqas GCSE (2020 Spec) | CSNewbs

    11.1: Impacts of Technology Exam Board: Eduqas / WJEC Specification: 2020 + What are the issues created by technology? As the use of computers and technological devices continues to rise every year, this increase brings with it a range of different types of issues . Categories of issues described on this page include: ​ Cultural issues Environmental issues Ethical issues Legal & Privacy issues Cultural Issues Culture relates to society and how different parts of the world vary in terms of computer and internet usage . The Digital Divide This term relates to the gap between those people who have access to modern digital technology (such as computers and the internet) and those who have limited access . 'Limited access' could be devices at home or shared devices or having lower-performance (cheaper) computers and low-speed internet connections. ​ The digital divide can be seen in different ways , such as: People in cities vs. People in rural areas . Younger people vs. Elderly people. Developed countries vs. Developing countries. The digital divide is an important ethical issue because digital technologies have led to numerous international benefits including boosted growth , improved product delivery , enhanced communication and increased opportunities . However, this impact is uneven and these positive impacts are mostly occurring in technologically-advanced regions such as North America , Western Europe and Japan . Regions like some nations in Africa and Central Asia have limited digital infrastructure and government instability , leading to poor internet speeds , high costs and limited resources . ​ Discussion Points: What do you think can be done to bridge the digital divide? Whose job is it to bridge the gap? Who will pay for the technology? Changes to Work The internet , the development of new technologies such as cloud storage and increased video communication have transformed the way that many businesses operate across the world. Staff may be able to work from home or access documents collaboratively outside of the traditional workplace, such as cafes or on public transport. ​ Some jobs have moved abroad to save costs, such as help centres for online issues. Tasks can be outsourced to freelancers in other countries where people are content to be paid less for their time and services. For example, some companies will hire temporary web developers from countries such as India to work for them for a lower salary than local workers. ​ Another change to work that technology has brought is the loss of jobs , especially low-skilled jobs such as factory workers that have seen their roles replaced by technology and automation . However, technology has also created millions of new jobs , including installing and maintaining the machines that replace other roles. Environmental Issues Environmental issues concern the natural world and the negative effects of producing , using and discarding computer systems and devices. Energy and Material Consumption In the past 30 years, the number of technological devices has increased astronomically and thousands of new devices are manufactured each day . These devices need to be assembled using a range of materials , including plastics , metals and some rarer elements and need a considerable amount of electrical power to run. Certain systems like web servers and data centres must be powered on all day , every day, which uses a large amount of energy . Pollution and Waste Generating the electricity to power computers creates pollution - an average PC could require up to 50% more energy per year than a fridge. Computers are difficult to recycle and discarded components can lead to land, water and air pollution due to harmful materials , such as lead and mercury , leaking into the environment. ​ Smartphone trends are also negative for the environment as new devices are released yearly , with minor upgrades that people buy to appear fashionable and up-to-date. To lessen the environmental impact, people should reuse and recycle their devices. Ethical Issues Ethics relates to what is considered right or wrong . Often this is subjective - people may have differing opinions on the issue. Drones Uses of drones: Filming and photography for television, movies and special events. Monitoring pollution levels in the atmosphere. Tracking and monitoring wildlife , such as rhino populations in Africa. Disaster zone response , such as searching for survivors following an earthquake. Delivery companies are developing drones to quickly deliver goods across cities. Drones are used by the military to target sites in other countries, such as American soldiers deploying surveillance drones in Syria. ​ Discussion Points: Should you need a licence to buy and fly a drone? Should drones be used to monitor the public? Like flying CCTV? Should drones be used to deliver items? Like Amazon packages? If a drone hits a plane and it crashes, what should the punishment be? A drone is an unmanned aerial vehicle (UAV ) that is remotely operated and can be used for a wide range of purposes. Self-Driving Cars Self-driving cars (also known as autonomous vehicles ) are currently in the development and testing stage with companies like Tesla and Amazon. Benefits of self-driving cars include: In theory, driving will be safer because cars are less likely to make mistakes that humans do and they can’t become distracted or tired . Self-driving cars should be more fuel-efficient because they take the most direct route to destinations and do not get lost. ‘Drivers’ in the car can perform other tasks instead of driving, such as work or planning. Autonomous vehicles could include trucks and vans to automate the delivery and freight industries . Trucks could drive overnight to deliver goods whereas currently, human drivers must take breaks every few hours. Drawbacks of self-driving cars include: Cars could still crash as code and software processes may fail. The technology is still in development and will be very expensive for the first few years when self-driving cars are available to purchase. Jobs may be lost such as delivery and truck drivers whose vehicles are equipped with self-driving technology. Other industries like motorway services and hotels may also be affected. ​ Discussion Points: Would you trust a car to drive itself? Who is to blame if a self-driving car crashes? The car maker? The people in the car? The software writers? What should happen to the people whose jobs are taken by self-driving vehicles? Artificial Intelligence Artificial Intelligence (AI ) is the act of computers replacing humans to analyse data and make decisions . In recent years AI has become more common in the home and on devices like smartphones; assistants such as Siri and Alexa are prime examples of modern home AI. The weather today is cloudy. Benefits of AI include: Processes are sped up as computers can analyse large amounts of data much quicker than a human. AI can be used when a human is unavailable , such as using a symptom checker on the internet for a minor illness rather than booking and waiting for a doctor. Repetitive or time-consuming tasks can instead be completed by a computer , such as searching and sorting scientific data. Drawbacks of AI include: AI can store and process a lot of personal data , especially personal assistants like Alexa which are always listening for ‘wake words’. This data can be viewed by the company that develops it and could be hacked by attackers. AI is programmed by humans and mistakes in code could have disastrous consequences if the AI is used to make important decisions , such as military deployment. ​ Discussion Points: If a robot harms a human who is to blame? The robot? The programmer? The manufacturer? Us? Would you trust a walking, talking robot assistant in your home? Should AI make decisions for us? Legal & Privacy Issues Legal and privacy issues regard laws that have been introduced by the UK government to protect data, systems and networks from unauthorised access . See 11.2 for explanations about important computing legislation in the UK. Loss of Privacy & Hacking There has been a lot of criticism in the last few years about how internet companies and governments are using personal data to invade privacy and track civilians . Facebook was involved in a scandal with using personal data for reasons that were not the original intention. In reverse, WhatsApp and Apple have been criticised for encrypting messages sent by terrorists that police have been unable to track and read. Every week a new company seems to announce that its data has been hacked . Attackers are constantly using botnets and infected systems to crack poorly secured databases and attempting to phish individuals for usernames and passwords. In the past few years, major hacking breaches include Sony, Yahoo and TalkTalk. ​ Discussion Points: Should the UK government be able to see the websites you have visited in the last year? What should happen if a major company is hacked and bank details are stolen? Should they be fined? Pay customers? Prison? Should WhatsApp allow authorities to access encrypted messages? What if they know a terrorist is using it to communicate? Should the UK debate privacy laws before they go into place? Online Crime Unlawfully obtaining personal information and using it for identity theft or fraud . Harassment and threatening others on social media or private messages; blackmail . Cyber attacks are more common - see 3.8 for information about DOS attacks , IP spoofing , SQL injection and more. Sharing copyrighted material such as television programmes, music and video games. Distributing prohibited material such as drugs or weapons on the dark web. ​ See 11.2 for explanations about different laws that have been created to tackle online crime . The increased popularity of the internet and the rising number of users has led to a wave of online crime , taking many different forms, including:​ Q uesto's Q uestions 11.1 - Impacts of Technology: ​ Cultural Impacts 1a. What is the digital divide ? [ 2 ] 1b. Describe 2 examples of how the digital divide can be seen . [ 2 ] ​ 2. Describe in detail 3 ways that technology has changed the way people work . [9 ] ​ Environmental Impacts 1. Describe the different ways that the increasing use of technology negatively impacts the environment . [ 5 ] ​ Ethical Impacts 1a. What is a drone ? [1 ] 1b. Make a list of all of the positive impacts and the negative impacts of using drones . You should have at least 3 on each side. [ 6 ] ​ 2. Describe 2 benefits of using self-driving cars and 2 negative consequences . [4 ] ​ 3. Describe how artificial intelligence can be used for good . [ 2 ] ​ Legal & Privacy Impacts 1. A hack on a bank has occurred. Describe what you think the impacts would be on the following groups of people: a. The customers . b. The bank managers . c. The general public . [ 6 ] ​ 2. Describe 4 different types of online crime . [ 8 ] 10.3 - Programming Errors Theory Topics 11.2 - Legislation

  • OCR CTech IT | Unit 1 | 5.3 - Threats | CSNewbs

    5.3 - Threats Exam Board: OCR Specification: 2016 - Unit 1 What are the 7 threats to computer systems? Phishing Misleading individuals or organisations into giving up sensitive information (such as passwords or bank details), often through the use of emails . Hacking Exploiting weaknesses in a system or network to create, view, modify or delete files without permission. Similar to data theft - illegally removing copies of personal or company data from computer systems. :( Trojan Appears to be a useful or well-known program but when downloaded and installed it secretly gives the attacker a ' backdoor ' to your system. Through this backdoor the attacker can access data without the user knowing. Football 2020 FREE Interception Data packets on a network are intercepted by a third party (e.g. hacker) and copied, edited or transferred to a different location than the intended destination. Eavesdropping Intercepting , in real-time , private communication traffic such as instant messages or video calls . Social Engineering Tricking individuals into giving sensitive information , e.g. by claiming to be from the IT department and asking for their password and username to check for viruses. Virus A virus can replicate itself and spread from system to system by attaching itself to infected files that are then downloaded and opened. Once activated, a virus can modify data or corrupt a system so that it stops working. Q uesto's Q uestions 5.3 - Threats: ​ 1. An IT company is making an information booklet about the different types of online threats . Describe each type of threat: a. Phishing b. Hacking / Data Theft c. Trojan d. Interception e. Eavesdropping f. Social Engineering g. Virus [2 each ] 5.2 - Operational Issues Topic List 5.4 - Physical Security

  • 3.7 - The Internet - Eduqas GCSE (2020 spec) | CSNewbs

    3.7: The Internet Exam Board: Eduqas / WJEC Specification: 2020 + What is 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 . What is a web browser? A web browser is software that uses the HTTP or HTTPS protocol to access and display web pages . ​ Popular web browsers include Google Chrome , Mozilla Firefox and Microsoft Edge . What is a URL? URL stands for Uniform Resource Locator . ​ Web pages are accessed by typing a URL (a web address) into the address bar of a web browser . The URL is the complete address that matches an IP address where the website is stored. ​ We use URLs because they are easier to remember than IP addresses, for example, 'twitter.com' is simpler than '199.59.149.165'. What is the structure of a URL? A URL is structured into different segments: What is a DNS Server? ​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. The browser checks a local (cached) host file to check if it already holds the IP address, but if it doesn't... 3. A query is sent to the local DNS server for the corresponding IP address of the domain name . www.facebook.com 4. 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 5. 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. Q uesto's Q uestions 3.7 - The Internet: ​ 1a. Describe the difference between the internet and the world wide web ( WWW ). [ 2 ] 1b. What is the purpose of a web browser ? [ 2 ] 1c. Why do humans use URLs instead of IP addresses? [ 1 ] 1d. Write out the following URL and label each section: https://www.skynews.co.uk/worldnews/ukstockmarket [ 6 ] ​ 2a. What is a DNS server ? [ 2 ] 2b. Describe, using a mix of text and icons / images , how a DNS server is used to display a web page . [5 ] 2c. Describe how a DNS server searches for an IP address if it is not found on the local DNS server . [ 2 ] 3.6 - 7-Layer OSI Model Theory Topics 3.8 - Cyber Threats

  • 2.1 - Logical Operators - Eduqas GCSE (2020 spec) | CSNewbs

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