Topics in ICT
Introduction to routers in networking Wired router and wireless router explained What are core routers in networking? Virtual routers explained with its configuration Edge router explained with its types Domain Name System explained Types of computer network Functions of a router Computer scheme of work, SS1, First Term Computer scheme of work, SS1, Second Term Computer scheme of work, SS1, Third Term Introduction to computer networks Types of DNS server Open Systems Interconnect: Layers of the OSI Model Internet of Things (IoT), How IoT works, its advantages and challenges How to consume less data on android phone Best programming languages to learn The internet and world wide web explained Computer Hardware, Parts and Functions of Computer HardwareAcademic Questions in ICT
DNS belongs to layer _____ of the Open System Interconnect (OSI) model of networking.
A. One
B. Two
C. Three
D. Four
E. Five
F. Six
G. Seven
Which of the following DNS servers receive queries directly from computers, phones and other client devices?
A. Root Nameserver
B. Top Level Domain (TLD) Nameserver
C. Bottom Level Domain (BLD) Nameserver
D. Authoritative Nameserver
E. Direct Nameserver
F. Recursive DNS Server
The uppermost layer of the Open System Interconnect (OSI) model of networking is the _____ layer.
A. Physical
B. Application
C. Network
D. Transport
E. Data Link
F. Presentation
Concerning the internet of things, which of the following statement is incorrect?
A. Humans will become connected to the internet through the internet of things
B. It refers to the billions of physical devices that will be connected to the internet
C. Big data is associated with the internet of things
D. Presently, we have more humans living on earth that things connected to the internet
E. China, North America and Europe accounts for over two thirds of internet connected things
F. The ultimate goal of the Internet of things will be made a reality through IPv6
What is the first step towards disabling automatic image download on WhatsApp?
A. Click on the three dots on the top right hand corner
B. Click on the WhatsApp logo
C. Click on the settings icon on the top right corner
D. Click on the settings icon located on the to top-center of the app
E. Click directly on the storage and data icon located on the top right corner
F. Click on the mobile data usage icon located on the top right corner
The followings are ways to conserve data on android phones except _____.
A. Turning on data saving mode
B. Activating background apps
C. Use of Wi-Fi to update apps
D. Disable automatic image download on WhatsApp
E. Watch low resolution videos on youtube
F. Utilizing a reputable data saving app on google playstore
Twitter was launched in _____.
A. 2003
B. 2004
C. 2005
D. 2006
E. 2007
F. 2008
Due to the limitation of the Internet Protocol version 4 address, _____ was created.
A. IPv5
B. IPv6
C. IPv7
D. IPv8
E. IPv9
F. IPv10
One of the ways to classify computer networks will be on the basis of geographical size.
A computer network can be so small that it will require only two computers in which one acts as the client and the other as server. An instance of this small network is one created through bluetooth on two phones.
Conversely, a computer network can be so large that it spans the entire globe. This type of network will comprise billions of connected computers that interact with one another. For instance, you are reading this article which had been sent from a computer (server) which may have its location somewhere in another continent. Meanwhile, understand that you are connected to this server through a network from your service provider. As a matter of fact, this is what the internet entails.
Please read an introduction to computer networks here.
Think of the internet as the largest computer network that spans the entire globe. People fondly refer to the internet as the Network of networks. Also, understand that the internet is a public network since anyone can freely have access to it.
Below are types of computer networks based on geographical size:
Personal Area Network is a network consisting of few computers interacting with one another; and are typically within a range of 10 meters.
As the name implies , PAN is created for our personal use which could be in our homes or offices. For instance, your home may comprise of a Personal Area Network where your laptops, phones, console games like Play Station / X Box, television and refrigerator are all connected.
You can read on the internet of things here.
Personal Area Network is a small network with a maximum range of about 30 meters. Understand that networks created by Bluetooth, WiFi, infrared, xender and other similar applications are all PANs.
It is noteworthy to state that the term SOHO stands for Small Office Home Office. SOHO networks are often connected via a PAN.
Note: Personal Area Network can be created via a wireless or a wired media. For this reason, PAN is of two types. These are:
Thomas Zimmermam was the first research scientist to propose the idea of a Personal Area Network
A Local Area Network is a network formed by connection of computers and intermediary devices within a building and under a single administrative control. Intermediary devices in this instance refers to routers and switches.
Take for instance, banks and corporate buildings will usually have a LAN which must be controlled and protected by the Information Technology (IT) department present within the organizations. This will also mean that each branch of a bank will have its respective LAN managed by the IT department within such branch. This is shown in the image below:
In another instance, if we have a building which has four different companies within it; with each company having its separate network (that is, computers and intermediary devices connected appropriately), then each company within the building will be considered to have its respective LAN. In summary, we can therefore state that the specific building has four Local Area Networks within it.
A Local Area Network is dedicated to a building with its own administrative control. This is true if the building comprise of one organization only.
However, if different organizations (with their respective network administrative control) are present within the building, then, the number of LANs will be equivalent to the number of organizations within that building.
Always understand that the LAN remains local to an organization (or each organizations) within a building. Also, network security and speed are paramount within a LAN.
Cables, routers and switches are used to create the LAN network. The cables utilized can be copper twisted pair cable or coaxial cable. It is noteworthy to state that fibre optic cables aren't typically used in creating LANs, rather they are utilized in Wide Area Networks (WAN).
Please read on routers, types and functions here.
As the name implies, a Campus Area Network will typically span over a campus, an educational institution or a large college system.
A CAN connects the different departments within the campus. Also, students may also be connected to the CAN through a secure channel.
CAN is often considered as a network of multiple interconnected LAN. This implies that several interconnected LANs within a campus will give rise to a CAN. This is quite different from a Metropolitan Area Network whose interconnected LANs are within a metropolis or city.
The Campus Area Network is always bigger than a Local Area Network but smaller than a Metropolitan Area Network
You can read on application layer of the OSI model here.
A Metropolitan Area Network covers a large geographical area, usually a metropolis or even an entire city. It comprises of Local Area Networks (LANs) within a metropolis or city.
An instance of a MAN is seen when a bank has numerous branches in a metropolis or city, with all branches connecting to the headquarter (HQ) present within the same city. In this instance, the network connecting the branches to its headquarters within that metropolis (or city) is termed a Metropolitan Area Network.
Also, the military forces within a state can also make use of MAN for their network communications.
Please read on some top programming languages to learn here.
A Wide Area Network is much larger than all the aforementioned types of network. The internet itself is classified as a WAN.
The WAN spans over a large area and even the entire globe through some advance technologies that utilizes high speed routers and switches, cellular networks, satellite links and fibre optic cables that can run between continents.
You can think of a WAN as a network that connects all public networks on the internet. In this regard, you are able to access Google's network, Facebook's network, Amazon's network and other public networks on the internet through the WAN.
Please read on the internet and world wide web here.
Your service provider will often charge you for data which will be used to access the WAN. The WAN enables you access information from other computers (called servers) scattered around the world.
Examples of Wide Area Network includes :
Note: Apart from the geographical classification of network, computer networks can also be classified based on its design.
The two main form of networks based on designs are:
Client / Server Network
Peer to Peer Network
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Amazing facts in ICT
1,000 computers are used to retrieve the answers to your Google search (query) in 0.2 seconds
The first hand-held mobile phone call was made in New York City on April 3rd, 1973
The logo for gmail was designed the night before it was launched
Coca Cola owns all the domain names (website names) that can be read as ahh. They include: ahh.com, ahhh.com, ahhhh.com, ahhhhh.com, ahhhhhh.com and so on..., all the way up to 62 'h's!
YouTube is a video-sharing platform which commenced operations on February 14, 2005 (Valentine's day). Three former PayPal employees -> Chad Hurley, Steve Chen and Jawed Karim created the YouTube service (as a dating app) until Google bought it in November 2006 for US$1.65 billion
Smoking near an Apple (Mac) computer voids the warranty.
When you add /4 to the end of Facebook's URL, it will take you to Mark Zuckerberg.
You can try it on you own; or better still, try the link below:
Apple iPad retina display is actually manufactured by Samsung
The big five tech companies of the world as at 2018 are :
Apple
Amazon
Microsoft
Notable points in ICT
Python is one of the most popular programming languages, and will still remain relevant for a long time.
Python can be used for almost every kind of project including web application, machine learning, mobile and desktop applications, networking servers, APIs, scrapers, application’s backend and so on.
There is a great availability of third-party libraries for the python language. For this reason, it becomes one one of the easiest languages to learn as a beginner.
Believe it or not, Hypertext Preprocessor (PHP) still remains one of the most popular backend language for web applications, even though it is currently facing a stiff competition from python language.
Content Management Systems (CMS) like wordpress and drupal are written in PHP for its backend. Interestingly, some of facebook’s backend were also written in PHP.
As at 2019, the backend of more than 40% of active websites are powered with PHP. In fact, Len Academy is also powered by PHP for its backend.
If you wish to manipulate databases via Structured Query Language (SQL) with a programming language that has dynamic capabilities, then PHP is your language of choice.
Below are notable dates on internet evolution:
1983: The Domain Name System (DNS) created the '.com .edu .gov .org and .net' systems for naming websites
1985: The first registered domain name - 'symbolics.com' came into existence
1992: The first audio and video were uploaded over the internet
1992: The phrase 'surfing the Internet' became popular
1993: The number of websites reached 600
1993: White House and United Nations go online
1994: Microsoft creates a Web browser for Windows 95
1994: Yahoo! is created by Jerry Yang and David Filo
1995 Amazon and eBay were launched online
1996: 'The Dancing Baby' becomes the first viral internet video
1997: Netflix is founded by Reed Hastings and Marc Randolph
1998: Google search engine came into existence
2003: The worm 'SQL Slammer' spread over the internet within 10 minutes
2004: Facebook goes online
Computer hardware is the collection of physical parts of a computer system.
Physical parts of a computer are those parts that you can see and touch. It may also be referred to as the 'equipment of the computer'.
When the computer case is opened (with a screwdriver), one would see the different hardware components inside of it. It's important to state that some other hardware components are present outside the computer case; and these are termed peripherals.
Below are hardware components seen inside the computer case:
Motherboard
Central Processing Unit (CPU)
Graphics Processing Unit (GPU)
Power supply Unit (PSU)
Northbridge
Southbridge
Peripheral Component Interconnect (PCI) slots
Network Interface Card (NIC)
Random Access Memory (RAM)
Ventilation fans
Heat sink
Solid State Drive (SSD)
CMOS battery
Optical Disc Drives (external present)
USB port, PS2 port, Ethernet port and other ports
Expansion Ports / Slots
Hardware components seen outside the computer case are called peripherals. The peripherals are grouped into the following:
Input devices: They provide information to the computer.
Output devices: Brings out information from the computer.
Storage devices: They store information or data.
Below are examples of some peripherals:
Keyboard (input)
Monitor (output)
Mouse (input)
Webcam (input)
Touch Pad (input)
Universal Serial Bus (USB) flash drive or memory card (storage)
Hard disc drive (storage)
Stylus (input)
Joystick(input)
Printer (output)
Speaker (output)
Headphones (output)