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4. Hyperlinks HTML Guide Watch on YouTube: A hyperlink is a link to another web page . In this section, you will link your page to a real website, like Wikipedia. Hyperlinks require the anchor tags and Copy a URL Firstly you need to copy the full web address of the web page that you would like to link your page to. Choose an appropriate web page that relates to your chosen topic. Create the Anchor Tag 4. Close the start of the tag . 1. Open the start of the tag . 2. Type href (stands for hypertext reference ). 3. Paste the URL inside speech marks . 5. Type the text you want the user to click on . 6. Time to close the tag . When you save your webpage and run it in a browser you will be able to click highlighted text to open the website you have chosen. Add at least three different hyperlinks to your webpage. Try to add the 2nd & 3rd links without looking at this page - practise makes perfect. Add a Hyperlink within a Sentence You can also create an anchor tag within a sentence. Hyperlinks are important to link webpages together. Next is time for adding pictures! Either change one of your previous hyperlinks to be in the middle of a sentence or create a new one. 3. Text Tags HTML Guide 5. Images

3.2a: Wired & Wireless Networks Exam Board: OCR Specification: J277 Wired Connections Wireless Connections Wireless connections, such as WiFi or Bluetooth , use no cables but require a wireless network interface card (WNIC ). Wireless connections generally have a slower speed and can be affected by the computer's distance from the wireless router as well as obstacles like walls or bad weather. Wired connections use physical cables , such as copper or fibre optic wires , and require a network interface card (NIC ) to connect to a network. These wired connections use a wired connection protocol - most commonly Ethernet . Restricted Movement Faster More Secure NIC Required Freedom of Movement Slower Less Secure WNIC Required Q uesto's Q uestions 3.2a - Wired & Wireless Networks: 1. Briefly compare wired and wireless networks in terms of movement , transmission speed , security and required hardware . You could answer this in the form of a table. [ 8 ] 3.1b - Network Hardware & Internet Theory Topics 3.2b - Protocols & Layers

1.4 - Internet Connections Exam Board: OCR Specification: 2016 - Unit 2 The internet i s a global network of interconnected networks . There are multiple methods of connecting to the internet . Wired Connections Copper Cables Copper cables are a cheaper type of wired internet connection that may be poorly insulated and therefore susceptible to electromagnetic interference . Copper cables are more likely to suffer from attenuation (network distortion ). However, they are malleable (easier to bend) and less likely to break than other cables such as fibre optic. They have a lower bandwidth - cannot transmit as much data at once - than fibre optic cables. Fibre Optic Cables Fibre optic cables are a very fast but expensive type of wired internet connection. Signals are transmitted as waves of light through a glass tube. Because of this fibre optic cables are not affected by electromagnetic interference and suffer less from attenuation . Fibre optic cables have a higher bandwidth - can transfer more data at one time - than copper cables but they are more fragile . Wireless Connections Bluetooth Bluetooth is a temporary short-range communication between devices within a limit of about 10 metres . For example, Bluetooth can be used to transfer audio files from one smartphone to another. The close proximity is a disadvantage but no other hardware is required for a connection. Microwave Microwave connections use radio waves to send signals across a large area via microwave towers . It can transmit a large amount of data but antennas must be in the line of sight of each other with no obstructions . Microwave connections are affected by bad weather , leading to higher chances of attenuation (network distortion ). 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 (roughly 45,000 miles), there is a delay between data transmission and it being received. GSM / 5G GSM (Global System for Mobile communications ) is a technology for allowing mobile phones to connect to a network for calls and text messages. Advances in mobile technology are classified by generations such as 4G and 5G (the current generation). Each generation is generally faster, more secure and allows for new opportunities. Connection Characteristics When connecting to the internet there are several characteristics that a user must consider: Strength Range Latency Bandwidth Storage Capacity Contention Latency is the delay when sending data across a network. Bandwidth is the maximum amount of data that can be sent across a network at once . Contention refers to whether a network is dedicated ( uncontended ) or shared between users ( contended ). Q uesto's Q uestions 1.4 - The Internet: 1. Compare the differences between copper and fibre optic cables (possibly in a table) by the following features: a. Price b. Bandwidth c. Interference d. Attenuation e. Malleability / Fragility [2 each ] 2. Describe each of the different types of wireless connection . Try to list 1 advantage and 1 disadvantage of using each type. a. Bluetooth b. Microwave c. Satellite d. GSM / 5G [5 each ] 3a. State the 6 characteristics of a network. [6 ] 3b. Describe what is meant by the following characteristics : i. Latency ii. Bandwidth iii. Contention [1 each ] 1.3 - Access & Storage Devices Topic List 1.5 - WWW Technologies

4.6: Graphical Representation Exam Board: Eduqas / WJEC Specification: 2020 + There are two main types of graphics used in computer systems: raster (also known as bitmap ) and vector graphics. Raster (Bitmap) Graphics Vector Graphics Raster graphics are made up of a grid of pixels . Vector graphics use objects (lines and curves ) to mathematically form shapes. If scaled to a larger size, a vector graphic does not lose any image quality . If scaled to a larger size, a raster graphic loses image quality . Raster graphics are generally larger in file size because data is stored for each pixel . Vector graphics are generally smaller in file size . Examples of raster images include photographs and screenshots. Examples of vector graphics include logos and cartoons. How to Calculate File Size File Size = Resolution x Colour Depth The resolution of an image is the width in pixels multiplied by the height in pixels. x The colour depth (also known as bit depth ) is the number of bits that are used to represent each pixel's colour . 1 bit represents 2 colours (0 or 1 / black or white). 2 bits will allow for 4 colours, 3 bits for 8 colours, 4 for 16 etc. A colour depth of 1 byte (8 bits ) allows for 256 different colours . Remember you must multiply the colour depth , not the number of available colours (e.g. 8 not 256). The RGB (Red , Green , Blue ) colour model uses 3 bytes (a byte of 256 red shades , a byte of 256 green shades and a byte of 256 blue shades ) that together can represent 16.7 million different colours. Example Height = 6 bits Resolution = height x width Resolution = 8 x 6 = 48 bits -------------------------- Colour Depth = 1 bit (only 2 colours) -------------------------- File Size = Resolution x Colour Depth File Size = 48 x 1 = 48 bits File Size in bytes = 48 ÷ 8 = 6 bytes File Size in kilobytes = 6 ÷ 1000 = 0.00 6 kilobytes Width = 8 bits Look carefully at the exam question to see if the examiner is expecting the answer in bits, bytes or kilobytes . Always calculate the file size in bits first then: Divide the file size in bits by 8 to convert to bytes . Divide the file size in bytes by 1000 to convert to kilobytes . Metadata for Graphics Metadata is additional data about a file . Common image metadata includes: Dimensions Colour depth Make Model Orientation Exposure time Metadata is important, For example, the dimensions must be known so the image can be displayed correctly . Metadata for a smartphone-taken picture: width in pixels, e.g. 720 height in pixels, e.g. 480 Q uesto's Q uestions 4.6 - Graphical Representation: 1. Describe three differences between raster (bitmap) and vector images . [ 6 ] 2. How many colours can be represented with a colour depth of... a. 1 bit [ 1 ] b . 5 bits [ 1 ] c. 1 byte [ 1 ] 3. How is the file size of an image calculated? [2 ] 4a. An image file has a width of 10 pixels , a height of 8 pixels and a colour depth of 2 . What is the file size in bytes ? [3 ] 4b. An image file has a width of 120 pixels , a height of 120 pixels and a colour depth of 1 . What is the file size in kilobytes ? [3 ] 4c. An image file has a width of 32 pixels , a height of 21 pixels and a colour depth of 1 . What is the file size in bytes ? [3 ] 5. State what is meant by metadata and give three examples of metadata for a graphics file. [ 3 ] 4.5 Character Sets & Data Types Theory Topics 4.7 - Sound Representation

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 relatively close to each other , for example, in the same building or on the same site, like a school . 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 ) covers 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. There are different types of WAN rules and standards that are used: ADSL ADSL ( Asymmetric Digital Subscriber Line ) is a method of transferring data across copper wire telephone lines . Because ADSL uses the telephone system it requires a modem at both the sending and receiving end of the connection. A microfilter is also required to allow internet and telephone access at the same time. While bandwidth is high with this method, is not as secure as other methods such as leased lines so a firewall and/or VPN (Virtual Private Network) would be needed to improve security. ADSL is contended which means that connection speeds are affected and slowed down with more systems that use the network 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 price tag - possibly hundreds of pounds per month. 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 or transmitting tower to be in close proximity to the communication device. Cellular networks have a greater range than PSTN but this point-to-point communication method (where line of sight is necessary) can be disrupted by buildings and poor weather. 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 (roughly 45,000 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. Diagrammatical Representation In an exam you may be asked to draw a diagram that represents how networks are connected to each other. 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

1.6 - Information Formats Exam Board: OCR Specification: 2016 - Unit 2 The following formats are used to display information on the internet . Web Pages Web pages can be used for a diverse range of purposes including advertising products, reporting information , displaying images and eCommerce (online shopping). There are two types of web page: Static web page Static web pages contain content that is pre-built and remains the same each time the page is loaded . Static web pages are cheaper and easier to create and load quicker ; they use basic HTML. It can be changed by the site editor but will appear the same for everyone who has access to it, such as a classic promotional website for a small company. Dynamic web page Dynamic web pages are generated when they are loaded and can appear different to different users . Dynamic web pages are harder to code but they can be linked to databases to allow them to show personalised content to whoever is viewing the site; they are written in server-side languages like PHP. The Amazon homepage is an example of a dynamic web page as personalised deals based on previous user history will be shown if you are logged in with an account. Blogs Blogs are used to share information with like-minded individuals, such as those who enjoy the same hobbies or beliefs . Charities , game developers and other businesses also use blogs as a way of updating their customer base with what they have done or what they are working on. Blogs can feature multimedia such as text, images, videos and links to other sites. Advantages of Blogs Disadvantages of Blogs ✓ Share information with followers in the format of text, images and video . ✓ Blogs and vlogs can unite people with similar interests , such as a cookery blog or travel vlog. X Takes a lot of effort and time to create posts, especially if videos need to be edited before posting. Potential customers could be lost if blogs aren't updated regularly . X It can be difficult to build up a customer base directly from a blog. Posts must be engaging , researched and correct . Podcasts A podcast is a downloadable audio file , usually on a certain topic such as sports or gaming that can be listened to when convenient for the user. Spotify and Apple Music have a wide library of podcasts. Advantages of Podcasts Disadvantages of Podcasts ✓ Podcasts are not (usually) recorded live , so they can be edited and uploaded at a certain time each week. ✓ Podcasts can be listened to when convenient for the user, so they can't 'miss' it and can catch up when is best for them. ✓ Podcasts are becoming more and more popular , so the possible audience base is growing each year. Celebrity guests are one way to entice more listeners. X Takes time to record a podcast, especially if they need to be edited to add in music or sound effects or to remove mistakes . X It can be difficult to build up an audience directly from a podcast. Podcasts should be on a topic that interests people and spoken in an engaging way. Streamed Audio & Video Streaming is the process of receiving video / audio data in a continuous flow . This allows the user to access the video / audio immediately , without having to wait for the file to download entirely. For example, the BBC provide live radio streaming online for their radio shows and BBC iPlayer allows users to watch 'catch up' programs that previously aired. YouTube is a widely-used streamed video platform and Spotify is a popular streamed audio service. Advantages of Streamed Media Disadvantages of Streamed Media ✓ Streaming does not require data to be downloaded entirely before use - users can watch / listen as soon as the connection starts . ✓ Streaming is harder for users to share than downloading a file . Netflix uses this as a form of piracy protection . X Streaming requires high bandwidth so users may suffer performance issues on slower devices and networks . X Streaming requires a constant network connection compared to downloadable media which can be used when offline / outside. Social Media Channels Social media channels provide a huge amount of data on users in an informal space. Organisations can receive feedback through user posts and comments . Real-time statistics like views, likes and shares provide an insight to user opinion . Social media channels include traditional sites such as Facebook and Twitter as well as business and recruitment platforms such as LinkedIn . Discussion boards and forums , such as Reddit , are increasingly popular for users to discuss similar hobbies and interests such as politics, gaming and healthy eating. Advantages of Social Media Disadvantages of Social Media ✓ Social media can increase a business' online presence as it is online 24/7 for users to comment and interact with posts. ✓ Posts can be shared between users and their contacts, allowing a post to 'go viral' and be seen by potentially millions of viewers . ✓ Posts can be shared in different information styles such as text , images , video or hyperlinks to other websites. ✓ Businesses can use social media to communicate with their customer s , such as direct messages on Facebook if a customer is unhappy. X Businesses may need to hire a social media manager to interact with customers , update posts and remove spam. X Negative posts can be shared and spread very quickly , such as if a customer complains about how a business treated them poorly. X Businesses must be cautious about what they post , to not accidentally offend others and damage their reputation . Emails Emails can be used to provide information to a large amount of people almost instantly . A company may use an email to advertise new products , inform potential customers of a marketing promotion or target specific users based on previous interactions. Advantages of Emails Disadvantages of Emails ✓ Faster (almost instant) and cheaper (usually free) to send an email compared to traditional letters . ✓ Files can be attached to the email, such as images, videos or forms to complete. ✓ An audit trail can be kept, recording communication between the company and its customers. ✓ Emails can be sent, delivered and read at the user's convenience and to any internet-enabled device across the world . X An internet connection is required to open and read the email. Larger attachments may not open on mobile devices. X Malware can spread through email attachments. Phishers use emails to gain access to personal information and account details . X Some attachments sent via email may be unreadable on different devices / operating systems. X Emails may automatically go into the spam / junk folder and be deleted without being read . Document Stores Document stores allow users to store online files in cloud storage . Common services are Google Drive , Dropbox and Microsoft's OneDrive . Storing documents in the cloud allows users to edit and access them from any location with an internet connection and opens up opportunities for collaboration . Many organisations offer cloud storage space for free up to a certain amount before charging customers for more data. Document stores are very convenient for users and replace the need for portable storage devices like USB sticks. Teachers can use documents stores to share resources with other staff in a school . Documents stores can only be accessed with an internet connection so files will be unavailable during maintenance or network failure. Users rely on the cloud hosting provider, such as Microsoft and Google to keep the data secure and available . RSS Feeds RSS Feeds (short for Rich Site Summary ) allow users to subscribe to updates from their favourite websites. It is a web feed that updates whenever a subscribed site releases new information. For example, the BBC used to post updates for important news headlines which appeared in a subscribed user's RSS feed. As of 2020 most browsers no longer have built-in RSS functionality and it is rarely used . Q uesto's Q uestions 1.6 - Information Formats: 1. Describe the difference between static and dynamic web pages . [4 ] 2. For each type of information format describe its advantages and disadvantages . a. Blogs [8 ] b. Podcasts [8 ] c. Streamed Audio / Video [8 ] d. Social Media [8 ] e. Emails [8 ] 3. Explain how document stores could be used by organisations and individuals . [4 ] 4. Explain what an RSS feed is and how an organisation could use it . [3 ] 1.5 - WWW Technologies Topic List 1.7 & 1.8 - Internet Pros & Cons

6.5 - Physical Protection Exam Board: OCR Specification: 2016 - Unit 2 RFID & Tokens Radio-frequency identification (RFID) uses electromagnetic fields to attach tags to physical objects . RFID tags can be embedded within 'dumb' objects such as clothing, packages and even animals. RFID is used with security tokens (such as an ID keycard ) to permit the access of authorised people to certain areas. RFID can be used by IT companies to track equipment and manage access . Shredding This is the cutting up of documents (paper or CDs ) into small pieces so that they cannot be reassembled and read. Sensitive data on paper or optical disc should be shredded when no longer required. Locks A lock can be used to prevent access to server rooms or sensitive data stores . Only authorised personnel with the right key will have access. Physical Security Measures Backup Backups should be taken regularly and stored at a secure location away from the main site. Backups could also be stored on cloud servers so that any damage to the organisation's building will not affect the backup as well. Biometrics Biometric devices require the input of a human characteristic (such a fingerprint , iris or voice scan ). The biometric data is checked against previously inputted data in a database . A match will allow access to the user. Security Staff Staff may be employed to physically prevent unauthorised people from accessing certain areas of a building where sensitive information is stored. They may check ID keycards or use surveillance like CCTV to monitor who is entering and exiting a secure area. Q uesto's Q uestions 6.5 - Physical Protection: 1. Explain how locks can be used as a physical security method within an organisation. [2 ] 2. Explain what RFID is and how it can be used with tokens as a physical security method. [3 ] 3. Explain how biometric devices can be used as a physical security method. [3 ] 4. Explain how security staff can be employed to protect data. [2 ] 5. What is the purpose of shredding ? [2 ] 6. Why should backups be stored off-site ? [1 ] 6.4 - Protection Measures Topic List 6.6 - Logical Protection

1.3 - Embedded Software: 1. What is an embedded system ? [3 ] 2a. Give two examples of an embedded system. [ 2 ] 2b. Research and describe another two examples of an embedded system. [ 4 ] 1.3: Embedded Systems Exam Board: OCR Specification: J277 Example: A washing machine has a control chip that manages the different program cycles. An embedded system is a computer system built into a larger machine to provide a means of control . Embedded systems perform a specific pre-programmed task which is stored in ROM . An embedded system uses a combination of hardware and software . They perform only specific tasks and often have a small amount of storage and low processing power . Example: A traffic light has a control chip that determines when to change to a green or red light. Q uesto's Q uestions 1.2 - CPU Performance 2.1 - Primary Storage Theory Topics

Exam Board: OCR 4.1d - Binary Calculations 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 4.1d - Binary Calculations: 1. What is cache memory ? [ 2 ] 4.1c - Signed Binary & Floating Point Theory Topics 4.1e - Shifts & Masks

2.4 - Information Management Exam Board: OCR Specification: 2016 - Unit 2 Management Information System (MIS) An MIS is used to collect, store, analyse and present data for an organisation. The system processes a large amount of data and organises it (such as in databases) so that it can be used for decision making and general data analysis . An efficient MIS can be used to display the financial status of an organisation, highlight areas of improvement and generate sales forecasts based on current data. Specifically, a bank could use an MIS for: Looking at the number of customers that visit each branch. Forecasting takings based on historical data. Profiling customers. Identifying customers who haven’t saved recently to target them for email. Benefits of an MIS: Integrated system: A Management Information System shares a large amount of data from multiple departments within an organisation to produce accurate reports. For example, financial data can be used to generate accurate pay slips. Decision Making: An MIS can be used to inform an organisation's decision making by highlighting areas that need improvement within the company. Powerful analysis: An MIS will use large data sets to provide accurate data analysis that can be used in many different ways by an organisation. Trends and patterns can be identified easily. Backup capabilities: Data can be stored centrally and backed up easily if a disaster occurs. Limitations of an MIS: Cost and installation: An MIS is an expensive tool that needs to be professionally set up and requires technical knowledge to maintain. Requires accurate data: If any data is incorrect or out of date then the analysis will consequently be inaccurate . Potentially disastrous decisions could be made as a result of incorrect data. Training: Employees will need to be trained to use the software accurately for maximum efficiency. Managing Information Data Collection Information can be collected in different ways e.g. paper forms, surveys, stock taking and data capture forms in databases. Example: A tennis club can create a form on their website that allows users to apply for membership and fill in key data such as their name, address and telephone number. Storage Collected data must be stored in a secure and easily-retrievable medium . This could be paper, magnetic, optical and cloud storage. Data is most conveniently stored in a database so that information can be added, removed or updated when necessary. Data must be stored securely to ensure it is protected against loss, accidental or via hacking / corruption. Sensitive data should be encrypted so that others cannot view / alter it without authorised access. Information should also be backed up in case the data is lost. Example: The tennis club can store data in a database using cloud storage as soon as a new member enters their information. Using cloud storage allows the tennis club to access that information from multiple access points and they will only pay for the amount of storage that they need and use. Retrieval Using a database to store information allows users to easily access data so that it can be updated or removed. Searches and queries can be easily performed on all tables in a database to show specific values using certain criteria. Example: The tennis club can submit a query in their member database to display all members whose membership will expire in the next month. They can then use that information to email a reminder to those members. Manipulating & Processing After collection and storage, data must be processed so that it is ready for the final stage: analysis. Data can be exported to other software , such as from a database and into a spreadsheet so that it can be manipulated , sorted and visualised . Graphs and charts can be created on data in a spreadsheet so that patterns and trends are easier to identify . Example: Member information in the tennis club can be exported to spreadsheet software that then allows for graph / chart creation using specific values, such as membership expiry date or membership type. Analysis To analyse the data is to see what can be learned from it, so important decisions can be made. Example: Analysing the charts made in the processing stage will allow the tennis club to identify key patterns. For example, they could see when most members sign up during the year and where the members travel in from. Using these patterns the club can then inform future practice. For example, if not many members sign up in August, a sale on membership can be created at this time to entice new members. Or if most members travel in from a certain area of town a bus system might be set up to help those members travel in more often. Q uesto's Q uestions 2.4 - Information Management: 1a. What is the purpose of an MIS ? [2 ] 1b. Describe 3 ways a bank could use an MIS . [3 ] 1c. Describe the benefits and limitations of an MIS . [10 ] 2. A charity for endangered birds (Bird Rescue UK) is creating a survey to send to scientists to find out which birds need protection status and are endangered in the UK. Describe how Bird Rescue UK can use each stage of data management : Data Collection Storage Retrieval Manipulation & Processing Analysis [3 each ] 2.3 - Quality of Information 3.1 - Data vs. Information Topic List

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 reassembles 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 . 4-Layer TCP/IP Model The TCP/IP model is 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 . The four layers are explained below: 4 Allows humans and software applications to use the network e.g. browsers (HTTP /HTTPS ) and email (SMTP ) and file transfer (FTP ). 3 TCP breaks the data down into data packets . This layer makes sure the data is sent and received in the correct order and reassembled at the destination without errors. 2 IP is responsible for addressing and routing data packets . The optimal route for the data to take is calculated in this layer. Also known as the 'Internet Layer '. 1 Ethernet sets out the format of data packets . This layer handles transmission errors and passes data to the physical layer . 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. Describe why network designs are split into layers . [ 2 ] 4. Create a diagram similar to the one above and describe each layer of the TCP/IP Model. [ 8 ] 5. Look at the statements below and name the layer that is being described: a. This layer ensures data packets are sent and received correctly. b. This layer checks for errors in transmission and sets out the data packet format. c. This layer allows software like web browsers to interact with the network. d. This layer uses addresses to ensure data packets take the correct route. [ 7 ] 3.2a - Wired & Wireless Networks Theory Topics 4.1 - Security Threats

Setting up Python Downloading Python If you are using Python in Computer Science lessons, then your school should already have it downloaded and installed on the school computers. It is a good idea to download it on a home computer too so you can practice outside of lessons. Python is free and can be downloaded from the official website. You should download the most up-to-date version of Python 3. Save the file and then run it to start installing. Official Download Page Using Python When you run the Python application, it will open the shell. This window will display the outputs of any program you have created. Do not type into the shell . Click on the File tab then New File to open the editor. Python Shell - This displays the outputs of your program. Do not write directly into the shell . Python Editor - All code is written into the editor. When you want to test a program press the F5 key (or click the Run tab then Run Module ). The first time you test a program, it will prompt you to save the file. Make sure you save it somewhere you will remember - it is a good idea to create a folder named 'Python' where you can keep all your practice programs. The next page looks at actually creating a program but above shows how code has been typed into the editor and then displayed in the shell. You never need to save the shell window. Also, the editor saves automatically every time you run the program. Opening a Saved Program When you want to re-open and edit a file you have created previously double-clicking on it won't work . Right-click on the file and select Edit with IDLE : https://trinket.io/python/76b41b35c5 1 a - Printing ➡