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2.3: Utility Software Exam Board: OCR Specification: 2016 - Unit 1 What is utility software? Utility software are dedicated programs used for the maintenance and organisation of a computer system. Antivirus Software Antivirus software is used to locate and delete viruses on a computer system. The antivirus scans each file on the computer and compares it against a database of known viruses . Files with similar features to viruses in the database are identified and deleted . There are thousands of known viruses but new ones are created each day by attackers so antivirus software must be regularly updated to keep systems secure. Other roles of an antivirus: 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. Defragmentation As files are edited over time they will become fragmented - this is when the file is split into parts that are stored in different locations on the hard disk drive . Files that are fragmented take longer to load and read because of the distance between the fragments of the file. Defragmentation software is used to rearrange the file on the hard disk drive so that all parts are together again in order. Defragmentation improves the speed of accessing data on the hard disk drive. Compression Compression is used to decrease the size of a file . This is beneficial as more files can be stored on a storage device if the size has been reduced. Compressed files can be transferred faster across a network because they are smaller in size . Monitors, Managers & Cleaners 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 . Monitoring network ports . System monitors check the resources of a computer and display how much CPU time and memory current applications are using. Task managers allow a user to close processes and applications if they have stopped responding or if one is using too many resources. Press Ctrl + Alt + Delete on any Windows computer to open Windows Task Manager which is a system monitor and task manager tool. A disk cleaner is used to scan a hard disk drive and remove unused files . This is used to free up space on the hard drive. A disk scanner will scan a hard disc for any errors and attempt to repair them . Backing Up Data A backup is a copy of data that can be used if the original data is corrupted or lost . Backups of all data should be made regularly and stored in an alternative location . Alternatively, imaging (also known as disk cloning ) creates an identical image of a storage drive to be stored in a different location . Q uesto's Q uestions 2.3 - Utility Software: 1. What is the purpose of utility software ? [1 ] 2a. Describe how antivirus software works. [ 2 ] 2b. Describe 3 further roles of antivirus software . [ 3 ] 3a. What is the purpose of a firewall ? [ 2 ] 3b. Describe 3 further roles of a firewall . [ 3 ] 4a. Describe what is meant by defragmentation . [ 2 ] 4b. Explain why defragmentation software is used . [ 2 ] 5. Describe 2 benefits of using compression . [ 2 ] 6a. Explain why system monitor / task management software could be used . [ 2 ] 6b. Explain the purpose of disk cleaners and disk scanners . [ 2 ] 7a. Explain what a backup is and why they are are important. [ 2 ] 7b. Describe what imaging is. [ 2 ] 2.2 - Applications Software Topic List 2.4 - Operating Systems

1.2 Computer Components Exam Board: OCR Specification: 2016 - Unit 1 This page describe the various components inside of computer systems . The first three are necessary in every type of computer: Processor Motherboard Power Supply Unit The main role of a processor is to manage the functions of a computer system by processing data and instructions . The primary processor of each computer system is the Central Processing Unit ( CPU ). A processor is attached to the motherboard using a connection point called a CPU socket . The motherboard is the main circuit board of a computer on which components such as the CPU and ROM are connected . The motherboard contains PCI slots for expansion cards and ports for external devices to be connected . The power supply unit (PSU ) converts electricity from AC (Alternating Current) from the mains power supply to DC (Direct Current) which the computer system can use . The PSU of desktop computers is internal whereas portable devices require an external 'charger '. Memory Computer memory is split into two types - volatile and non-volatile . Volatile storage is temporary (data is lost whenever the power is turned off ). Non-volatile storage saves the data even when not being powered , so it can be accessed when the computer is next on and can be stored long-term . Random Access Memory (RAM) Read-Only Memory (ROM) Cache Memory RAM is volatile (temporary) storage that stores all programs that are currently running . RAM also stores parts of the operating system to be accessed by the CPU. RAM is made up of a large number of storage locations, each can be identified by a unique address . ROM is non-volatile storage that cannot be changed . ROM stores the boot program / BIOS for when the computer is switched on. The BIOS then loads up the operating system to take over managing the computer. Cache memory is volatile (temporary) storage that stores frequently accessed data . It is very quick to access and faster than other types of memory like RAM because it is stored on the processor itself. RAM ( R andom A ccess M emory) ROM ( R ead O nly M emory) Cache Memory Secondary Storage Magnetic Storage Optical Storage 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. 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 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. A magnetic hard disk drive (HDD ) is a 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 . Solid State Storage Cloud Storage When you store data in 'the cloud ', using services such as Google Drive, 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 typically free for a certain amount of storage and users can buy more storage space when they need it - the scalable nature of this storage type makes it very flexible for businesses. 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 is also known as 'virtual storage ' because the data is saved remotely , freeing up physical storage space for users on their own devices . 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 . 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. Solid State Characteristics: X - 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 . 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 . Storage Protocols SCSI ( Small Computer System Interface ) is a protocol (set of rules) for attaching external devices to a computer system, such as a printer, storage drive or scanner. SAS ( Serial Attached SCSI ) is an improved version of SCSI that enables many more external devices (up to 128) to be connected at the same time to a computer system. Expansion Cards Expansion cards are dedicated circuit boards with a specific purpose that are attached to the motherboard . Most of the following expansion cards can also exist as integrated components on the motherboard, rather than a separate card. Graphics Card Sound Card Processes graphical data (e.g. videos or animations) and converts it into a displayable output on a monitor . Network Interface Card (NIC) 0010 1011 0101 0101 0110 0111 0101 0001 0101 Sound cards convert analogue sound waves into digital data (binary) when inputting audio through a microphone. Sound cards also convert digital data (binary) into analogue sound waves to output audio through speakers or headphones. 0010 1011 0101 0101 0110 0111 0101 0001 0101 Allows computers to connect to networks (such as the Internet ) and enables them to transfer data to other computers. Transfers data between servers across a network. Fibre channel allows for quick transfer speeds and is primarily used to connect data storage to servers in large data centres. Fibre Channel Card Storage Controller Card Required for the computer to manage and use any attached storage devices . Ports A port is the interface between external devices and the computer . Ports allow data to be transferred from and to these devices. USB Port Connects storage devices such as USB sticks or external hard drives . Connects input devices such as a keyboard or mouse, as well as other devices for data transfer such as a camera or smartphone. Ethernet Port Connects computers to network devices such as a modem or router, allowing access to the internet . FireWire Port Developed for Apple products, FireWire transfers data at a high speed from devices such as camcorders and external hard drives . FireWire supports isochronous devices , meaning data is sent in a steady , continuous stream . SATA Port Allows fast data transfer to external HDD , SSD or optical drives . SD Port Enables data from an SD card to be transferred from a device like a camera to the computer. Micro SD Port Allows data from a micro SD card to be transferred from devices such as smartphones , tablets and handheld games consoles to a computer. Q uesto's Q uestions 1.2 - Computer Components: Vital Components: 1. Describe the purpose of the following components : a. The CPU (Central Processing Unit ) [2 ] b. The motherboard [2 ] c. The PSU (Power Supply Unit ) [2 ] Primary Memory: 2a. What is the difference between primary and secondary memory ? [2 ] 2b. What is the difference between volatile and non-volatile storage ? [2 ] 2c. For each of the three types of primary memory , describe its role and give an example of what it can store. [6 ] Secondary Storage: 3a. For magnetic , optical and solid-state storage rank these three secondary storage mediums in terms of capacity , durability , portability and speed . [9 ] 3b. For the following scenarios justify which secondary storage medium should be used and why it is the most appropriate : Sending videos and pictures to family in Australia through the post. [3 ] Storing a presentation to take into work. [3 ] Storing project files with other members of a group to work on together. [3 ] Backing up an old computer with thousands of file to a storage device. [3 ] Additional Components: 4a. State the purpose of five different expansion cards . [5 ] 4b. What is the purpose of the motherboard ? [2 ] Ports: 5a. Describe the six different ports . [6 ] 5b. What is the difference between SCSI and SAS ? [2 ] 1.1 - Computer Hardware Topic List 1.3 - Computer System Types

3.2 - Virtualisation Exam Board: OCR Specification: 2016 - Unit 1 What is virtualisation? Virtualisation is the creation of a virtual version of a device , software , operating system or server . These virtual versions can then be run on a different physical computer system , such as a powerful server . There are many different types of virtualisation . Storage virtualisation combines multiple separate storage devices into acting and appearing like a single , central storage system . Using storage virtualisation improves scalability as further devices can join the storage system if more space is required . It also simplifies the management of storage across the network. Server virtualisation allows one physical server to be divided into and host multiple virtual servers , each running separately . Each virtual server operates independently , handling its own operating system and applications . This allows for resources to be used more effectively and improves the scalability and versatility of the physical server . Client Virtualisation (Virtual Clients) Client virtualisation is when several virtual desktops are run on a single server - think back to the hypervisor from 3.1 . A virtual client is a full desktop environment where the processing happens remotely . For example, where an operating system is managed and hosted centrally but displayed locally on a different computer. These are often known as 'dumb clients ' because the server does the processing for it , meaning it can have minimal resources like a slow processor and little memory / storage . General Benefits & Drawbacks of Virtualisation Benefits of virtualisation: Costs are cheaper in the long-term because money is saved by not purchasing multiple physical devices . Money is also saved due to less cabling and lower power consumption . If set up efficiently, it can be used for higher performance at a lower cost - "Do more with less" . Programs can be tested in a secure environment before main-system deployment. Simplified response to recover after a disaster because only the server needs to be fixed. Drawbacks of virtualisation: If not set up efficiently, users could face serious performance issues , as fewer servers do more work. If a single physical system fails , the impact will be greater . Initial set up is complex , requires technical knowledge and can cost a lot. Easier for hackers to take more information at once as the data is stored in the same place. Benefits of client virtualisation: All data is stored in one central location , making backup and disaster planning easier to manage . The whole system can be managed , secured and updated from the server , rather than from each individual system. Hardware costs will be reduced because the virtual clients do not store or process their own data , meaning they can be of a low spec . Users can have multiple virtual machines and log in remotely (from anywhere with internet access ). Drawbacks of client virtualisation: Users will be unable to work if network connectivity is lost . There is a high strain on the server as the virtual clients do not store or process data themselves . An increased load on the server might result in poor performance for each client, especially with multiple connections . As the data is stored in one location , there are security risks of unauthorised access if the server is not adequately protected . Server Virtual Clients Cloud Technology 'The cloud ' is storage that is accessed through a network , primarily the internet. A cloud server is an example of storage virtualisation as data may be stored across multiple physical devices . There are three different types of cloud storage: Private cloud is where a business will have its own data centre that employees can access. This allows for flexible and convenient data storage and gives the business control over data management and security . Users of the private cloud will not usually have to pay individually for access - but the company will need to spend a lot of money on set up and maintenance . Public cloud uses third-party service providers such as Google Drive or DropBox to provide storage over the internet . Public cloud is usually a pay-for-use service , where businesses will pay for specific amounts that they need. Data management and data security is maintained by the cloud provider and the business is dependent on them providing constant access and deploying effective security measures. Hybrid cloud uses a mix of on-site storage (private cloud) and third-party (public cloud) services . Organisations can move workloads between private and public clouds as their specific needs and costs change . A benefit of hybrid cloud is that it gives an organisation greater flexibility and data storage options. As an example, a company could use on-site or private cloud storage to hold sensitive information and third-party, public cloud services to hold less important data . Q uesto's Q uestions 3.2 - Virtualisation: 1. What is the difference between server and storage virtualisation ? [ 2 ] 2a. What is a virtual client ? [ 1 ] 2b. What are the advantages and disadvantages of client virtualisation ? [ 8 ] 3. Explain any further general advantages and disadvantages of using virtualisation , not covered in your answer to 2b. [4 ] 4. Describe the differences between private , public and hybrid cloud storage. [6 ] 3.1 - Server Types Topic List 3.3 - Network Characteristics

2.7 - Protocols Exam Board: OCR Specification: 2016 - Unit 1 What is a protocol? A protocol is a set of rules that allow devices on a network to communicate with each other . Protocols to Transfer Data: TCP / IP / UDP TCP ( Transmission Control Protocol ) breaks data down into small packets to be transferred across a network and reorders them back into the original data at the destination . TCP checks for errors when sending data packets, which makes it slower than UDP for data transfer, but it guarantees that no packets have been lost on the way. IP ( Internet Protocol ) is in charge of routing and addressing data packets to ensure data is transferred across networks to the correct destination . It is also an addressing system - every device on a network is given a unique IP address . TCP and IP are often used together to transfer data across the internet. UDP ( User Data Protocol ) is a faster alternative to TCP for transferring data. It is used where low latency ('low lag') is important, such as online gaming and video chat . However, UDP does not automatically check for errors so packets are more likely to be lost or received out of order . HTTP is a protocol that can be used to transfer web pages on the world wide web so that users can view them in a web browser . All URLs start with either HTTP or HTTPS (e.g. https://www.csnewbs.com ). HTTPS is a more secure version of HTTP that works with another protocol called SSL (Secure Sockets Layer ) to transfer encrypted data . You should see a padlock symbol in the URL bar if your connection to that website is secure. HTTP/HTTPS (Hyper Text Transfer Protocol) FTP (File Transfer Protocol) FTP ( File Transfer Protocol ) is used to transfer files across a network. It is used most often to upload or download files to/from a file server . ICMP ( Internet Control Message Protocol ) collects network status information (such as router errors) and is used for troubleshooting . SNMP ( Simple Network Management Protocol ) is a protocol that records network statistics , such as router usage . Network Management Protocols Email Protocols SMTP ( Simple Mail Transfer Protocol ) is a protocol used to send emails to a mail server and between mail servers . POP ( Post Office Protocol ) is for downloading and storing emails from a mail server. TCP/IP Protocol Stack The TCP/IP protocol stack is a model split into 4 layers . The model is used to visualise the different parts of a network as each of the four layers has a specific role . Splitting a network design into layers is beneficial to programmers as it simplifies design , making it easier to modify and use . Each layer has a certain purpose and is associated with different protocols . 4 Allows humans and software applications to use the network e.g. browsers (HTTP /HTTPS ), email (SMTP / POP ), file transfer (FTP ) and network management (SNMP ) applications. 3 TCP breaks the data down into data packets . This layer makes sure the data is sent and received in the correct order and reordered at the destination without errors. UDP can also be used for faster , but less reliable , data transfer . 2 The network layer is also known as the ' Internet Layer '. IP is responsible for addressing and routing data packets . The optimal route for the data to take is calculated in this layer. ICMP may be used here for network monitoring . 1 This layer handles transmission errors and passes data to the physical hardware such as routers . It also sets out the final format of data packets . Q uesto's Q uestions 2.7 - Protocols: 1. Describe each of the following protocols . Also, state the protocol's full name and draw an icon or diagram for each: a. TCP b. IP c. UDP d. HTTP & HTTPS e. FTP f. ICMP g. SNMP h. SMTP i. POP [1 each ] 2. State which protocol would be used in the following scenarios: a. Transferring a music file to a friend over the internet. b. Sending an email to a friend in Japan. c. Checking for errors on a network. d. Having a video call with a colleague in London. e. Receiving an email from the bank. f. Watching a video on YouTube. g. Checking the statistics of usage on a network [1 each ] 3. Summarise each layer of the TCP/IP stack and identify the protocols used in each layer . [ 8 ] 2.6 - Software Troubleshooting Topic List 3.1 - Server Types

Expansion Cards What is an expansion card? An expansion card is a circuit board that can be inserted into a computer and attached to the motherboard . Two important expansion cards are the graphics card and the sound card . Expansion cards are attached to the PCI slots on the motherboard. PCI stands for Peripheral Component Interconnect. Graphics Card Fan Port (HDMI / VGA) Memory PCI Connector What is a Graphics Card? A graphics card processes video calculations so that it can display images and videos on a monitor . Graphics cards are used by professional video gamers and animators . Any job that focuses on graphics must have a powerful graphics card. A computer without a graphics card relies on the CPU to do the graphical processing instead . Sound Card PCI Connector Sound Chip Transistor Line In Microphone Line Out 1 Line Out 2 Line Out 3 Jacks: What is a Sound Card? Most computers don’t need a dedicated sound card, only musicians and producers who require high-quality sound . When you use a microphone , a sound card converts analogue waves (a voice) into digital data (binary). When you use headphones or speakers , a sound card converts digital data (binary) into analogue waves (sounds). What is the difference between an integrated and dedicated card? An integrated card is directly wired into the motherboard. They are cheaper and generate less power because they use the RAM of the computer. Integrated GPUs are used for laptops as they generate less heat and are used for general computing uses (e.g. web browsing or watching movies). A dedicated card is separate from the motherboard and has to be attached through a PCI slot. They are more expensive and generate more heat , often requiring a fan, because it contains its own processor and memory . Dedicated cards are used by professionals who need higher quality features like better sound or graphics. KS3 Home

2.6 - Software Troubleshooting Exam Board: OCR Specification: 2016 - Unit 1 A software error occurs when a program or process stops working as expected. Software errors usually occur when programs are badly written or if a user inputs unexpected data . Common Faults System Freeze The computer freezes and pressing keys or moving the mouse gives no response . Commonly caused by having too many applications running simultaneously or a virus using too much memory . Unexpected Reboot To try and fix errors, a computer might get stuck in an endless loop of booting and rebooting . Other systems may frequently restart without warning . Stop Error This occurs after a fatal system error when the operating system stops , usually because of a driver software issue . Commonly known as the 'blue screen of death ' on Windows-based systems. Update Error While designed to fix errors, updates can sometimes bring more problems if they interfere with the current software . Troubleshooting Tools for Software Errors Event Viewer (Logs) If a software error does occur, then the same characteristics as a hardware error should be logged , such as the time and date of the error , the user logged in , and the device's problem history . Memory Dump Copies and displays the contents of RAM at the time of a crash to help a technician discover what happened . Baselines Before After A comparison of what the system is like after a crash compared to a fixed point in time beforehand. The baseline can be used to see differences which may have caused the computer to fail . Anti-Virus Checks if malware is running on a device, using up resources and slowing the system down. It could then be quarantined and deleted by the anti-virus. Installable tools can also be downloaded to investigate the system and find the cause of the problem . They may help detect corrupted files , uncover deleted files , and resolve other general hardware or software issues . Q uesto's Q uestions 2.6 - Software Troubleshooting: 1. Describe each of the four common types of software error : a. System Freeze b. Stop Error c. Unexpected Reboot d. Update Error [2 each ] 2. Describe each type of troubleshooting tool and explain how it can be used to discover and fix software errors. a. Event Viewer b. Memory Dump c. Baselines d. Antivirus Software e. Installable Tools [ 2 each ] 2.5 Communication Methods Topic List 2.7 - Protocols

5.1 - Ethical Issues Exam Board: OCR Specification: 2016 - Unit 1 What are ethics? Ethics refers to what is right and wrong . The following issues are often linked to or backed up by legislation. Whistle Blowing Definition: When a member of staff reveals that the organisation they work for are engaging in unlawful practices . This could include breaking privacy laws , threatening staff or environmental damage . In the UK , whistleblowers are protected by the Public Interest Disclosures Act (1988) . Under this law, whistleblowers are protected from being fired or being victimised (e.g. ignored for promotion ) as a result of their whistleblowing. Large organisations should consider establishing a whistleblowing policy that would outline how employees can raise concerns , who they should speak to and the support available to concerned staff. A famous whistleblower is Edward Snowden , who revealed in 2013 that many governments, including the USA and the UK, were spying on their civilians with widespread undocumented surveillance. Should Martin reveal that his company is dumping old computers into a lake or just stay quiet? Graham feels that, because of his disability, he is being ignored for a promotion that he deserves. Discrimination Definition: When an employee is treated unfairly because of a personal or physical characteristic over which they have no control . The Equality Act (2010) ensures equal treatment for all people irrespective of: race sexuality gender disability marital status (and many more) Examples of discrimination include offensive talk, harassment, unequal pay and being ignored for promotion. Use of Information Definition: Laws such as GDPR (General Data Protection Regulation ) and specifically the Data Protection Act (2018) ensure that organisations must responsibly process personal data. Organisations have a legal obligation to keep their employee and customer personal data secure and out of reach from unauthorised viewers. Considerations should be made about how the information is ethically collected , stored and processed . DataDyne backs up customer information on cloud storage - what if this data is compromised ? As part of quality assurance, Selside Bank double check performance reviews before submission. Codes of Practice Definition: A set of rules which explains how people working in certain professions are required to behave . Organisations may have a code of practice for: Confidentiality (rules on what data can and cannot be shared with others), Quality assurance (ensuring high quality is maintained for all products/services), Behaviour (setting out how employees are expected to behave at work and in communication with each other and customers), Equality and discrimination (being understanding and providing fair access to all employees). Employees must agree to the codes of practice so they are clear on their expectations of what is and isn't acceptable at work. The organisation can then discipline employees that broke the codes of practice they formerly agreed to. Online Safety Definition: Often companies will provide an induction (training ) to new employees about the organisation’s code of practice for using the internet whilst at work . If an individual does not behave safely online or breaks the organisation's codes of practice (by gambling at work for example) then they may be punished (e.g. fined or fired). Employees can ensure that they are safe online by using secure passwords that are regularly updated and preventing web browsers from remembering login details . Miriam changes her password each month to minimise the chance of hackers accessing her account. The CEO of Honey Media apologies in public after biased information led to a lawsuit and loss of reputation. Bias Definition: This is technically correct, but slanted , information that presents a one-sided view . For example, end-of year financial data that focuses on profits and ignores significant losses. Poor quality information may lead to an organisation being misinformed and not sufficiently responding to their customers' needs - for example if a survey was only completed by a small number of people it could generate biased results. As a result of poor quality information, organisations may suffer from damage to their reputation due to negative feedback and reviews from customers, possibly posted online. A lack of trust can occur if customers feel neglected because of decisions made using biased information of a poor quality, therefore reputational damage may lead to loss of customers . Q uesto's Q uestions 5.1 - Ethical Issues: 1. Describe what whistleblowing is and give 3 examples . [4 ] 2. Describe what discrimination is and give 4 examples . [5 ] 3. Which law relates to the use of information ? [1 ] 4a. Describe 2 things that may be included in an organisation's codes of practice . [4 ] 4b. Explain why employees must agree to their company's codes of practice [4 ]. 5. Describe 2 things an employee should do to stay safe online . [2 ] 6a. What is biased information ? [2 ] 6b. Describe 3 possible effects to a company if they use biased information . [6 ] 4.6 & 4.7 - Bodies & Certification Topic List 5.2 - Operational Issues

3.2b: Protocols & Layers Exam Board: OCR Specification: J277 Protocols A protocol is a set of rules that allow devices on a network to communicate with each other . TCP / IP (Transmission Control Protocol / Internet Protocol) TCP / IP is actually two separate protocols that combine together. TCP is a protocol that allows packets to be sent and received between computer systems. It breaks the data into packets and reorders them back into the original data at the destination. IP is a protocol in charge of routing and addressing data packets . This ensures data packets are sent across networks to the correct destination . It is also an addressing system - every device on a network is given a unique IP address so data packets can be sent to the correct computer system. HTTP is used to transfer web pages over the Internet so that users can view them in a web browser . All URLs start with either HTTP or HTTPS (e.g. https://www.csnewbs.com). HTTPS is a more secure version of HTTP that works with another protocol called SSL ( Secure Sockets Layer ) to transfer encrypted data . You should see a padlock symbol in the URL bar if your connection to that website is secure. HTTP/HTTPS (Hypertext Transfer Protocol) Transfer Protocols FTP ( File Transfer Protocol ) is used to transfer files across a network. It is commonly used to upload or download files to/from a web server . SMTP ( Simple Mail Transfer Protocol ) is a protocol used to send emails to a mail server and between mail servers . POP ( Post Office Protocol ) and IMAP (Internet Message Access Protocol ) are both protocols for receiving and storing emails from a mail server. POP will delete an email from the email server once it has been downloaded to a device . Pop! IMAP syncs the message with an email server so it can be accessed by different devices . IP Address & MAC Address There are two versions of IP addressing currently used - IPv4 and IPv6 . IPv4 is a 32-bit address , represented in denary , that allows for over 4 billion unique addresses . It has four 8-bit segments of denary values (from 0 to 255) separated by full stops . IPv4 example: 145.13.218.102 IPv6 is a 128-bit address , represented in hexadecimal , that allows for an undecillion unique addresses . It has eight 16-bit segments of four hexadecimal values (0000 - FFFF), separated by colons . IPv6 example: 736E:1029:A4B3:902D:77B2:72FF:AE62:0912 A MAC address is a unique hexadecimal number assigned to each network interface card/controller inside a networked device such as a router or laptop . A MAC address is a 48-bit address made up of six 8-bit pairs in hexadecimal , separated by dashes . While an IP address may change , the MAC address can’t be changed . MAC stands for Media Access Control . Network Interface Card (NIC) MAC example: 19-C2-D1-47-AA-38 Networking Standards Networking standards are rules that allow computer systems to communicate across networks . Standards have been created to ensure devices can exchange data and work together by interpreting signals in the same way , regardless of the manufacturer . TCP/IP Stack & Layers What is TCP/IP? TCP/IP (Transmission Control Protocol / Internet Protocol ) is a set of protocols that operate on different layers . These two protocols are used together to allow computers to communicate on a network . What is a protocol layer? A layer is a division of network functionality - each layer provides a specific function to assist the transmission of the data that is being sent. TCP/IP is split into four layers (named Application , Transport , Internet and Link ). Important Note: You do not need to know any layer names or the purpose of any specific layers in the OCR GCSE J277 specification , just what layers are and why they’re used . Why are protocol layers used? Layers are self-contained , so they allow different developers to concentrate on one aspect of the network at a time . A layer can be taken out and edited without affecting other layers . Protocol layers are used to visualise the different parts of a network , as each of the four layers of TCP/IP has a specific role and is associated with different protocols . Protocols are broken down into well-defined , specific layers to simplify design , making it easier to identify errors (known as troubleshooting ). Each layer uses specific protocols , so layering ensures these protocols are applied in a specific order . This process uses abstraction and layers only communicate with adjacent layers for easy compatibility . Q uesto's Q uestions 3.2b - Protocols & Layers: 1. Describe each of the following protocols . It might be helpful to also draw an icon or small diagram for each one: a. TCP [ 2 ] b. IP [ 2 ] c. HTTP & HTTPS [ 3 ] d. FTP [ 2 ] e. SMTP [ 2 ] f. POP3 & IMAP [ 2 ] 2. State which protocol would be used in the following scenarios : a. Transferring a music file to a friend over the internet. [ 1 ] b. Sending an email to a family member in America. [ 1 ] c. Using a webpage to enter a password securely. [ 1 ] d. Receiving an email from a bank. [ 1 ] 3a. What are networking standards ? [ 2 ] 3b. What is TCP/IP ? [ 2 ] 3c. What is a protocol layer ? [ 2 ] 3d. Give at least two reasons why protocols are split into layers . [ 4 ] 3.2a - Wired & Wireless Networks Theory Topics 4.1 - Security Threats

2.5 & 4.2: Communication Methods Exam Board: OCR Specification: 2016 - Unit 1 Sections 2.5 and 4.2 are very similar so both are mixed within this page. There are many ways that employees of a business can communicate between staff members or with their customers . Text-based Communication Letter ✓ It is a traditional method of communication that can be used for formal occasions such as job offers or resignations . ✓ It can be kept and stored for physical evidence - e.g. keeping an applicant's CV in case an opportunity arises in the future. X Requires postage costs to be sent in the mail (a first-class stamp is now £1.65 ). Overseas delivery is even more expensive . X Takes several days time to be received in the post and may be lost . X A letter can't include certain formats like video. Text Message (SMS) ✓ Can reach a large audience at once with one batch message . ✓ Good for short messages - e.g. appointment reminders or confirmation codes for two-factor authentication . ✓ Doesn't require an internet connection to receive messages. X Limited to short messages (160 characters ) with no multimedia . X Text messages can cost to send each message. SMS stands for Short Message Service . Email ✓ Easily send information to many people at once, instantly . ✓ Can include documents , multimedia attachments and links . ✓ Can send targeted emails to customers on a mailing list with new products or sales promotions . X Important messages may be lost in the spam folder. X Phishing scams can spread malware via email attachments. Instant Messaging ✓ Works in real-time - messages are sent and received instantly . ✓ Attachments and hyperlinks can be sent. ✓ Can be used by support staff to help customers in real-time. X Quick speed means it's less suitable for formal conversations like interviews. X Internet access issues will disrupt any conversations . Voice-based Communication Cellular ✓ Can hear how something is said , unlike text responses. ✓ Fastest method of communication - also allows reactive conversations that can quickly change based on previous responses. X Impacted by cellular reception - won't work in remote areas / underground. X Can't see the other person's body language, presentation or facial expressions. Teleconferences ✓ Allows for groups of people to communicate at once . ✓ Businesses can use teleconferencing to communicate between offices / individuals across the world . X The quality of the call may be affected by a group's poor reception . X Because a group is communicating, people may speak over each other , especially if there is a time delay . VoIP (Voice over Internet Protocol) ✓ Allows a user to make calls over the internet (e.g. using WhatsApp). ✓ Cheaper (can also be free) to make calls rather than using a cellular network . X Relies on a good-quality internet connection . X Can potentially be less secure than cellular connections. hi there Personal Assistants ✓ Speeds up processes by making appointments, checking information or connecting to smart devices. ✓ Voice-activated - can be used whilst otherwise busy , such as typing, cooking or driving. ✓ The language can be changed to suit people's preferences. X Huge privacy concerns as companies store audio data for voice recognition and track all commands made to the device. X There may be recognition issues as sometimes the assistant doesn't understand a command . Online Communication Video Conferences ✓ Users can connect to the call (e.g. using Zoom, Skype, or Google Meet) remotely , saving time and money instead of all travelling to one location. ✓ Can be used for interviews as it allows the applicant and the interviewers to see each other and look for body language . ✓ Users can share information visually , such as designs. X A high-bandwidth connection is required to send and receive video data reliably . X A poor internet connection (e.g. a weak WiFi signal ) will result in low-quality video that may stutter or drop out , making it hard to communicate clearly . Social Media ✓ Businesses can quickly share information with a large online audience , including new potential customers . ✓ Posts can be in d i fferent formats such as text, images, videos or links to other websites. ✓ Direct messages sent on social media may be seen and responded to faster than alternatives like using email if push notifications are enabled on a phone. ✓ Some social media sites like Facebook allow for private , invite-only groups to communicate with like-minded users in a secure way. X Businesses must be cautious about what they post so as not to accidentally offend others and damage their reputation . X Social media posts and customer comments must be carefully managed , so a social media manager should be hired. Blog / Vlog ✓ Share information with followers in text , images and video formats . ✓ Blogs and vlogs can unite people with similar interests , such as a cookery blog or travel vlog. ✓ Companies can use a blog to promote new products and provide details of upcoming events to try and attract new customers . X Takes a lot of effort and time to create posts, especially editing videos for vlogs. X Bad behaviour or language in vlogs can bring punishment. Several YouTubers have lost their reputations following videos they have posted. Q uesto's Q uestions 2.5 & 4.2 - Communication Methods: 1. Describe three advantages and three disadvantages for each type of communication method . You will need to think of or research some more than the examples listed on this page. a. Letter b. SMS (Text Message) c. Email d. Instant Message e. Cellular Call f. Teleconference g. VoIP Call h. Personal Assistant i. Video Conference j. Social Media k. Blog / Vlog [6 each ] 2. Explain what VoIP stands for and what it allows a user to do. [ 2 ] 3. Describe which communication method would be most appropriate for the following scenarios and why : a. Informing your boss you are going to resign. b. Communicating with management about raising your pay. c. Chatting to team members about when the Christmas party is. d. Sending promotions to thousands of customers. e. Interviewing a potential new employee who is in a different country. f. Talking with a group of investors about the company's latest data. [2 each ] 2.6 - Software Troubleshooting 2.4 Operating Systems 4.1 Communication Skills 4.3 - Personal Attributes Topic List

3.4 - Connection Methods Exam Board: OCR Specification: 2016 - Unit 1 Local Area Network (LAN) A Local Area Network (LAN ) is a network in which the computer systems are all located geographically close to each other , for example, in the same building or on the same site , like a school or office . A type of LAN is a Wired Ethernet LAN ( technically Ethernet is a protocol that controls how data is transmitted over a LAN). Wired Ethernet LANs have a high bandwidth so data can be transferred quickly and because it uses cables the data is harder to intercept than a wireless network. Metropolitan Area Network (MAN) A Metropolitan Area Network (MAN ) connects several LANs together to cover the range of a town or city , for example a university campus network. MANs are usually very efficient at providing fast communication for cities , with high connection speeds through the use of fibre optic cables. Wide Area Network (WAN) A Wide Area Network (WAN ) is a network spanning a large geographical area , such as multiple cities or countries . The internet is the ultimate example of a WAN as it stretches across the entire world. Different types of WAN rules and standards are used: ADSL ADSL ( Asymmetric Digital Subscriber Line ) is a method of transferring data across copper wire telephone lines . ADSL is contended, which means that connection speeds are affected and slowed down by more systems that use the network at the same time . The old copper wires also affect data transfer over long distances and can cause data packet loss . Security is also an issue, as the line is shared with others, making data interception more likely . To improve security, a firewall and/or VPN (Virtual Private Network) may be used. Because ADSL uses the telephone system, a modem is require d at both the sending and receiving ends of the connection. A microfilter is also required to allow internet and telephone access at the same time . ADSL is contended - shared between sites. Internet Service Provider ADSL requires a modem Leased Line Leased Line is a method of providing an uncontended , fixed-bandwidth data connection . The user maintains a dedicated connection that is more secure and, because it is uncontended , will have the same speed all of the time , regardless of how busy the network is . Bandwidth is high , security is better , the connection speed is constant and the network is full-duplex (allowing for data transmission both ways simultaneously). These advantages come at a high cost - possibly hundreds of pounds per month - as well as an expensive installation that can take time to be put in place . As it is a complex configuration , a CSU/DSU (Channel Service Unit/Data Service Unit) device is required to properly terminate the leased line . Internet Service Provider Leased Line is dedicated. C A CSU/DSU is required for a leased line. ISDN ISDN (Integrated Services Digital Network ) transmits video and voice data simultaneously over traditional copper telephone wires . This method uses a circuit-switched network where all data packets take the same route between computer systems. Voice Networks Voice networks primarily transfer audio data using phones and telephone lines . PSTN PSTN (Public Switched Telephone Network ) is the global collection of wired public telephone networks that are used to transmit data over a long distance. PSTN is fixed into position using underground cables and therefore the connection quality is much more consistent than other voice networks. Using a wired connection like a PSTN is more reliable and communication will be clearer than alternatives such as cellular or satellite methods. Cellular Cellular networks require a cell tower (also called a transmitting tower ) to be in close proximity to the communication device. Cellular networks have a greater range than PSTN, but buildings and poor weather can disrupt this point-to-point communication method (where line of sight is necessary ). Each cell tower is also connected to the PSTN . Satellite Satellite networks use point-to-multipoint communication by using satellites above the Earth's atmosphere that receive a transmission and rebroadcast them back to Earth. Because of the distance between the communication device and the satellite (potentially thousands of miles ), there is a delay between data transmission and it being received . Satellite networks are beneficial in remote locations , such as natural disaster zones , where the cell tower may not be present or may be damaged. Transmitting large files using satellites may take longer , and it is not recommended for low-latency needs such as video gaming. There are different types of satellites used in communication and networking : Geostationary satellites are used for consistent communication over a specific region , such as TV broadcasts and weather monitoring . They can also be used to transfer data between remote locations . Low-Earth orbiting satellites are closer to the ground so they enable fast communication for internet services . Medium-Earth orbiting satellites are often used for GPS (Global Positioning System ) and other navigation systems . A global positioning satellite is an example of this type of satellite that provides time and geolocation data to GPS receivers back on Earth. Diagrammatical Representation In an exam, you may be asked to draw a diagram representing how networks are connected . This is different from drawing a network topology (e.g. ring or mesh) and refers to: Connection type (e.g. ADSL / Leased Line). Devices (e.g. router / modem), Security methods (e.g. firewall / VPN) Two LANs connected using a Leased line Two LANs connected using an ADSL line Rules for drawing a network diagram: Label each device and label your LANs . Use appropriate symbols and be neat . There are no set symbols, just be consistent (e.g. both modems are the same shape). ADSL must have a modem and VPN router + Firewall . (ADSL is not very secure so it needs to be protected with the VPN router and firewall. It also uses the telephone line across the internet so it requires a modem at both ends). Leased Line must have a router , a direct connection and CSU/DSU . (Leased line is a secure and direct connection - so it doesn’t need a firewall or VPN router and should be direct (not across the internet )). Q uesto's Q uestions 3.4 - Connection Methods: 1a. What is the definition of a LAN ? [ 2 ] 1b. Describe two benefits of using a wired Ethernet LAN . [ 4 ] 2. What is the definition of a MAN ? [ 2 ] 3a. What is the definition of a WAN ? [ 2 ] 3b. What is the difference between a contended and an uncontended network? [ 2 ] 3 c. Describe the differences between a leased line and ADSL . You should discuss security , connection speed and contention ( contended or uncontended ) . [6 ] 3d. Describe the use of any two network devices required for either a leased line and/or for ADSL . [ 4 ] 3e. Describe the purpose of ISDN . [ 2 ] 4a. Compare the use of PSTN and Cellular methods to make telephone calls . [ 4 ] 4b. Explain 1 way that a satellite network should be used and 1 way it shouldn't be used . [ 4 ] 5. Draw a diagram to show how a leased line or ADSL network can be set up between two existing LANs. [6 ] 3.3 - Network Characteristics Topic List 3.5 - Business Systems

5.6 - Data & System Disposal Exam Board: OCR Specification: 2016 - Unit 1 Computer components such as circuit boards, processors and monitors contain hazardous materials that cannot be disposed of in traditional ways such as rubbish collection and landfills. For security reasons, data must also be disposed of carefully so that it is not returned to a readable format by unauthorised viewers . Legislation In recent years, the government has introduced different laws that relate to the safe disposal of computer equipment to help reduce environmental impact . Waste Electronic and Electrical Equipment ( WEEE ) Directive : This provides guidance on how hazardous materials should be disposed of safely . This includes materials such as mercury (found in smartphones and newer monitors ) and toner cartridges in printers . These materials can damage the environment if not disposed of appropriately . Waste Acceptance Criteria ( WAC ): Equipment must meet these rules before it can be sent to a landfill . Hazardous materials, such as the elements in computer monitors , do not meet these criteria and should not be accepted . Hazardous Waste Directive : This ensures businesses safely store hazardous materials and use authorised businesses to dispose of the waste . Hazardous materials include mercury and hexavalent chromium . Data Protection Act ( DPA ): One principle of the DPA specifies that data should only be kept for a reasonable amount of time until it is securely deleted . Data stored on customers should be checked regularly and permanently deleted if no longer required . Methods of Data & System Disposal Overwriting is when new data is written to the hard disk drive to replace the current data - essentially resetting the data . Remember all data stored by a computer is in a binary format . Overwriting just once is usually not enough to remove all evidence of the data and the process may be repeated several times . Overwriting data causes no damage and means the drive can still be used for other purposes afterwards. Electromagnetic wiping uses a machine called a degausser , which has a very strong electromagnetic coil , to completely wipe the hard disk drive . Many large organisations use degaussers to be sure that their data is no longer on the devices they have used so it can’t be restored and accessed by unauthorised viewers . Degaussers are expensive to buy but it allows the device to be used again for other purposes afterwards as it is not physically damaged. A third option is the physical destruction of a computer system or storage device , like a hard disk drive , which guarantees the data is permanently inaccessible . However, physical destruction also renders the storage media unusable again for other purposes. Examples of physical destruction include shredding (e.g. a CD shredder ) or tools such as sledgehammers if no other option is available. Q uesto's Q uestions 5.6 - Data & System Disposal: 1. Describe the purpose of 4 different pieces of legislation relating to how data or computer systems should be disposed of safely . [8 ] 2a. State 3 methods of data and system disposal . [3 ] 2b. Describe 1 advantage and 1 disadvantage of using each method you stated in 2a. [6 ] 5.5 - Digital Security Topic List

5.2 - Operational Issues Exam Board: OCR Specification: 2016 - Unit 1 What are operational issues? Operational issues refer to potential problems that could disrupt the workflow and efficiency of an organisation . They relate to processes within an organisation and the way that the company operates on a daily basis . Security of Information Definition: Organisations must ensure that data is stored securely to minimise the chances of data loss , corruption or unauthorised manipulation . Having information stolen through a hacking attempt, for example, would negatively impact the company and its customers and possibly lead to consequences such as poor publicity , a loss of business and reputation , fines and bankruptcy . One principle of the Data Protection Act is that data must be stored securely . Organisations can use security methods such as firewalls , antiviruses or physical protection such as biometrics to keep personal information secure . Health & Safety Definition: Ensuring that employees, clients and visitors are physically protected on-site . The organisation should create a health and safety policy that staff need to read and possibly sign at the start of their work placement. The policy should include information about how to avoid injury when using the systems, how to safely maintain the equipment and whom to contact for help . Disaster & Recovery Planning Important data is often stored on a computer network, so a detailed and effective disaster recovery policy must be in place in case an unexpected disaster occurs. Disasters include natural disasters (e.g. fire, flood, lightning), hardware failure (e.g. power supply unit failing), software failure (e.g. virus damage) and malicious damage (e.g. hacking). There are three clear parts to a disaster recovery policy: Before the disaster: All of the possible risks should be analysed to spot if there are any weaknesses in preparation. Preventative measures should be taken after the analysis, such as making rooms flood-proof or storing important data at a different location . Staff training should take place to inform employees what should happen in the event of a disaster. During the disaster: The staff response is very important – employees should follow their training and ensure that data is protected and appropriate measures are put in place. Contingency plans should be implemented while the disaster is taking place, such as uploading recent data to cloud storage or securing backups in a safe room and using alternative equipment until the disaster is over. After the disaster: Recovery measures should be followed, such as using backups to repopulate computer systems. Replacement hardware needs to be purchased for equipment that is corrupted or destroyed. Software needs to be reinstalled on the new hardware. Disaster recovery policies should also be updated and improved . Organisational Policies Definition: Creating policies that outline acceptable computer and network use . Workplaces and schools often require people to sign an acceptable use policy ( AUP ) before being allowed to use the network . An AUP may include the philosophy of the organisation , rules for the personal use of IT resources and the consequences of breaching the policy . An AUP is similar to codes of practice from 5.1 . Change Management Definition: Change management is a formal approach by an organisation to lead a change in the way a business or project is run . This may include editing budgets , redefining expected deadlines , reconsidering how resources are used or changing staff roles . Advantages of change management: Reduces the likelihood of things going wrong during development. Creates a clear log of changes and improvements that are to be made. Allows changes to be approved and discussed before they happen. Formalises the process and sets out clear rules for changes . Disadvantages of change management: Can make the process of change more complicated . It can reduce the responsiveness of developers if everything must go through a formal process. It can be challenging to implement successfully. To work effectively, it needs everyone to follow the process . Scales of Change There are two main reasons why major change will occur in an organisation. Change Drivers Definition: Companies must change to stay up to date with the times and new technology . Change drivers are factors that force a business to change , such as: New legislation New competitors in the market New platforms (e.g. mobile technology and game consoles) to sell products on Economic changes Changes in business practice Social changes Change Needs Definition: Companies must change if the needs and focus of the organisation are altered over time . This reflects the changing needs of the business , often due to advancements in technology , such as: New equipment (e.g. replacing a slow network with a faster fibre optics network) Customer interaction (e.g.communicating with customers in new ways, such as social media apps) Workplace shifts (e.g. providing remote access for employees to access work and services at home) Q uesto's Q uestions 5.2 - Operational Issues: 1. Describe 3 possible consequences to an organisation if data is not stored securely . [6 ] 2. Describe the purpose of a health and safety policy and state 3 things that may be included in one. [4 ] 3a. Describe, giving specific examples , different types of possible disaster . [5 ] 3b. Describe the steps an organisation should take before , during and after a disaster occurs . [10 ] 4. Describe 3 things that may be included within an Acceptable Use Policy (AUP ). [3 ] 5a. What is change management ? Give 2 examples of when change management may be used. [4 ] 5b. Describe the advantages and disadvantages of a company deciding to implement change management . [8 ] 6a. Describe the difference between change drivers and change needs . [2 ] 6b. Describe 3 examples of change drivers and 3 examples of change needs . [6 ] 5.1 - Ethical Issues Topic List 5.3 - Threats