5. The internet and its uses Flashcards

Question

Protocols to transfer data safely

Answer 1

HTTPS SSL TSL - layers are handshake and record

Answer 2

A collection of interconnected networks, not the world wide web as that is a part of the internet

Answer 3

ISPs are companies supplying connectivity to the internet, email services, web hosting and VOIPs. You connect to the Internet service provider that you are contracted with, when you connect to the ISP you become a part of their network. This ISP may connect to a larger network and become a part of that. Every ISP has its own data storage facility.

Answer 4

Internet explorer, google chrome and firefox are all browser softwares. One way to access a particular page is by typing its address into an address bar.

Answer 5

Servers host software or services that you can access. Online storage: Dropbox OneDrive Google Drive

Answer 6

PC > Router > Modem > ISP > Internet router provides access to local area network modem connects to your internet service provider (ISP) - modem no longer used in modern technology ISP connects you to the internet

Answer 7

stands for modulator/demodulator converts digital signal from computer and converts to analogue signal for phone lines a second modem at the receiving end converts the signal back to digital

Answer 8

A router is a hardware device that allows you to connect several devices to a single internet connection (home setting) Many routers have a WAP (Wireless access point) allowing you to create a wireless access point

Answer 9

TCP (transmission control protocol) breaks up messages sent over the internet into packets reassembles packets at the other end detects errors resends lost messages IP protocol - routes the individual packets between sender and recipient

Answer 10

HTTP (hyper text transfer protocol) used for accessing and receiving web pages in the form of HTML files on the internet The protocol requests the web server to upload the requested web page to the users browser for viewing HTTPS (secure protocol) encrypts the information so that it can not be hacked

Answer 11

Each file is broken up into packets Each packet is given a header containing: - IP address its going too (Internet protocol) - IP address it came from - Sequence number of the packet - Number of packets in the whole communication

Answer 12

Every device connected to the internet has an IP address eg. 81. 101. 137. 12 Packets are labelled with the senders and the destinations IP address Packets are sent across the internet along separate routes and reassembled at the end

Answer 13

A PC network has a public and private IP address Public IP belongs to the router on your LAN Private IP is accessible only through the LAN ISPs are allocated blocks of IP addresses Once a message arrives at the router of your LAN it will use the private IP address to identify which device requested information

Answer 14

A media access control address is assigned to each Network interface card by the manufacturer. Computers may have 2, one for ethernet and one for wireless or for a phone wireless and bluetooth Hex value eg. 3B:14:E6:39:0A:2C Every network device in the world has a unique MAC address There are 2^48 possible MAC addresses Role of a MAC address: When you request a web page each router along the way uses the MAC address of the next router to send the data packet to the next leg of its journey.

Answer 15

Uniform resource locator is a web page and all are unique WWW. Domains names (TDLs) .uk , .nz etc

Answer 16

Domain Name system DNs technology allows you to type a URL into your web browser and it translates the web address into an IP address. There are 13 DNS “root” servers worldwide that keep complete database of all names and IP addresses Lower level DNS servers are owned by ISPs and hold parts of the database When a DNS server receives a request not in its database it will pass it on until reaches one with the matching name and IP address

Answer 17

A cookie is a small data file that a web server puts onto your computer when you visit a website Cookies save any data entered such as registration details, passwords and relevant adverts for you as well as web preferences.

Answer 18

User types web address (URL) into browser Browser forwards request to web server to access page Web server acknowledges request and sends HTML source code for the web page to the computer Source code is rendered (translated) into viewable web page

Answer 19

Malware is any software written with malicious intent. Disrupt computers from their work Corrupt files Record key presses and gather information Gain unauthorised access to a computer or files Not all viruses cause harm, but the ones (most) that do: limiting hard disk space and memory destroying or damaging files and data spamming your address book with contacts consuming your internet bandwidth Types of Malware: Spyware, gathers information, installs more spyware, sends information back to spyware author, sells to advertising companies or help with identity theft Adware, irritating pop ups, instals itself on a computer, rarely harms Viruses, small program that replicates by inserting itself in other computer programs - attach them self to existing software programs and infect when you run that program - self replicate Worms, a standalone file that does not need a host program to attach itself to Trojans, a non-self-replicating virus that masquerades as a harmless file that you might want to open Ransomware, malware used to lock your computer or access to your flies for which you are then asked to pay a fee to regain access

Answer 20

A virus can compromise a computer and use the host’s storage and processing power to perform jobs This computer can then become a part of a Botnet network ( a group of computers secretly cooperating to send spam or cause disruption on a much larger scale) Computers in a botnet can: send email spam to other users store and distribute illegal material perpetrate a Denial of Service attack

Answer 21

Denial of service attack Frequently aimed at company or web servers to overload them or make them crash by: - flooding servers with millions of requests - absorbing 100% of its processor time or memory - using all available bandwidth Attempts to make a network or website unavailable to legit users and the motive is often revenge, blackmail or terrorism

Answer 22

Use strong passwords, keep software up to date, and avoid clicking on suspicious links or downloading files of unknown sources.

Answer 23

detects viruses deletes or quarantines infected files commonly finds all malware including adware, spyware, worms and Trojans Works by: holding a dictionary of snippets used in viruses scans new files, downloads, external drives on your computer looks for suspicious codes by comparison keeps a dictionary of know viruses up to date

Answer 24

acts as a filter or barrier between your own trusted network and others only allows certain data packets across that meets set filtering rules

Answer 25

Breaking security defined as unauthorised access to files or data Exploiting weaknesses in websites or security systems to access data Guessing default or common passwords Tricking people into downloading malware to gain access to their computer Logging in as someone else without their permission In order too: pure mischief or a challenge steal money steal or modify information for political reasons, expose wrongdoing or revenge on opposing views

Answer 26

Black hat hackers are illegally hacking with criminal intent White hat hackers ethical hackers employed by companies to deliberately find holes in their own security Grey hat hackers look for wholes in other systems and ask for a payment from those systems

Answer 27

Not hacking Illegally accessing program source code to change it or fool it to: Bypass security or licensing control prevent software from expiring unlock features that otherwise would require a subscription

Answer 28

International standard language that all pages can read and all pages are written in. Webpages, webpage code

Answer 29

In a text file containing the content of the website to be displayed by the browser Uses to govern how to present sections of content Stores locations of images that are to be displayed Stores the location of other websites that are linked to using hyperlinks

Answer 30

HTML controls content and function of a web page Cascading Style Sheets control its style and appearance

Answer 31

open <> and close > Websites are made of a head and body

,

- different headings (main , sub) : emphasis Click here for more info : link placed in middle line, click to access

Answer 32

Define the style at the top between tags h1 {colour:blue; text-align: centre} Everything that falls inside the style tag, that html will adopt that style Sector ==> h1 or other Declaration ==> property and value Property ==> colour or other Value ==> blue or other h1 {colour: blue;} To add a CSS style: Define a style for a particular tag eg. h1 or Define a general style and attribute it to a new name eg. #page Attribute style to a

block: Image file on desktop

Answer 33

− Browser / client sends request to webserver for identification − Web server sends its digital / security certificate − Browser authenticates certificate − If authentic connection, is established any data sent is encrypted − Using public and private key to do this

Answer 34

− Handshake and record protocols − Client/Browser requests secure connection to web server − Browser requests server to identify itself − Web server then provides digital certificate after identification − Browser validates certificate − Browser sends signal to web server to begin transmission − Session key generated − Encryption method is agreed on The handshake protocol is used to exchange all the information needed by both computers in order to establish a secure SSL/TLS connection The record protocol handles the actual data and it’s encryption

Answer 35

Browser sends URL to DNS using HTTP DNS find matching IP address for URL and sends it to the browser Browser requests web server for web pages Web pages are then sent from web server to the web browser Browser then renders the HTML to display web pages Security certificates authenticated, SSL and TSL used to encrypt data sent to and fro

Answer 36

− Acts as mediator between the user’s computer and web server − Allows internet traffic to be filtered − Speed access to information on website using cache

Answer 37

− Encryption key used − Key uses algorithm to scramble data − Data before encryption is plain text − After encryption it is known as cypher text − Same key used to decrypt data

Answer 38

− Key is kept secret, only sender and receiver know − Sender uses same key to encrypt and decrypt − Key has to be sent over internet, can be intercepted − Less safe but fast

Answer 39

− Public and private key mathematically linked − Public key used to encrypt, anyone can see − Private key not transmitted, used to decrypt − Safer process but slower

Answer 40

− Webserver is sent multiple requests, requests flood the webserver at the same time − Webserver crashes / runs slow − Designed to prevent access to e.g. a website // Stops legitimate requests being processed/serviced

Answer 41

Copyright − law/legislation that requires permission to use intellectual property / other people’s work Plagiarism − To claim other’s work as your own − To use other people’s work without consent / acknowledgement − Theft of intellectual property

Answer 42

Lost from Human error, accidentally deleting file Hardware failure Power failure or surge Physical damage, fire or flood Misplacing storage device Prevention Back up data regularly Use surge protection and UPS Keep data in protective case Use verification method for deleting file Follow and educate on correct procedure of ejecting files, saving, etc.

Answer 43

Phishing Pharming Spyware Dos Malware Viruses Worm Rootkit Backdoor

Answer 44

Anti-spyware Scans computer for spyware Removes/quarantines any spyware found Prevent spyware from being installed Onscreen keyboard Key-logger can’t collect data of key press Can’t relay useful info to 3rd party 2 Factor Authentication Extra data sent to device Harder for hacker to obtain data Data has to be entered into same system if entered from remote location not accepted Firewall Can be software or hardware based Monitors incoming and outgoing traffic Allows criteria to be set Blocks access to signal that do not meet criteria Restricts access to specific applications

Answer 45

Anti-virus Scans computer for viruses daily Has a record of known viruses Removes/Quarantines any virus found Warns user of virus Checks data before downloaded Prevents download of virus found Firewall/Proxy server Monitors incoming and outgoing traffic Allows setting of criteria Checks if traffic meets criteria Blocks traffic that does not meet criteria

Answer 46

Firewall/Proxy server Monitors incoming and outgoing traffic Allows setting of criteria Checks if traffic meets criteria Blocks traffic that does not meet criteria Passwords Use long and more random passwords Change it regularly Lock after a set attempts Biometrics Data needed to enter is unique to individual Hard to replicate Lock after set attempts 2 Factor Authentication Extra data sent to device Hard for hacker to obtain Data entered needs to be in the same system, if attempted from remote location it’s not accepted

Answer 47

Phishing − Legitimate looking email sent to user − encourages user to click a link that directs user to a fake website − User encouraged to enter personal details into a fake website // designed to obtain personal details from a user Pharming − Malicious code/malware is downloaded without users’ knowledge − That re-directs user to fake website (when legitimate URL entered) − User encouraged to enter personal details into a fake website − Designed to obtain personal and sensitive details from a user

Answer 48

Free software- * Type of software licence * Free of charge * Normally distributed without the source code * Can legally share / copy * Cannot legally modify code * Cannot resell Freeware- Owner has copyright for software but can be given away for free Shareware- Often a trial version of full software, fee required for full access

Answer 49

Legal protection person can obtain to provide protection against their work stolen

Answer 50

Hacking − When a person tries to gain unauthorised access to a computer system − Data can be deleted/corrupted by hacker Malware − A software program designed to damage data / disrupt the computer system − Replicates itself and fills the hard disk Virus − A program that replicates itself to damage/delete files

Answer 51

-When someone alters a program source code usually for a backdoor (by disabling computer security software)

Answer 52

illegally gaining access to a computer system

Answer 53

Curiosity Financial Gain Malicious Hacktivism Military

Answer 54

Changing a program’s source code to be used for another use (illegal)

Answer 55

Software which tracks keylogs and through this can find out passwords.

Answer 56

Antispyware

Answer 57

User clicks on a link from an email or website When clicked spyware is downloaded Monitors users activity and relays it back to author Keypresses can be analysed to find passwords Common key logs allow password to be found

Answer 58

Program that replicates itself Deletes or corrupts files Ransomware a new form of virus

Answer 59

Fake email sent that looks legitimate User clicks on link in the email User redirected to fake website Often used to try and steal financial details How to avoid – Don’t click on links from unknown emails

Answer 60

Malicious code stored on a computer Redirects user to fake website to steal users data How to avoid – check the URL is as expected

Answer 61

Message given to browser by webserver Stored in a text file Stores detail about users preferences on a website Message sent back to server each time that page is requested

Answer 62

Enable logon information to be kept Provide customized pages for the user Enable target adverts Enable one-click purchasing with shopping carts Be able to distinguish between new and repeat visitors

Answer 63

Accidental Deletion Malicious – virus Hardware failure Software failure Natural disaster

Answer 64

Set data to read only Use correct shut down procedures Use correct procedures when removing portable storage devices Backup

Answer 65

Prevents unauthorized access Acts as a filter for incoming/outgoing data Checks data meets criteria Logs incoming and outgoing traffic Blocks access to specified IP addresses

Answer 66

Compares virus signature against a database of known virus signatures Removes any viruses

Answer 67

Keeps user IP address secret Prevents direct access to a web server Filters traffic

Answer 68

Voice recognition Facial Recognition Thumbprint

Answer 69

Text passwords easier to hack than biometrics - Biometric passwords are unique and can’t be shared

Answer 70

Encryption - SSL

Answer 71

Uses encryption Uses SSL Uses digital certificates – contains public key Makes use of public and private keys Data is meaningless without the key

Answer 72

Protocol end in s e.g. https Padlock on some browsers Colour of address bar changes

Answer 73

Web browser connects to the website Web browser requests web server to identify itself Web server sends browser a copy of its SSL certificate Browser checks the certificate is trustworthy and sends message back to server Server acknowledges message and SSL session begins

Answer 74

Record - Handshake

Answer 75

Contains the data being transferred - Can be used with or without encryption

Answer 76

Website and client authenticate each other - Encryption algorithms used to establish secure session

Answer 77

Possible to extend TLS using new authentication methods TLS can make use of session caching TLS separates handshake and record protocol

Answer 78

Before encryption it is plain text Text encrypted using an algorithm Text encrypted using a key Encrypted text called cypher text Key transmitted separately from text Key used to decrypt the cypher text

Answer 79

Private key and Public key needed Public key given to everyone Private key only known by the computer user Encryption keys generated using a hashing algorithm Different keys

Answer 80

Text encrypted using encryption algorithm Text encrypted using a key Key transmitted separately from the text Key used to decrypt the text

Answer 81

-Used to verify that data comes from trusted source

Answer 82

-Uses the same key to encrypt and decrypt data

Answer 83

Takes message or key and translates it into string of characters Usually shown in hex notation Length depends on algorithm used Same hashing algorithm needed to decrypt

Answer 84

Large number of requests sent to server at once Designed to flood a server with useless traffic Server will come to a stop trying to deal with the traffic Prevents users gaining access to the web server

Answer 85

Free software Freeware Shareware

Answer 86

Can use for any legal purpose you wish Can study and change the source code Can pass on to other people Must not be used to infringe copyright laws by copying existing software

Answer 87

Can download and use free of charge - Cannot view or modify the source code e.g. Skype

Answer 88

Can use for a trial free of charge Need to pay once the trial is over Often trial version missing key features Protected fully by copyright laws Cannot modify code or distribute the software

Answer 89

the act of gaining illegal access to a computer system

Answer 90

the editing of program source code so it can be exploited/changed for a specific purpose

Answer 91

program code that can replicate/copy itself with the intention of deleting/corrupting data/files or causing the computer to malfunction

Answer 92

sending legitimate lookng emails to encourage uses to give out personal data

Answer 93

malicious code installed to redirect uses to a fake website

Answer 94

gathers data by monitoring keypresses on user’s keyboards

Answer 95

pieces of data that allow detection of web pages viewed by a user and store their preferences

Answer 96

this could be due to accidentally deleting a file or to a malicious attack from viruses or hacking

Answer 97

examines traffic between user’s computer and a public network - can help prevent viruses or hackers entering a user’s computer

Answer 98

allows data to be sent and received securely across a network

Answer 99

a protocol that is designed to ensure that no third party may eavesdrop or tamper with any message

Answer 100

a secret key which makes a message unreadable unless the recipient also has the decryption key

Answer 101

a form of encryption requiring both a public and private key

Answer 102

used to verify that data comes from a trusted source

Answer 103

an attempt at preventing users from accessing part of a network

Answer 104

users have the freedom to run, copy, change or adopt free software

Answer 105

software which users can download free of charge

Answer 106

users are allowed to try out shareware for a trial period

Answer 107

lead to identity theft and loss or corruption of data

Answer 108

using strong passwords using firewalls

Answer 109

for malicious purposes (such as modifying legitimate software to do something like redirect a user to a fake website)

Answer 110

it is hard to do software engineers need to make the act of breaking into the software nearly impossible (make it difficult to identify back doors)

Answer 111

run slow crash cause some software to run abnormally

Answer 112

running anti-virus software don’t open emails/software from unknown sources

Answer 113

messages containing poor spelling/grammar asks for personal information unrealistic threats/promises made

Answer 114

anti-spyware software can identify and remove pharming code on the hard drive

Answer 115

the act of locating and using wireless internet connections illegally can lead to stealing of internet time/bandwith

Answer 116

use of WEP (wired equivalent privacy) encryption complex passwords firewalls

Answer 117

Networks are connections between nodes (devices) to share resources. Being connected to a network can be dangerous because there are more access points.

Answer 118

Personal Area Network (PAN) Local Area Network (LAN) Wide Area Network (WAN)

Answer 119

A personal area network is within the range of an individual, +- 10m. Examples are: Bluetooth

Answer 120

It is a network that connects devices close to one another, like in the same house; school; office.

Answer 121

A wide area network is a network over a broader, geographic area. For example, an internet connection is given by an ISP. The internet is a WAN made up of individual LANs.

Answer 122

In a Client-Server Network, every device is either Client or Server. A client will request resources from the server. When a resource is wanted, the client establishes a connection with the server over the network Servers backup and store data centrally, although expensive and difficult to run. It is centralized

Answer 123

A P2P network is decentralized. Each node is equal in responsibility and can work as both client and server.

Answer 124

Latency The Delay, Speed of Signals Bandwidth Max rate of Data Transfer (bps) Error Rate How often data is corrupted How often data must be resent

Answer 125

Wired connections are generally faster Though Bandwidths must be taken into account, but is shared across a network Wireless range signals degrade quickly and can be blocked Signals at the same frequency can interfere, leading to dara collisions Bus topology have higher error rates

Answer 126

They are rules that must be accepted to devices can be compatible and reliably communicate.

Answer 127

They are developed in layers, each responsible for a different part of the process of communication. Layers break the process down into managable self-contained parts. Easier to develop because it is focused on one aspect easier to develop standards changing one layer won’t affect another

Answer 128

It has 4 layers: Application Layer HTTP/S; FTP; SMTP; IMAP & POP; DNS Transport Layer TCP; UDP Network Layer IP Link Layer Ethernet; Wifi

Answer 129

The application layer is where network applications can operate, e.g: Web Browsers, Email Clients

Answer 130

This layer sets up communication between the two hosts, and includes the agreed rules.

Answer 131

This layer addresses and packages data, and routes it.

Answer 132

This is where the hardware and drivers operate.

Answer 133

It is a standardised family of protocols. Ethernet works at the link layer it describes how devices on the same netwoek degment format data and transmit it

Answer 134

It is a form of wireless transmission, radio waves EM waves are categorised on frequency A channel represents a small frequency range, designated by number Frequency overlap can cause interference. Data is encrypted using WAP

Answer 135

TCP is the transmission control protocol, which runs in the transport layer. It deals with the connection between devices, it: receives data from the application layer receives the packets from the network layer splits data into packets reassembles them sends an acknowledgment

Answer 136

It is the internet protocol, it addresses packets with the source and destination’s IP address, and works at the network layer. The IP removes the IP addresses when the packets are no longer needed.

Answer 137

It is the hypertext transfer protocol, a hypertext is a type of text with links. HTTPS is HTTP with encryption through certificates. HTTP is used to access a webpage from a web server, the process goes as: The client requests a message the webserver gives a response

Answer 138

The file transfer protocol is of the application layer, which handles file uploads and downloads. HTTP transfers viewable content whilst FTP transfers data.

Answer 139

SMTP POP3 IMAP

Answer 140

The simple mail transfer protocol is of the application layer.. it handles outbound. It sends the email to a mail server, and then to the internet. SMTP servers have user databases.

Answer 141

it is post office protocol, this is from the internet, mail server to the client. It doesn’t keep client and server in sync. When the mail is downloaded, it is deleted from the server.

Answer 142

It is internet message access protocol, where it keeps both client and server synced in which the mail is copied instead of downloaded. For the mail to be deleted from the server, you must contact the client.

Answer 143

Topologies are the arrangement of the nodes and connections in a network. Bus Star Mesh Ring

Answer 144

All clients, serbers and resrouces are connected to one medium, the bus. When a node communicates, the data is transmitted down the bus. All drivers receive it but only the intended recipient accepts and processes the message. There are terminators on both ends, which are resistors. They prevent data from reverberating

Answer 145

Advantages: Cheaper, because less wires Disadvantages: If the main bus fails, all fails Prone to data collisions in high traffic, which slows the data down.

Answer 146

In this topology, each device is connected to two other devices, forming a ring for messages to travel around. The nodes take turns sending data, data is sent one direction through each device until the intended recipient receives it.

Answer 147

Advantages: Simple, less wires, cheaper. Disadvantages: All nodes must be one for the data to be sent.

Answer 148

Most home networks uses this topology, as each node is connected to the central connection point.

Answer 149

Advantages: Data goes immediately to recipient Disadvantages: If the central connection point fails, network stops.

Answer 150

In a full mesh, every node is connected to every other node. In a partial mesh, there are simply many connections between nodes. A mesh could be used as a backup mechanism, called the redundancy as it is needed but used as an alternative route.

Answer 151

Advantages: Provides backup should one route fails Direct links to recipient. Disadvantages: Expensive, many wires Complicated Can’t add one device without connecting to every other device.

Answer 152

It is the processes, practices, and technologies designed to protect networks from attacks, damages, or unauthorized access.

Answer 153

It can happen internally and externally.

Answer 154

Physical Security CCTVs, Case Locks, Disabling USB Ports Cloud Security Ensure the cloud servers you use are safe

Answer 155

Validation Ensuring that data is correct and secure before processing Authentication Ensuring that an entity is genuine, like users, product authentications.

Answer 156

Unpatched Software Misconfigured Access Controls Social Engineering Phishing Shoulder Surfing USB devices Portable Digital Devices Eavesdropping Malicious Code, malware basically Commercial Analysis tools

Answer 157

It is basically just un-updated software, which may have some protection holes.

Answer 158

It is when an entity has permission to access something that they’re not supposed to.

Answer 159

It is the usage of sending emails from a ‘verified’ entity that contains malicious links that can lead to websites that download malware.

Answer 160

Someone staring at you when you type in important information.

Answer 161

It is malware like: viruses spyware things like that

Answer 162

Penetration Testing Ethical Hacking

Answer 163

It is basically stimulating an attack to find any weaknesses. For example, entering a random username and password just to see if it can access the site. It is normally done by an external entity.

Answer 164

White-box pen test Inside attack, where attacker has some knowledge of the system Black-box pen test Outside attack, hacking

Answer 165

Hacking is finding and exploiting vulnerabilities, it is only ethical when done in a testing context. There are kinds identified by white/black/gray hat hackers. For it to be ethical, it must: Have permission Be worked on securely notify admins when weaknesses are found

Answer 166

They monitor network traffic and filter data packets based on agreed rules. Routers and dedicated hardware contain firewalls, they can: Block Packets Connections from certain regions

Answer 167

Header Data Trailer

Answer 168

Packet filtering is done by looking at the addresses on the packet header. (first generation) Stateful Inspection is done by looking at the data context. (second generation)

Answer 169

Design Stage Planning Audit Trails Securing Operating Systems Good Programming Practices

Answer 170

It is threat modeling, basically just analysing vulnerabilities from a theoretical attacker’s view.

Answer 171

These are system records kept, which can trace security issues.

Answer 172

Limit User Accounts Directory Permissions Strong Passwords Limit automatic softwares Install patches and update new versions

Answer 173

It is the worldwide collection of networks that use the internet protocol suite, TCP/IP.

Answer 174

It is the collection of web pages hosted on web servers.

Answer 175

The WWW is the resources on the internet, whilst the internet is the hardware.

Answer 176

They are addressers to specific web resources.

Answer 177

Network Protocol → Domain Name → File Names

Answer 178

It is an address that uniquely identifies devices on a network. IP addresses are denary, but also uses 8 bit binary, it is: assigned by the ip temporary, like in ram defines geographic locations

Answer 179

Data transverses throughout international servers.

Answer 180

The international routers uses the destination IP address of the packet to identify where to send the packet. Routing algorithms will determine the best route to get there.

Answer 181

Packet Switching

Answer 182

There is no fixed paths, but each packet can take different routes, packet heads contain packet numbers, MAC and IP addresses as well as the protocol. The trailer has a validation checks.

Answer 183

internet service protocol are companies that provide users with access to the internet

Answer 184

IP address is used to identify a device (on the Internet / network) 32-bits changes as you move because static or dynamic ipv4 and ipv6 assigned by ISP address is unique for given Internet session 256.342.34.235

Answer 185

hardware/physical address unique number that identifies a device (connected to the Internet) address is made up of manufacturer id + serial number of device address is allocated by the manufacturer 48 - bits 1st half is manufacturing 2nd half is serial number does not change/ static only part on Number identification card

Answer 186

a set of rules obeyed when transferring files across the internet

Answer 187

access protocol domain name file name

Answer 188

A global infrastructure of interconnected networks

Answer 189

All of the web pages that are accessible via the Internet.

Answer 190

Uniform Resource Locator Each web page has its own unique text-based address

Answer 191

Domain Name

Answer 192

Web page / file name

Answer 193

A set of rules for communication between devices. It allows equipment from different suppliers to work together

Answer 194

HyperText Transfer Protocol

Answer 195

The standard transmission protocol of the Web

Answer 196

The standard transmission protocol of the Web

Answer 197

Any data you enter into the site is sent in plaintext and is susceptible to hacking

Answer 198

HyperText Transfer Protocol Secure

Answer 199

A secure protocol that encrypts any data sent between the website and your browser so that it can’t be understood if intercepted.

Answer 200

Storing bookmarks and favourites Recording user history Storing cookies Providing navigation tools Allowing use of multiple tabs Providing an address bar

Answer 201

Hypertext Markup Language The standard markup language for creating web pages

Answer 202

A public address that is unique to each device. Every networked computer has an IP address

Answer 203

It converts a URL address into an IP address This means that a browser on a client machine can make a request to the correct web server hosting that web page

Answer 204

It converts a URL address into an IP address This means that a browser on a client machine can make a request to the correct web server hosting that web page

Answer 205

It passes the request to a more authoritative DNS server. An error is sent back if no match is found.

Answer 206

Text files with small pieces of data

Answer 207

They are used to track user preferences, hold items in a shopping cart, store login details and other personal details

Answer 208

They are created and replaced each time a user visits a website

Answer 209

They are created and saved on the first visit and retained until they expire

Answer 210

The retailer can send personalised email advertisements to customers The retailer can analyse quantity and value of sales/advertising The retailer can implement one-click purchasing

Answer 211

They will not need to remember login details They can use one-click purchasing Websites will remember their personal customisations

Answer 212

Any money-like asset that only exists in digital form. It is exchanged digitally with no physical banknotes or coins in circulation

Answer 213

Can transfer funds without the intervention of private banks Reduced transfer fees and sped-up transaction completion time Improves security and anonymity

Answer 214

A digital ledger –> a time-stamped series of transaction records sequentially linked in a chain, tracking the movement of a digital currency

Answer 215

Each new transaction is added onto a chain of transaction blocks Each block will carry the user’s ID number and a reference to the previous block. This is known as a hash total and is calculated with a hashing algorithm A change of data in one block will create a ripple effect of incorrect hash totals The blockchain will be stored on multiple different servers, and if one chain doesn’t match all others, it will be rejected

Answer 216

currency (a system of money) that exists in electronic form only;

Answer 217

a form of digital currency that uses a chain of decentralised computers to control and monitor transactions

Answer 218

the protection of data/information by use of coding; it usually involves encryption and decryption

Answer 219

is a digital ledger, that is a time-stamped series of records that cannot be altered

Answer 220

a digital record of the date and time that a data block is created in blockchain networks

Answer 221

Data Hash value Previous hash value time stamp

Answer 222

Because altering one block will change its hash value and break the link to the following blocks - invalidating the whole chain.

Answer 223

Automated or manual attempts to gain unauthorised access to programs or data

Answer 224

Firewall to block access by unauthorised devices

Answer 225

Automated or manual attempts to gain unauthorised access to secure areas by trying all possible password/key combinations

Answer 226

Strong passwords Limited attempts allowed

Answer 227

Data may be intercepted during transmission, but physical theft can occur where storage devices or data files are left insecurely

Answer 228

Encryption Passwords Physical locks

Answer 229

Software that hides on your computer and records your activities to send back to a third-party for analysis

Answer 230

Anti-malware Anti-spyware software

Answer 231

Phishing emails redirect a user to a fake website where they trick the reader into divulging confidential information such as passwords that can be used fraudulently

Answer 232

Network policy Firewall User awareness of phishing ‘clues’

Answer 233

Sends the user to a fake website that looks like the real thing. The user types in a legitimate address and is redirected to a fake website

Answer 234

Checking the URL Making sure the site says HTTPS, not HTTP

Answer 235

Checking the URL Making sure the site says HTTPS, not HTTP

Answer 236

Malicious software written to cause inconvenience or damage to programs or data

Answer 237

A program that is installed on a computer without the user’s knowledge or permission with the intent of doing harm. It includes instructions to replicate automatically on a computer

Answer 238

A program that is similar to a virus, except it cannot self-replicate

Answer 239

Software that runs on a computer checking all files for known viruses It must be updated regularly

Answer 240

A program that masquerades as having one legitimate purpose, but it actually has another

Answer 241

A link is spread by email The user is invited to click on a link for an everyday purpose This link then executes a program which gives the controller unauthorised access to the computer

Answer 242

A form of malware that encrypts a victim’s files.

Answer 243

A ransom is demanded from the attacker in return for instructions on how to decrypt the files

Answer 244

A malware that displays onscreen advertisements. It is not always dangerous, but could redirect the browser to an unsafe site

Answer 245

Distributed Denial of Service

Answer 246

A malicious attempt to disrupt the normal traffic of a targeted server with a flood of Internet requests

Answer 247

Multiple interconnected devices in different locations establish a botnet The attacker is then able to direct the attack by sending remote instructions to the bots to send requests to the target’s IP address The server becomes overwhelmed, and genuine requests cannot be handled The server fails or times out

Answer 248

A firewall can filter through requests to separate the genuine and fradulent requests

Answer 249

Pre-recorded characteristics to authenticate authorised users of a system/device

Answer 250

Facial recognition Iris and retina scanners Fingerprint recognition Voice recognition

Answer 251

Two authentication methods performed one after the other to prove someone’s identity

Answer 252

These updates will keep applications and the OS up-to-date. This enables bugs and security flaws in the software to be fixed with a patch

Answer 253

Secure Socket Layer

Answer 254

Provides a secure channel between two computers or device operating over the internet

Answer 255

SSL is used to secure communication between a web browser and a web server. It will then use an HTTPS address for the website Similar to asymmetric encryption

Answer 256

Control what information about them is shared on a social media platform. A user can control who has access to what they post, and who can see their full profile

Answer 257

Any machine that checks and forwards traffic between networks or protocols.

Answer 258

It’s an intermediary server that separates end-user clients from their destination site. It can provide varying levels of functionality, security and privacy.

Answer 259

Accidental damage could occur, such as file corruption and human errors Malicious actions may be taken by other people to view, delete, copy and/or corrupt data without authorisation

Answer 260

Secure Socket Layer Provides secure connection between internet browser and websites Allows transmission of private data Indicated by padlock sign on the web browser (sometimes the address bar is green) Uses two keys to encrypt the data: a public key known to everyone and a private key only known to the recipient URLs that require an SSL connection start with ‘https’ e.g. e-commerce shops use SSL to keep credit card details secret

Answer 261

A type of encryption where the same key is used to encrypt and decrypt the message. This differs from asymmetric (or public-key) encryption, which uses one key to encrypt a message and another to decrypt the message. Increasing the length of the key increases the strength of the encryption.

Answer 262

A computer network is a number of computers linked together and able to communicate using certain protocols. Networked computers can share resources including hardware, software and data. Most computer networks have at least one server.

Answer 263

Advantages: Easy, efficient communication by emails, instant messaging, telephony, video conferencing, chat rooms, etc. Ability to share files, data and information (beneficial for large organizations to organise data and allow certain people access to data) Saves costs by sharing hardware (e.g. printer) and software (site licences are likely to be cheaper than buying several standalone licences) Sensitive files and programs on a network can be password protected. Rapid sharing and transferring of files, saves time while maintaining the integrity of files

Answer 264

Disadvantages: Possibility of breakdowns and loss of resources Expensive to build Managing a large network is complicated, requires training and a network manager usually needs to be employed Viruses can spread to other computers in the network Danger of hacking, particularly with wide area networks. Security procedures are needed to prevent such abuse, e.g. a firewall.

Answer 265

Pre-agreed signals, codes and rules that are used between two or more computer systems to exchange data and information

Answer 266

The internet is a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized communication protocols. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies. The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support email.

Answer 267

A piece of software used to view and download web pages and various types of files such as text, graphics, sound and video.

Answer 268

Displaying web pages Browsing back and forward between web pages Customisation of basic options such as your homepage, content censorship and security preferences Bookmarking History Offline browsing Downloading Search engines E-mail

Answer 269

A combination of computer and software that provides a service to other client computers or application programs.

Answer 270

This is a computer with specific web server software that provides clients with access to web pages

Answer 271

Client devices send requests for services, e.g. printing or retrieval of data to specific server devices that perform the requested processing

Answer 272

A company that provides you with access to the Internet, usually for a fee. The most common ways to connect to an ISP are by using a phone line (dial-up) or broadband connection (cable or DSL). Examples : STC, Mobily, Zain, etc.

Answer 273

Hypertext transfer protocol (http) is the underlying protocol used by the World Wide Web which defines (1) how messages are formatted and transmitted, and (2) what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.

Answer 274

Hypertext transfer protocol over secure (https) is a secure method of accessing or sending information across a web page. All data is encrypted before it is sent, preventing anyone from understanding that information if intercepted. Because data is encrypted over https, it is slower than http, which is why https is only used when requiring login information or with pages that contain sensitive information such as an online bank web page.

Answer 275

HyperText Markup Language (HTML) is the markup language used in creating web pages on the World Wide Web. A document Markup Language is a modern system for annotating a document in a way that is clearly distinguishable from the text.

Answer 276

Structure consists of the mandatory parts of an HTML document plus the semantic and structured markup of its contents. Presentation is the style you give the content. In most cases presentation is about the way a document looks, but it can also affect how a document sounds – not everybody uses a graphical web browser. Separate structure from presentation as much as possible. Ideally you should end up with an HTML document which contains the structure and content, and a separate CSS file which contains everything that controls presentation.

Answer 277

IP: internet protocol TCP: transmission control protocol, it performs handshakes, packet sequencing, flow control and error handling Extremely popular protocol on which the internet is based Data is broken up into independent small packets Size of the packet is up to the network designer (typically they start from 512 bits upwards)

Answer 278

An Internet Protocol (IP) address is a unique identifier for computers on the internet Each device that is part of a network using TCP/IP (normally internet) has to have an address to be able to identify itself and be allowed to use the network. Static IP addresses are fixed, dynamic addresses change frequently.

Answer 279

IPv4: Uses 32-bit addresses There are not enough addresses for all computers on the internet, as some addresses are reserved for certain purposes or for certain companies IPv6: Uses 128-bit addresses Solution to the problem of not having enough addresses

Answer 280

Four numbers separated by periods (in the form w.x.y.z.) Each number is an 8-bit binary number between 0 and 255, making up a 32-bit address Each number group in the address sub-divides the network to which the computer is connected with the final number being the actual computer. 11000000.10101000.00000000.11001011 192.168.0.203 Network address Host address

Answer 281

Stands for Media Access Control Also known as a hardware address or physical address Uniquely identifies each node of a network (A node is a processing location – a network adapter or any device with built-in network capability) While an IP address can potentially be assigned to any device, a MAC address is ‘burned into’ a given device from the factory – it is hard-coded into the network interface card (NIC) by the manufacturer

Answer 282

Uniquely identifies an adapter on a LAN Allow communication between devices on a local network by making it possible to reliably distinguish one computer from another Increase security as cannot be impersonated If you set up a WiFi one of the things you can do to improve security is to only allow devices with certain MAC addresses to connect to the network. When a data packet is being sent out to a station that is on the same network LAN segment, only the MAC address is needed.

Answer 283

Six pairs of hexadecimal digits (48 bits in length), usually separated by colons or dashes 01:1F:33:68:BC:14 OR 01-1F-33-68-BC-14 Organisational Unique Identifier (OUI) *Identifies the company that manufactured or sold the product Universallv Administrated Address (UAA) *Specific to the device, like a serial number

Answer 284

Six pairs of hexadecimal digits (48 bits in length), usually separated by colons or dashes

Answer 285

A message given to a Web browser by a Web server. The browser stores the message in a text file. The message is then sent back to the server each time the browser requests a page from the server. They are used: to enable logon information to be kept on the computer to provide customised pages the next time the user logs on, e.g. customised adverts to implement shopping carts and one-click purchasing to be able to distinguish between new and repeat visitors to the website

Answer 286

A computer that is not connected to a network

Answer 287

An arrangement of two or more computers that are connected together for the purpose of sharing resources and data

Answer 288

A network of physical objects that use sensors, actuators, embedded systems and wireless technology such as WiFi and bluetooth to collect and exchange data with no human interacion

Answer 289

Voice internet protocol

Answer 290

Local Area Network

Answer 291

Wide Area Network -Bank / hotel chain network

Answer 292

Wireless Local Area Netwrok - Hand held scanners

Answer 293

A computer connceted to a network used to coordinate (store and share) huge amounts of data

Answer 294

The time it takes for a message to transfer (ms). AkA ping

Answer 295

An interconnected network or network of networks. Most networks are part of the internet. Consists of multiple cables or links that connect countries together, and can be though of as the backbone.

Answer 296

Breaking down a large amount of data into small packets, each packet is independent from one another Each packet is tagged with: Source address Destination address Sequence number of the packet total number of packets being sent

Answer 297

Manages communication on the network. Can have a built-in wireless access point (WAP)

Answer 298

Transmission Control Protocol Responsible for delivering data to a given address

Answer 299

Modulator / Demodulator

Answer 300

Hyper Text Transfer Protocol

Answer 301

Simple Mail Transfer Protocol

Answer 302

A Network topology is the arrangement with which computer systems or network deveices are connected to each other

Answer 303

In a bus topology, all nodes in the network are connected directly to a central cable that runs up and down the network

Answer 304

Each node is connected with two other deveices

Answer 305

All nodes indirectly connect to each other through 1 or more switches. The switch acts as a central point through which all communications are passed.

Answer 306

There is no central connection point. Instead each node is connected to at least one other node

Answer 307

Easy to install -Cheap to install

Answer 308

-If the central cable fails the whole networks fails and stops working

Answer 309

No data collisions, as the data only flows in one directions

Answer 310

If the main cable fails, the network fails

Answer 311

If a cable fails, the whole network will not fail and other computers can still work High performance as there are no data collisions

Answer 312

It is expensive to build as it requires more hardware such as switches and wires

Answer 313

Manages a large amount of data as computers can trasnmit data simultaneously If a cable fails, the network still works

Answer 314

-It is expensive to build - It requires much more time to repair or build

Answer 315

Internet protocol Responsible for obtaining the address to which data is sent. A set of rules that govern data transfer in the internet

Answer 316

Layered protocol stack Collection of protocols It sets how data should be formatted and transmitted across networks

Answer 317

Holds and shares web pages

Answer 318

Holds and maintains user files

Answer 319

Handles emails between users

Answer 320

File size / time

Answer 321

A computer that is not connected to a network

Answer 322

An arrangement(or group or setup) of two or more computers that are connected together for the purpose of sharing resources and/or data.

Answer 323

A network of physical objects that use sensors, actuators, embedded systems and wireless technology such as WiFi, Bluetooth and Zigbee, to collect and exchange data, with minimal or no human interaction.

Answer 324

Voice of Internet Protocol

Answer 325

Local Area Network Example: - School network

Answer 326

Wide Area Network Example: - Bank network

Answer 327

Wireless Local Area Network Example: - Hand held scanners

Answer 328

A computer connected to a network used to coordinate(store and share) vast amounts of data.

Answer 329

The time it takes for a message to transfer (ms). Also known as ping.

Answer 330

An interconnected network or network of networks. Most networks are part of the internet. Consists of multiple cables or links that connect countries together, and can be though of as the backbone.

Answer 331

Breaking down a large amount of data into small packets, each packet is independent of one another. Each packet is tagged (has a header) with the recipient and source IP, checksum and a sequence number for the packets to be put back in order at the destination and checksum

Answer 332

A computer connected to a network used to coordinate(store and share) vast amounts of data.

Answer 333

A Network Topology is the arrangement with which computer systems or network devices are connected to each other.

Answer 334

In a bus topology, all nodes in the network are connected directly to a central cable that runs up and down the network. Advantages: - Cheap since little cabling needed - It still works if a node fails - Easy to add extra devices Disadvantages: - If the central cable is damaged the network stops working - More devices, slower since more collisions - All nodes can access all traffic can be security risk

Answer 335

In a ring topology network, each node is connected to two other devices.

Answer 336

In a star topology, all nodes indirectly connect to each other through one or more switches. The switch acts as a central point through which all communications are passed. Advantages: - Still works if a node fails - Damaged cable doesn’t stop the network from working - Data traffic only sent to intended recipient, secure - Easy to add extra nodes Disadvantages: - If central node fails, network stops working - Network capacity depends on central node’s capacity - Many cables, expensive and difficult to set up

Answer 337

In a mesh topology, there is no central connection point. Instead, each node is connected to at least one other node. Advantages: - Very fault tolerant, if a connection fails, message is re-routed - Nodes can be added/removed without having take network offline - Very scalable - Very high performance, each node is connected to many other nodes Disadvantages: - Many cables, difficult and expensive to set up

Answer 338

Manages communication on the network. Can have a built-in wireless access point (WAP).

Answer 339

Transmission Control Protocol Responsible for delivering data to a given address (packet switching) Transport layer

Answer 340

Modulator/Demodulator

Answer 341

Hyper Text Transfer Protocol Application layer

Answer 342

Simple Mail Transfer Protocol Application layer

Answer 343

Internet protocol Responsible for obtaining the address to which data is sent. Internet layer

Answer 344

Layered protocol stack (Application layer, Transport layer, Internet layer, Link layer) Collection of protocols It sets how data should be formatted and transmitted across networks

Answer 345

Holds and shares web pages

Answer 346

Holds and maintains user files

Answer 347

Handles emails between users

Answer 348

Access control: Ensures that only authorised users can access the network and its resources Authentication (User management) : Ensures that users can only access data relevant to them File permissions: Prevents misuse: deleting/copying data, installing software Physical security: Prevents damage to hardware Firewall: Acts as a barrier between an organisation’s internal network and the internet. Inspects incoming and outgoing data traffic and decides what data to allow through

Answer 349

Business success: data on the network is vital for running an organisation, it might fail if comprimised Privacy: data on the network might be sensitive Financial: the data might be financially valuable

Answer 350

Cloud data centres attract many attacks due to the vast amount of information stored, sensitive data is best stored locally.

Answer 351

Looks for weaknesses in software and systems by trying to penetrate into them so that they can be addressed.

Answer 352

Used to test a computer system or network in order to find vulnerabilities

Answer 353

Exploiting human behavior. The attacker will ‘engineer’ a situation where the target individuals give away confidential information

Answer 354

Someone can exploit a vulnerability in an unpatched (unfixed) software that still has that vulnerability

Answer 355

Prevents infection by malware by searching for it and destroying it

Answer 356

Scambles data for anyone who doesn’t have the key to unscramble it.

Answer 357

Uses two different keys Every user has two keys (public and private) A message encrypted with a public key can only be decrypted with its private key

Answer 358

Uses one key Encrypts and decrypts data using the same key Both ends of the transmission must know the exact shared key

Answer 359

Ethernet Wi-Fi

Answer 360

FTP HTTP HTTPS SMTP POP IMAP

Answer 361

Post Office Protocol Used by a client to retrieve emails from a mail server, message deleted on download, it will be stored on the device it was read/downloaded from

Answer 362

Internet Message Access Protocol Similar to POP but messages can be read and stored on the message server. The message left on the server on read. Hence accesible from any device

Answer 363

Checksum for package computed before leaving the computer Checksum added to the header At recipient, checksum is re-computed If don’t match, re-send request is sent back

Answer 364

Computer networks allow computers and devices to share data. This includes: 1. computer-to-computer communication 2. mobile phone networks 3. computers communicating with devices such as printers, mice and keyboards 4. smart televisions 5. tablets and media players downloading videos and music and playing them through external devices such as speakers and digital projectors.

Answer 365

Local Area Network

Answer 366

Computers in a site such as an office building use an LAN to connect with each other.

Answer 367

An LAN is a computer network for data transmission within a small geographical area such as a home, office or school or a group of buildings on a site.

Answer 368

Wide Area Network

Answer 369

WANs are used for connecting LANs over a large geographical area.

Answer 370

A WAN is a network that connects separate LANs over a large geographical area. This ensures that computers in one location can communicate with computers and users in other locations.

Answer 371

Client-server networks and peer-to-peer networks

Answer 372

Peer-to-peer networks are used to connect a small number of devices, for example in a home or office where there are just a few users.

Answer 373

easier to set up and maintain cheaper

Answer 374

more expensive to set up and maintain as a more powerful computer is required to act as the server and network software is required specialist knowledge is needed to administer the network

Answer 375

The computers that control access to the network

Answer 376

The computers on which the users work - computers that act as a desktop for the users and which relies on a server for its operations.

Answer 377

In a client-server network there are two types of computers: the computers that control access to the network (servers) and the computers on which the users work (clients). From the client machines, the users log into the network servers in order to be able to access programs and peripherals to save data on the servers. The server is therefore responsible for the security of the network, expecting users to log in with a username and password. As all files are stored on the server the data can be backed up centrally.

Answer 378

True. The computers are simply connected together without any one computer having superiority over the others.

Answer 379

In a peer-to-peer network, the computers are simply connected together without any one computer having superiority over the others. All of the computers on a peer-to-peer network are equal. Through sharing rights granted by the users any computer can share thee programs of another, save data onto their hard disk and use printed connected to them. Each computer acts as both a client and a server and can communicate directly with all of the others. Security is distributed and the users of each computer have to be able to grant access rights to its resources and allot passwords. As data is stored on all f

Answer 380

In a peer-to-peer network, the computers are simply connected together without any one computer having superiority over the others. All of the computers on a peer-to-peer network are equal. Through sharing rights granted by the users any computer can share thee programs of another, save data onto their hard disk and use printed connected to them. Each computer acts as both a client and a server and can communicate directly with all of the others. Security is distributed and the users of each computer have to be able to grant access rights to its resources and allot passwords. As data is stored on all of the computers and is not held centrally, all the users are responsible for backing up procedures.

Answer 381

A computer needs some hardware and also some software that allows it to communicate with the other computers.

Answer 382

Twisted pair cables

Answer 383

Cables in which pairs of copper wires are twisted together and carry electrical signals.

Answer 384

Electromagnetic waves that can be used to carry data between computers.

Answer 385

Agreed rules for requesting and sending data across networks.

Answer 386

The main printed circuit board of the computer; it has connectors that other circuit boards can be slotted into.

Answer 387

Cables which are made of glass and transmit information encoded in beams of light. They are much faster than twisted pair cables at transmitting data.

Answer 388

Network Interface Card

Answer 389

Network adapter

Answer 390

It is a component that connects a computer to a network. It formats the data sent from the computer into a required format according to the protocols (rules) of the network.

Answer 391

The motherboard

Answer 392

Media Access Control

Answer 393

The MAC (Media Access Control) address.

Answer 394

Every MAC address is unique so that all data on a network can be sent to the correct component . MAC addresses are 48 bits in length, usually displayed as a 12-digit hexadecimal number.

Answer 395

Network switches allow individual devices to connect to a network using cables.

Answer 396

all of the computers on a network plug into a port on the switch using a cable. switches read the messages passing through them. they can read the destination addresses and send them to only the intended computers. they can do this because they build up a table of MAC addresses on the network to cut down on unnecessary network traffic. switches can send and receive information at the same time.

Answer 397

The overall network usage caused by all of the data that is being transmitted at a given time.

Answer 398

To connect to a network.

Answer 399

To allow messages to be transmitted between computers in a single network.

Answer 400

To transmit messages between computers on different networks.

Answer 401

cables radio waves

Answer 402

Routers and switches both read the address information and forward the messages to the correct network. A switch does this within a single network, but a router does this across several networks.

Answer 403

Routers are commonly used in the home to allow many computers to access one internet connection. The router links the home network to the Internet. The router will transmit the incoming web pages, streamed audio, etc. to the correct computer on the network.

Answer 404

Wireless Access Point

Answer 405

Wireless access points allow wireless devices to connect to a wired network.

Answer 406

Wireless access points convert data they receive through cables into a wireless signal (and vice versa) to allow wireless devices to connect to a wired network.

Answer 407

False. Unlike switches, they CANNOT direct messages to particular devices.

Answer 408

A computer that can serve world wide web pages to other computers that request them.

Answer 409

A set of technical standards for connecting computers.

Answer 410

The number of waves per second.

Answer 411

A set of technical standards or protocols for short-range connection of digital devices using radio waves.

Answer 412

A set of technical standards or protocols for short-range connection of digital devices using radio waves.

Answer 413

Bandwidth is the amount of data that can pass through a transmission medium per second.

Answer 414

Bits per second (bps) or megabits per second (Mbps) - bandwidth is a measure of how many bits can get through a particular point in a second.

Answer 415

Copper wires carry the data as electric currents.

Answer 416

Fibre optic cables transmit data as pulses of light generated by a LED or laser.

Answer 417

Light Emitting Diode

Answer 418

Far greater bandwidth Can carry signals much faster Can travel over greater distances without needing to be boosted

Answer 419

Electromagnetic radiation travelling in waves with a frequency higher than 1 GHz.

Answer 420

Radio waves are used to transmit data across networks in frequencies of between 2.4 and 5 GHz.

Answer 421

The Internet is a global system of interconnected computer networks which serves billions of users worldwide - this makes it a wide area network.

Answer 422

Email World Wide Web (www)

Answer 423

British scientist, Tim Berners-Lee

Answer 424

Time Berners-Lee launched the first website in 1990.

Answer 425

A host is a computer which can be accessed by users working at remote locations using networks, including the internet.

Answer 426

Web hosting companies rent space on their servers where people can develop their own websites that can be accessed by users all over the world using the World Wide Web.

Answer 427

4 - today there are 10s of millions.

Answer 428

It was established to oversee the policies and protocols that define how we use and interact with the Internet.

Answer 429

A DNS (Domain Name Server) is used to translate the URL to an IP Address. It does this by sending the domain name to the DNS, then, the DNS finds the corresponding IP Address of the domain name sent. This IP address is sent back to the browser. Finally, the browser uses the IP address to access the web page.

Answer 430

HTTP is a set of rules that is used to send data across the internet.

Answer 431

This is a protocol that ensures a secure connection is made between the devices before engaging in the transfer of data. The data packets are encrypted before they are sent across the internet and decrypted once they reach their destination. HTTPS uses SSL and TLS

Answer 432

The web server sends a copy of its SSL certificate to the web browser The web browser confirms the legitimacy of the certificate If legit, the web browser sends a signal back to let the web server know Connection begins

Answer 433

1) never save passwords for quick access 2) never give out credientials 3) use a strong password 4) frequently change password

Answer 434

1) Read 2) Write 3) Execute 4) None

Answer 435

Can access files or directories, user can only read and not make any changes

Answer 436

Ability to also modify the file

Answer 437

Ability to execute a file. (executable programs need this permission to allow the OS to run them)

Answer 438

Total access for all users

Answer 439

Domain names

Answer 440

Internet Protocol addresses (IP)

Answer 441

Translates domain names to IP addresses so browers can load internet resources

Answer 442

A unique IP address

Answer 443

three! (bus, star and ring)

Answer 444

A terminator at the end of a cable

Answer 445

Each device is connected in a ring so each is connected to two other devices

Answer 446

Each data packet on the network travels in one direction. Each device receives each packet in turn until the destination receives it.

Answer 447

Each device on the network has its own cable which directly connects to a swtich or hub.

Answer 448

Star network

Answer 449

a wireless NIC

Answer 450

A wireless router is connected to a physical network (ethernet) and uses radio signals

Answer 451

Converts data into a radio signal and also decodes it so that the computer can understand it

Answer 452

It examines the traffic coming in and out of the network And ensures the traffic meets a certain criteria If traffic does not meet the criteria, it will block the traffic and warns the user of a possible security issue Firewall also can add undesirable IP addresses onto a blacklist so it cannot be accessed

Answer 453

A proxy acts as an intermediary between the user’s computer and a web server so it prevents direct access to the webserver. It filters traffic and will block requests to certain websites if needed. It can prevent hacking and DDOS of the web server.

Answer 454

Hypertext Markup Language, a standardized system for tagging text files to achieve font, colour, graphic, and hyperlink effects on World Wide Web pages.

Answer 455

It was first developed by Tim Berners-Lee in 1990

Answer 456

It needs to contain and

Answer 457

Image, heading, table, link

Answer 458

Anchor - used in to make a hyperlink

Answer 459

needs to have a link associated with it

Answer 460

It allows authors to arrange data – text, preformatted text, images, links, forms, form fields, other tables, etc. – into rows and columns of cells.

Answer 461

Using width='' ” and height='' ”

Answer 462

Eg. img src=”example.png” width=”400” height=”400” class=”onetwothree”

Answer 463

Cascading Style Sheets is a style sheet language used for describing the presentation of a document written in a markup language like HTML.

Answer 464

In the same folder as the .html file, put the style.css file, and in the .html file, say:

Answer 465

In style.css, .example{ background-color: rgb(200,300,200); }

Answer 466

Put “.” + “name of class”

Answer 467

.img{ //something }

Answer 468

.special{ //something }

Answer 469

p::special{ //something }

Answer 470

b::special::hover{ //something }

Answer 471

Use margin:auto