Digital Society 3.4 - Networks and The Internet

Personal area network (PAN) Local area network (LAN) Metropolitan area network (MAN) Wide area network (WAN)

• smallest type of network

• consists of connected devices in close proximity to an individual

• typical PAN: wirelessly connecting a phone and printer to a laptop, health watch wirelessly syncing data to phone

• a group of computers or devices connected on a single site

• small scale: a home with two/three users

• large scale: office/school that may have hundreds of users

• usually set up to help sharing of resources eg: give access to a centralized store of data in an office/sharing printer at home/sharing internet access in school

• network that covers a larger geographical area

• connecting two or more computers that are not in the same building or campus but in the same city

• covered area between 5 to 50km eg: governments provide free wi-fi access to residents/municipalities that connect traffic lights or parking meters to a single network

• future use: toad infrastructure used by autonomous vehicles

• largest of network spread across a wider geographical area

• can be a collection of LAN connected by telco technologies

• can be an organization that operates nationally or internationally

• a company can have many different offices in different cities connected by public telco network in order to share centrally held resources and application

• this eliminates the need of servers at each location, all offices can access the same data

• the largest WAN accessible to public is the internet (a collection of networks and networking technologies that link billions of users worldwide

• use virtual private network (VPN)

• the organisation may lease a dedicated line from their ISP, which they do not have to share with any other organization in the area

• wired networks

• wireless networks

• cloud networks

• device connected to copper ethernet cables using an ethernet port and a router or switch

• ethernet port could be: integrated onto motherboard/installed as separated NIC

• crossover: between same devices straight through: between different devices (Switch to router)

• fibre optic: better connectivity over greater distance, faster speed BUT higher cost, sensitive because complexity

• coaxial: as backbone

• more reliable

• operate at faster speeds

• able to transfer data more securely (used by businesses and governments)

• use of wireless technologies to connect the different nodes to form a network

• wi-fi: embedded wireless NIC connecting by a wireless access point (WAP) or wireless route

• uses cables to connect to a wired backbone

• uses radio signals to send data

• easy to set up

• offers flexibility because can connect anywhere within range

• incorporate some or all the network capabilities on a public or private cloud platform

• not same as cloud storage: pay to store data at provider

• companies can install access points on sites but management of network or data can be hosted off-site (with connection of internet)

• easier to deploy

• easier to relocate or hire more people

• saves costs

• allows scalability because configuration to network can be made by accessing the IP address of hardware controlling the wireless network

• server: can be hosted internally by the organization or externally in the cloud

• clients: devices such as personal computer or mobile devices

• advantage: organizations can prioritize IT resources that will secure the data

• disadvantage: must be adequate bandwidth for all clients to request access at the same time

• file transfer protocol clients (FTPs)

• domain name system (DNS) server

• online banking service: Bank Islam

• social networking sites

• a decentralized network

• in which each computer is equally responsible

• for storing and sharing data

• illegal sharing of copyright content like movies and music

• difficult for authorities to shut illicit activities down

• online gaming platforms: Blizzard Entertainment, Wargaming

• cryptocurrency network model

• BitTorrent: largest P2P communication protocol for distributing data and large files over internet

• overall: to speed up large downloads for both individuals and organizations

• more stable than P2P

• used in both small and large networks

• network administrator can backup data

• more secured because data protected due to centralized with the central management

• more expensive to configure and set up server

• centralized: requires administration for central

• requires expertise to set up

• network traffic congestion: system overload cause danger to system, cannot access info

• affordable because no need for expensive server

• no complex administration (user can set own permission to file they're willing to share)

• easier to set up

• network is not dependent on one server

• less stable

• data cannot be centrally backed up

• security and privacy issues (network can be compromised because remote users can access without proper permission)

• vulnerable to virus attacks (easily spread even protected by antivirus or firewall software)

• client and servers are distinguished in C/S while in P2P they aren't

• C/S concentrates on sharing the information and service for data while P2P concentrates on connectivity and communication

• C/S used in small and large networks while P2P mostly used for short networks

• in C/S, server respond the service which is request by client while in P2P, each node can do both request and respond for services

• device for converting data into a digital signal

• and communicating this data to a network

• a unique identifier

• assigned to every piece of hardware

• at time of its production

• MAC is constant, IP will change according to router

• MAC: made up of 48 bits of data in hexadecimal characters

• a networking technology

• that translates data from one network to another

• by the most efficient route possible

• assigns IP addresses to devices

• allows us to connect internet from home because forwards data packet to modem and then ISP

• a device that convert digital data to analogue data

• so it can be transmitted over a telephone line

• many ISPs offer faster connection using fibre optics router and modem

• a device that creates a wireless LAN

• to improve coverage throughout a building

• strategically placed around building

• has a no. of dedicated radio channels computers can connect to

• networked with a cable connected to either a switch or hub (shows that even a wireless network still has some wired components)

• the least intelligent of the devices

• that broadcast data to all devices on the network

• uses a lot of bandwidth and uses unnecessary data

• easier to set up and useful when connecting only a few devices eg: game consoles of a local multiplayer game

• more powerful and intelligent device

• that will forward the data packets more efficiently

• give the network manager more control over how data is shared across network

• allows different digital tech or systems

• to connect and exchange data with one another without restrictions

• a set of agreed rules

• that state how to format, send and receive data

• both sides must accept and follow the protocols to successfully transmit data

• layers of network protocol makes it easier for standards to be put in place

• protocol that defies where data is to be sent to and from (IP)

• and how data is to be broken down into packets before sending (TCP)

• a logical numeric address that is assigned to every node on a network

• every time a device connects to a network, an IP address will be assigned to it by dynamic host configuration protocol (DHCP)

• web servers usually have a fixed IP address

• a server that translates domain names into IP addresses how it works:

• by looking up IP address in database of public IPs

• sends the data packets from user to the address

• application layer

• transport layer

• internet layer

• physical network layer

• set of protocols used by applications eg: web browser

• sets up the communication between hosts using protocols such as UDP and TCP

• TCP: data is exchanged by providing end-to-end communication

• instructions included alongside the data on how to reassemble it back to its original form

adds the sender and recipients' IP address and routes the packets across a network

allows different networking technologies to work together eg: Ethernet

• a process that reduces size of a file

• by re-encoding it to use fewer bits of storage than the original file purpose:

• to make storing and streaming of data more efficient

• to reduce amount of space needed to represent a file

• lossy compression: JPG, MP4 - reduces file size by permanently removing unimportant data from file

• lossless compression: PNG, ZIP, BMP - reduces file size without losing data (data can be returned back to original size after transmission, have to unzip using same application (zip))

• the concept that all data requests on the internet should be treated equally by the ISPs

• about equal bandwidth, not content

• advantage to users and smaller companies to innovate with same level as others

• gives advantage to ISPs to provide plans and get more money

• money is used to increase quality of network by improving infrastructure of network eg: Netflix buy bigger plans so ISPs can use more money to invest

• the use of multiple method of authentication to verify a user's identity

• can be physical (use of token, card, text message) or something part of user

• controlling access from inside threats

• set uo/configure network access controls to control how users access physical resources and data

• users use a unique username, strong password for authentication

• network administrator determine which files and resources will be accessible and what type of access will be given (read-only or full control)

hardware or software designed to block unauthorised access to a network by inspecting incoming and outgoing network traffic

• controlling access from outside threats

• firewall software: part of OS , firewall hardware: used by large organizations

• block unauthorized access to network by inspecting packets trying to enter or leave the network

• requests are rejected or accepted depending on set of rules defined by the firewall

• computer system that acts as an intermediate

• between client or network and the internet providing an additional layer of security

• installed at network's gateway, to accept or forward connection requests

• uses anonymous network ID instead of the actual IP address of the network address

• filters content requests from within network

• limit users from accessing certain undesirable/unproductive sites

• by using keywords or blacklisting web addresses

encryption: to help secure data on networks by encrypting data on the server storage device/encrypting wireless connection using WPA (wi-fi protected access)

• as mobile carrier/mobile phone operator:

• MSP purchase a license to transmit radio signals over a specific range within a particular frequency band

• used to provide high data speeds

• for service (phone calls, send and receive texts, use data to browse webs)

• regular: user call a landline/another mobile phone, audio data transferred wirelessly from a cell tower to a cell tower

• VoIP: audio data transferred into digital packets sent via internet between two devices eg: Skype, WhatsApp, Facebook Messenger

• online services such as browsing web, online shopping, file sharing, video conferencing

• email, domain registrations, web hosting

• the global collection of networks and networking technologies

• that link billions of users worldwide

• the websites and web services that are hosted on web servers, identified by their URL (uniform resource locator)

• main technologies to allow for interoperability between all technologies on the internet are URL, HTTP, HTML

• HTTP: hypertext transfer protocol

• HTTPS: secure hypertext transfer protocol

• determines how web resources are transmitted between the web browser and the web server

• HTTPS: a requirement of many web browsers --> force web-hosting companies to add security certifications (encryption) to their servers

• the unique address of each resource on the web

• could be the address of a web page or the file hosted by a web server

• the format of web pages that allows documents to be displayed as web pages

• as well as to link them together

• first computer network in 1965: University of California, LA to send message to a computer at Stanford University

• first attempt: caused a system crash

• second attempt: led to creation of ARPANET (Advanced Research Projects Agency Network) in 1969

• ARPANET expanded to include 30 academic, military, research institutions from different locations

• introduced TCP/IP protocol until 1990

1989: for the info being shared to be structured and linked in a new way that made it quicker and easier to access 1993: only 130 websites 1996: grew to 100,000 websites

• formed in 1994 to promote its evolution and ensure interoperability

• to coordinate development of both web technology and standards

• uses process that promote development of these standard: based on the agreement of a wide range members (working for organizations all over the world)

web 1.0:

• websites considered static, did not change frequently

• every change of content/formatting required a programmer

web 2.0:

• new tech and protocols developed

• enabled users to generate own content with being coding experts

• web developers use XML and RSS to format and structure websites

• allowed more dynamic content: separated from formatting

• introduce social media platforms, blogging, social bookmark, podcast

• innovate users experience, more intelligent

• generate a greater understanding of the meaning of the words being used when creating, sharing, searching content

• to utilize AI and natural language processing

• can display interactive 3D graphics

• can grow the market of IoT

• internet-collected devices that collect and share data

• uses sensors to collect data, communicate with other over a network

• to provide assistance or increase efficiency eg: appliance, autonomous vehicles, phones, items, smart home tech (eg: smart lightbulbs controlled with a phone, smart door locks let delivery drivers drop off packages)

• cost: fair competition for all companies because pay the same rate for same speed

• content and access: freedom of expression and free speech, citizens can be exposed to cultivate open-mindedness

• innovation: more innovation, creative and knowledgeable, resourceful because can share unlimited content to innovate

• domination: prevent domination from big companies, government provide infrastructure while companies only operate eg: Celcom and Maxis own telecom infrastructure

• cost: companies with lower use of internet speed have to pay same rate as big companies

• content and access: offensive, dangerous and illegal content is accessible to everyone and difficult to remove, removing net neutrality makes it easier for ISPs to filter dangerous content eg: black market, dark web

• domination: low service because companies does not maintain and control infrastructure

- spamming

- hacking

- viruses

- ransomware

- phishing

- DDOS

- spamming: the sending of unsolicited emails for the purpose of advertising

- solution: email filtering, spam emails filtered before reaching inbox

- 45% email traffic was spam

- hacking: unauthorised access to a computer or network that can be accomplished many ways which are:

- social engineering: manipulate a user into sharing username and password with a fraudster to gain instant access (eg: impersonate staff)

- hacking website/penetrating network: gaining access to back-end database of user info/redirecting user to different website

- exploiting a security flaw: used if network has no malware/virus protection / firewall, can gain access to company servers

- ransomware: a malware that infects a computer

- effectively locks user out of own device

- demands payment to unlock it

- typically activated by: clicking an email attachment, hidden in a software download, visiting a malicious website or link

- phishing: a type of social engineering

- involves sending fraudulent emails

- to trick users revealing sensitive information

- when a network of computers has been installed with malware designed to target a web server

- when hacker wishes to attack

- instruct army of infected computers (bots) to make a connection to target web server at same time

- web server cannot cope with spike in demand, prevent other users from accessing website

- anonymity: use of digital tech to conceal a person's true identity

- can make way for internet trolls, identity theft, loss of rights to be forgotten

- internet trolls: people who leave provocative/offensive message online

- to get attention, cause trouble or upset someone

- people that target influencers with a large social media or people that just enjoy causing harm to others

- causes significant harm and stress (disrupted sleep, low self-esteem, self harm)

- personal data no longer needed by organization

- individual withdrawn

- no longer a legitimate reason to keep data/data obtained unlawfully

- individual object data used for direct marketing purpose

- the close monitoring of a person or a group of people

- combined with facial recognition and AI technologies

- government monitoring of communications: for national security, causes privacy concerns which is monitor if ordinary citizens

- drones: to capture aerial video footage, can be controlled remotely, an effective way to monitor area

- wearable cameras: cameras capturing without knowledge or consent (eg: policeman body camera, skateboarder's GoPro)

- location services: to improve performance and allow users access to full features of app, collects irl location

- smart home tech: monitor environment to perform function efficiently

- trace and track apps: (covid-19) to be able to visit places outside of their home