Social Issues and Professional Practices

Computer Networks, Internet and Social Media

Computer Networks

is a system of intrerconnected computers and devices that communicate with each other to share resources such as files, applications, and internet access.

Computer Networks

these devices are connected via wired (like Ethernet) or wireless (like wifi) communication channels

Access Point Device

Hub

Access Point Device

router

Access Point Device

switch

Access Point Device

modem

Access Point Device

bridge

Access Point Device

brouter

active hub

role: is a type of network hub that amplifies and retransmits data signals

active hub

function: it works at the physical layer (layer 1) and is capable of boosting the signal strength of incoming data so it can travel further. it also splits the network traffic to multiple connected devices

active hub

example: used in small networks where the distance between devices is too large for direct communication

passive hub

role: is a basic type if hub that does not amplify or process signals; it simply directs traffic to all devices connected to it

passive hub

function: it operates at the physical layer (layer 1) and acts as a central connection point, but does not alter or manage the data in any way. essentially, it just passes along the signal without any notification.

passive hub

example: used in older or simpler network setups, though less common today due to their inefficiency

router

role: connects different networks, such as connecting your local home network (LAN) to the internet (WAN)

router

function: it directs data packets between devices in different networks by analyzing their IP addresses and determining the best path for transmission.

router

function: helps in managing traffic between internal and external networks and can provide firewall features for security

router

example: home routers which route traffic between your home wifi network and your internet service provider

switch

role: is used to connect multiple devices within the same network (e.g. in a LAN)

switch

function: operate at the data link layer (layer 2) and uses MAC addresses to forward data to the correct destination.

switch

function: unlike hubs, which send data to all connected devices, a ___ sends data only to the device it’s intended for, making it more efficient.

switch

example: a __ in an office that connect multiple computers to allow them to communicate with each other and share resources

modem (modulator-demodulator)

role: is used to convert digital data from a computer into analog signals for transmission over telephone lines or cable and vice versa

modem (modulator-demodulator)

function: it modulates and demodulates signals so that data can travel over communication mediums (like phone lines or cable TV lines).

modem (modulator-demodulator)

function: it enables internet connectivity for homes and businesses

modem (modulator-demodulator)

example: dial-up modems (older technology) or broadband modems used in modern cable internet connections

bridge

role: connects two or more network segments, creating a larger network and reducing collisions

bridge

function: it operates at the data link layer (layer 2) and filters traffic based on MAC addresses, forwarding data only when necessary.

bridge

function: it can help divide traffic between segments to reduce congestion

bridge

example: connecting two wired networks in a large building so that data can flow between them

brouter (bridge + router)

role: is a combination of a bridge and a router, providing the functionality of both

brouter (bridge + router)

function: it operates at both the data link layer (layer 2) and network layer (layer 3). it can forward data like a router, but it can also bridge networks like a bridge.

brouter (bridge + router)

function: it is used for routing traffic between different networks and filtering data traffic toi reduce congestion, much like a bridge

brouter (bridge + router)

example: used in complex networks that require both routing and bridging capabilities, such as large enterprises or data centers

PAN (Personal Area Network)

is a small network, typically for personal devices that connects devices such as smartphones, laptops, tablets, and Bluetooth devices within a very short range (usually a few meters).

PAN (Personal Area Network)

It allows users to easily share files, connect peripherals like printers, or sync devices. common examples include bluetooth connections between a phone and a wireless speaker or a laptop and a wireless mouse

HAN (Home Area Network)

is a network specifically designed to connect the various devices in a home. This includes smart devices like smartphones, tablets, computers, smart TVs, printer, and IoT (internet of things) devices like smart thermostats and security cameras.

HAN (Home Area Network)

the goal of a ___ is to provide seamless communication between devices in a household, often managed via a wifi router. examples include controlling lights and appliances through a smartphone app

LAN (Local Area Network)

connects devices within a small, localized area like a home, office, or school. it allows devices such as computers, printers, and servers to communicate and share resources like files and printers.

LAN (Local Area Network)

__ are typically fast and cost-effective, using wired (Ethernet) or wireless (wifi) connections. an example would be a network in an office or classroom

CAN (Campus Area Network)

is a network that covers a medium-sized, such as a university campus or business complex. il links multiple buildings on the same site and is typically larger than a LAN but smaller than a MAN

CAN (Campus Area Network)

__ can provide communication, internet access, and resource sharing across different departments or oreas within the campus

MAN (Metropolitan Area Network)

spans a larger area than a LAN but smaller than a WAN, typically covering a city or a metropolitan region.

MAN (Metropolitan Area Network)

it connects various buildings or offices in a city of campus, and it may also provide internet access and other services within a metropolitan

WAN (Wide Area Network)

covers a large geographical area, such as cities, countries, or even continents.

WAN (Wide Area Network)

the internet is the most well known WAN, connecting millions of LANs worldwide.

WAN (Wide Area Network)

are used by businesses with multiple locations to link their offices or by telecom providers to offer internet services to consumers

SAN (Storage Area Network)

is a specialized network designed to provide high-speed access to storage devices such as disk arrays, tape libraries, and optical jukeboxes.

SAN (Storage Area Network)

Unlike a regular network, a __ operates independently of the standard network infrastructure and is used by organizations to consolidate storage resources and improve access speed for data storage and backup solutions.

SAN (Storage Area Network)

it provides a dedicated pathway for storage traffic, ensuring high performance and scalability for large-scale data operations

VPN (Virtual Private Network)

allows secure communication between devices over a public network (like the internet) by creating a private, encrypted tunnel.

VPN (Virtual Private Network)

are often used by remote workers to securely connect to a company’s internal network or to protect privacy when using public wifi

Digital Divide

typically exists between those in cities and those in rural areas; between the educated and the uneducated; between socioeconomic groups; and, globally, between the more and less industrially developed nations.

Digital Divide

even among populations with some access to technology, the digital divide can be evident in the form of lower-performance computers, lower-speed wireless connections. lower-priced connections such as dial-up and limited access to subscription-based content

Digital Divide

initially attributed to underdevelopment and was perceived as something temporary that would disappear with the popularisation of technology. instead, the divide persists today despite the mass marketing of electronic devices with internet access. the causes can range form the high price of the above-mentioned devices to the lack of knowledge about their use or the lack of infrastructure for their access.

Access Divide

refers to the possibilities that people have to access this resource. this is where socio-economic differences between people and between countries come into play, since digitisation requires very costly investments and infrastructure for less developed regions and for rural areas

Use Divide

it refers to the lack of digital skills, which impedes the handling of technology. in this regard, and to give an example, the ITU points out that there are 40 countries in which more than half of their inhabitants do not know how to attach a file to an email

Quality of use gap

sometimes theu have the digital skills to find their way around the internet, but not the knowledge to make good use of and get the most out of it. for example, with regard to access to quality information

consequences of digital divide

technological discrimination is a form of poverty and social exclusion, depriving some citizens of essential resources for development and wealth generation. we have seen this a lot during the COVID-19 pandemic, as many students found it difficult to work from and follow classes online

consequences of digital divide

lack of communicaiton and isolation

lack of communicaiton and isolation

people in remote areas who do not have access to the internet are disconnected. something similar happens to urban residents who are disconnected which causes social isolation

consequences of digital divide

barrier to studies and knowledge

barrier to studies and knowledge

the coronavirus crisis has shown the effects of the digital divide in education: teachers and students out of the loop because they lack sufficient technology and digital skills. It also increases lack of knowledge by limiting access to knowledge

consequences of digital divide

accentuates social differences

accentuates social differences

digital illiteracy reduces the chances of finding a job and accessing quality employment, which has a negative impact on the workers’ economy

consequences of digital divide

gender discrimination

gender discrimination

as we saw at the beginning, the digital divide negatively affects women more than men, which violates the principles of gender equality

internet growth

the internet has grown rapidly within the past decade

internet growth

it has changed the way the world communicates through the media

internet growth

internet access has globalized the world

affect on newspapers

newspaper businesses have decreased in size and numbers

affect on newspapers

the internet has also affected newspapers worldwide, such as in australia and the United Kingdom

affect on newspapers

traditionalists believe that the newspapers can adjust to change within new environments, while others believe that newspapers will eventually become extinct in the United Kingdom

affect on libraries

virtual library environment

affect on libraries

future directions

affect on libraries

overall, the internet’s effect on libraries has resulted in quick and easy access to information for users

virtual library environment

reached locally and globally

virtual library environment

allows resources to be digitalized and saved

future directions

libraries must organize and reorganize information effectively and accordingly

affect on children

special software that teaches elementary-aged children basic skills

special software that teaches elementary-aged children basic skills

abcs and 123s

affect on children

critical learning

critical learning

educational computer games

affect on children

technology can expand children’s knowledge of the world

Affect on teens (positive)

schoolwork

Affect on teens (positive)

educational research

Affect on teens (negative)

addiction

Affect on teens (negative)

necessity

Affect on teens (negative)

deterioration of social skills

Affect on teens (negative)

impatience

Affect on teens (negative)

replace personal needs and social interactions with the internet