Internet Infrastructure

Assalamualaikum and hello readers. Basically, this is the final post for this subject and hopefully it will somehow benefits all of you.
In this posting, it will be based on the Hierarchy of Networks, Internet Protocol (IP), Domain Name System (DNS), Internet Service Provider (ISP) and last but not least HTTP.

HIERARCHY OF NETWORKS

1. From single computer to Local Area Networks, which means to lots of other computers.

2. From Local Area Networks to Internet Service Provider (ISP) such as Maxis and TMNet

3. From ISP to World Wide Web (WWW)

INTERNET PROTOCOL (IP)

- It is an Internet standard protocol that provides a common layer over dissimilar network.

- The role IP: It is to move packet among "host" computer through gateways

- Every computer is assigned with different and unique IP address

- IP address consists of 32 bits [Shown as 4 octets of numbers from 0-225 which is represented in decimal form instead of binary. 

*Eg: DECIMAL: 168.212.226.204

BINARY: 101010000.11010100.11100010.11001100

- IP address has two parts; identifying the network and identifying the node/host


- Class of addresses determines which part belongs to the network address and which belongs to the nodes.
- All the nodes on a given network share the same network prefix. However, it must have a unique host number.


DOMAIN NAME SYSTEM (DNS)
- It is an Internet service that translates domain names like www.yahoo.com into numerical IP address like 204.62.131.129
- Domain names are alphabetic hence it is easier to remember.


INTERNET SERVICE PROVIDER (ISP)
- Directly connects client to the Internet via copper wires, wireless or even fiber optic connections.
- There are basically FOUR types of ISP which are hosting, transit, virtual and free ISPs.


HTTPS
- HTTPS stands for Hypertext Transfer Protocol Secure.
- Provides encrypted communication to prevent eavesdropping and to securely identify the web server with which you are actually communicating.
- Used for protecting page's authenticity on all types of website, securing accounts as well as keeping user's communication, identity and browsing history private.

With that, that's all from me. Hope you readers enjoyed browsing through and gain some input from what have been posted here. ^^ 

Wireless Technology: Part Two

Assalamualaikum and a very good day to all. ^^


This post is a continuation of the previous topic which is on wireless technology. So, basically, this post will touch on the topic of Bluetooth, Broadband as well as Infrared.


Bluetooth

• Bluetooth is an open wireless technology standard for exchanging data over short distances.
• Basically, it uses short wave-length radio transmission.
• It creates high-level security of PANs.
• Bluetooth provides a secure method in order to connect and exchange data and information between devices.
• Example of application:

1. Wireless control of and communication between a mobile phone and hands free headset.
2. Wireless Bluetooth headset and Intercom.

• Examples of devices:

Faxes | Mobile phones | Laptops | Digital cameras | Personal computers

Logo of Bluetooth

An example of a Bluetooth device

Broadband

• Broadband handles a wide range of frequencies.
• Provides and easier way for users to surf Internet as portable modems are provided. The users are only left to connect it to their notebooks.
• Devices normally used in the application of broadband are:

PC cards | USB modems | USB sticks 

• We could actually find different broadband from different companies such as Celcom, Maxis, Digi, Vodafone and many more. 

Broadband from the Maxis company

Jjang! Another one: Celcom broadband

Infrared

• The technology of infrared allows the communication devices to work at a short-range wireless signals. 
• Computers can transfer files easily in a two way direction.
• There's a device called an infrared adapter where it functions as data transmitter and receiver, which is installed in many handheld personal devices. 
• Supports connections between to devices only.
• It spans very short distances and two devices cannot be placed far than 5 meters from each other.

All in all, all these technologies play an important role in our daily activities. Every one needs these technologies in order to make their lives far more easier. As we know, the world is getting more advanced than it is before and many new inventions of technology is being introduced day by day. Make use of these technologies and learn how to use them with proper manner. As a student, personally, I reflect that these technologies do assist me in my everyday routine. For instance, Bluetooth and broadband. Almost every student own their very own mobile phones installed with Bluetooth application as well as a broadband which makes us easier to complete our assignments. Same goes to my self. It is undeniable that we tend to depend mostly on these inventions.


Till next time, lovely readers! ^^

Wireless a.k.a Unbounded Media

Assalamualaikum and hello to all of you readers.

First and foremost, here's the definition of wireless a.k.a unbounded media.This term means it is a media that transport electromagnetic waves without the need of physical conductors. In this case, signals are broadcasted through air or water and thus, it's available to anyone and everyone to use. However, a device is needed to actually transmit the signals.

TERRESTRIAL MICROWAVE

• Terrestrial microwave requires line of sight transmission and also reception equipment.
• The taller the antennas, the longer the sight of distance. For instance, the antennas are put at a high position such as on the hills or mountains.
• Signals from terrestrial microwave transmit signals in a one way direction, once at a time. 
• As an extra option to increase the distance, a system such as the repeater can be installed with an antenna. 

ANTENNA

For your information, there are two types of antennas namely parabolic dish and horn. 

1) Parabolic Dish

• It is based on the geometry of parabola where it works like a tunnel which catches a wide range of waves  and directing to a common point.
• This common point is called FOCUS POINT. 
• It has a line of symmetry between the two dish at both left and right hand side. 
• The devices known to use this antenna are Celcom, Maxis, and others in order to catch data. 
• The concept of this antenna is that it bounces back in one direction from one dish to another. 

The image of Parabolic Dish

2)Horn

Horn antenna from New Jersey, 1960

•  It looks like a gigantic scoop and the outgoing transmission are broadcasted up a stem and deflected outwards in a series of narrow parallel beam by the scooped shape of the horn. 

SATELLITE

• Satellite owns a similar principle as terrestrial microwave where it acts as a super tall antenna and repeater.
• Furthermore, in parallel with terrestrial microwave, satellites applies the movement of data in a single bounce method from the transmitter to the receiver. 
• Satellites have the capability of working in any location on Earth, no matter how remote it is placed. 
• It is considered very clear compared to the others as it has high quality communication without the requirement of large investments in ground. 
• This is based on its infrastructures.
• Speed = same as the Earth.
• GEOSYNCHRONOUS SATELLITE : The orbit speed is based on the distance from the planet.
• DOWNLINK : Transmission from satellite to the Earth.
• UPLINK : Transmission from the Earth to the satellites.
• Minimum of 3 satellites are required to provide full global transmission.

Here's a satellite!

RADIO FREQUENCY

• For radio frequency, the rate of oscillation is in the range of about 3 kHz to 300 GHz.
• It corresponds to the frequency of radio waves, and the alternating currents which carry radio signals.
• Antenna must be used to receive the signals.
• Usually done via a resonator which is a circuit with a capacitor and an inductor forming a tuned circuit.

• Resonator act as an amplifier to the oscillations within a particular frequency band.

CELLULAR PHONE

The examples of cellular phones these days.

The famous of all among the users ^^

• Cellular phone has a variety of transmissions. For example, 3G and 4G is implied in cellular phones as data transmitters or networks that are available.
• As for 3G, the technologies use for this network are usually WDM A, EVDO, HSP and others too.
• Other than that, it has the speed of 600Kb per second where its downlink is 1.4Mb/sec and its uplink is 5.8Mb/sec.
• In terms of data transmission, 3G networks applies the concept of circuit switching where it is done one at time.
• As for 4G, it make use of the technologies known as LTE and also WiMax.
• 4G networks has the speed which is ten times faster than 3G network where it owns a downlink of 3.6Mb/sec.
• In terms of its data transmission, 4G undergoes packet switching where it transmits data in a whole (like a bag). 

 WIFI

• WiFi is the original technology of wireless local area network or WLAN.
• It is usually based on IEEE 802.11 specifications.
• WiFi uses the same radio frequencies as Bluetooth, but with higher power consumption resulting in a stronger connection.
• The devices that are able to access this type of transmission are mobile computing devices such as laptops.
• With the frequency of 2.4 GHz, WiFi has the range 100-300 feet indoor and 300-900 feet outdoor.         

 

In a nutshell, we actually know that all of these technologies exist around us. However, to thoroughly know and gain knowledge about all these things, not everybody would have the initiative to do so. We should realize that all of these inventions has helped us in our daily lives so much, more than we could ever imagine. 

 

In terms of my lecturer's teaching, I could easily understand as she used drawings and brief explanations in order to elaborate on a particular matter. 

 

Well, enjoy reading readers! Till next time ^^

CABLING!

Assalamualaikum and hello boys and girls. It's a new topic for a new week now so let's see what I have learnt in the last lecture ^^

As you can see based on the post title, it is all about CABLING. Do you know what cabling is defined as?

Well, here's the answer!

Cabling is the medium through which the information or data is usually transmitted from one network device to another.

Moving on, there are various types of cables that we can find in the market nowadays, but for this post, you readers will be able to know about FOUR kinds of it. 

1) Unshielded Twisted Pair Cable (UTP) 

Here's a picture of UTP cable :)

• It has four pairs of wires inside the jacket which are twisted.
• Reason: To eliminate interference such as noises from adjacent pairs and also other electrical devices.
• There are actually five categories of this UTP cable and each and every one of it has its own application.
• Maximum cable: 100 meters. 

2) Shielded Twisted Pair Cable (STP)

This is STP cable.

• There are two wires wrapped in a foil shielding to help provide more reliable data communication.
• This means it is clearer compared to UTP cable. 
• Transfer data in the form of current.

3) Co-axial Cable

And this is co-axial cable ^^

• Co-axial cable has a single copper conductor at its center.
•  Transfer data in the form of current.
• Usually applied with microwave transmission, computer and instrumentation data connections.
• The inner conductor might be solid or stranded. However, stranded inner conductor is more flexible.

4) Fiber Optics Cable

Fiber Optic Cable

• This transmit light rather than electronic signals which eliminates the problem of electrical interference.
• It is ideal for certain environments which protects the electronic flow.
• Fiber Optic Cables transmit signals over a much longer distance and it has the maximum length of 2000 meters.

In this week's lecture, there was also a presentation from two groups regarding the topic of BLOGGING as well as SEARCH ENGINES. Both of these presentations were attention-grabbing as somehow, it helps me to do any tasks in my daily activities. Well, it is actually an addition of new knowledge and so I loved it. ^^ 

And with that, have fun scrolling through! 

Till next time ^^

Topology, Protocol and Architecture

NETWORK TOPOLOGY: The study of the arrangement or mapping of the elements of a network especially the physical and logical interconnections between nodes.

PHYSICAL TOPOLOGY: The physical layout of devices on a network and the way the workstations are connected to the network. 

LOGICAL TOPOLOGY: The mapping of the flow of data between nodes. 

TOPOLOGY

Linear Bus Topology

Above is the linear bus topology and it consists of a main run of cable with a terminator at each end. The protocol that can be used with this topology are Ethernet and LocalTalk.

Star Topology

For star topology, each node is connected to a hub or a connector. Similar to linear bus topology, it is applied to a protocol such as Ethernet and also LocalTalk. 

Ring Topology

As for ring topology, each of the system is connected to its respective neighbor forming a ring. However, if one of the workstations or nodes are disabled, therefore, the whole system would be disabled. FDDI (Fiber Distributed Data Interface) is one of the protocol that uses ring topology in its systems.

Tree Topology

Tree topology combines features of linear bus and star topology. Tree topology is also known as hybrid.

PROTOCOL

Protocol is a set of rules that governs the communication between computers of the network. 

Examples of protocol:

1. Ethernet

2. LocalTalk

3.Token Ring

4. TCIP/WAP which is for the internet

5. WiFi

6. Bluetooth

ASYNCHRONOUS TRANSFER MODE (ATM)

• A standard switching approach constructed to unify telecommunication and computer networks.

• Uses asynchronous time-division multiplexing and it encodes data into a small and fixed-size cells compared to Ethernet protocol that uses packets or frames. 

Hope you readers had fun absorbing all the new information and knowledge. Till next time! ^^ 

Introduction to Networking

First and foremost, the idea of networking is actually as old as telecommunication where this can actually become evident through the times of the stone age. Want to see an example? 

Here's a situation:

Caveman A wants to invite Caveman B over a game of hurling rocks at each other, but they live too far from each other. In this case, in terms of communication, it is difficult for two of these cavemen to contact each other as during these days, communication was not in an advanced state, unlike this era. So, in your point of view, what are the options that could be taken in order to communicate with each other?

Well, some of it are:

1. Caveman A to walk over at Caveman B's place.
2. Get a bigger drum so that Caveman B would be able to hear.
3. Ask Caveman C, who lives halfway between them to forward the message. 

So, as you readers can see, back in the olden days, communication was considered very difficult. However, for us nowadays, everything has become so easy for us especially in terms of networking. ^^

NETWORK : A collection of connected intelligent computing device or between two computers by direct cabling which is the basic network.

NETWORKING : The practice of linking two or more computing device together for the purpose of sharing data.

Basic Network : Connected by a cable to allow exchange of data. 

Next, I am going to introduce to you readers four new terms which are LAN (Local Area Network), WAN (Wide Area Network), MAN (Metropolitan Area Network) and last but not least, PAN (Personal Area Network). 

LAN or Local Area Network is actually confined to a relatively small area and are generally limited to a geographic area such as labs, schools and buildings.

WAN or Wide Area Network, on the other hand, connects to larger geographic areas such as Johor Bahru, Malaysia and also the World. This is actually more complicated if it is compared to LAN. Adding on, this type uses multiplexing in order to connect the local and metropolitan networks which is via hybrid network.

MAN or Metropolitan Area Network is a network that links user with computer contrivance in a geographic zone or region larger than LAN but smaller than WAN.

PAN or Personal Area Network is the join of information technology devices in the range of one single person, usually within the range of 10 meters. This particular type of network applies some pattern of wireless technology. WiMax, 3G and wireless broadband are examples of PAN.  

NETWORK ELECTRONIC DEVICES

BRIDGE: A bridge device filters data traffic at a network boundary. It reduces the amount of traffic on a LAN by dividing it into two segments.

Routers: A device that forwards data packets between computer networks, creating an overlay internet work. A router is connected to two or more data lines from distinctive networks.

HUBS: A device for connecting multiple Ethernet devices together and making them act as a single network segment.

GATEWAYS: A gateway is a network point that acts as an entrance to another network.

In today's lecture, I think there were many new and different terms regarding network and telecommunication that was exposed to us. By posting into this blog, it could actually help me to understand thoroughly about the topic because I could search and discover myself a deeper meaning and explanation about this particular topic. 

Hope you readers enjoy reading this post. Till then! ^^ 

Reflection Number Two

Assalamualaikum and hello hello there my dear readers! 


This is the second entry and i hope you readers are looking forward to read it as more and more new knowledge would be spread out through this particular site. As for this entry, we are moving on to the second lecture of this subject which was on the topic of DATA COMMUNICATION.


As we all know in the means of data communication, it involves mostly the use of computers, no matter where and how it is used. Computers are now made useful in every single ways and paths of life. Below we can see that computers are used in various places.

The children in schools uses computer 

Not to forget, even in universities ^^

All of this is due to the need in the process of transferring files from one computer to another in order to access a variety of information. In other words, for you, readers', information, this is also known as a mechanism of exchanging data. 


Let's move deeper into this topic and we will discover what it means by data communication. Basically, after the lecture, what I discovered was that data communication is defined as the collection and distribution of the electronic representation of information from and to remote facilities by means of electrical transmission system. For example, the electrical transmission can be through telephone lines, satellites and also coaxial cable. Have you guys ever heard of something called RAW DATA/INFORMATION? Well, when I saw this word, it somehow came to my mind that I've heard of it somewhere and at sometime in my life which I don't remember. For your information, this term actually means the information that could appear in a variety of formats. For instance, data, text, graphics, voice and still pictures and these formats must be digitized.

TYPES OF SIGNALS

From what I've learnt in the lecture, there are two types of signals that are needed to be converted from one to another which are Analogue Signal and Digital Signal.

You see the difference between the two waves? ^^

ANALOGUE SIGNAL	DIGITAL SIGNAL
-An example: Human voice -Analogue signal or wave is formed by continuously varying voltage levels that create a wave that can be grasped by an analogue transmitter like a microphone.	-Digital signal is a transmission of binary electrical or light pulses that only have two possible states which are 0 and 1. -0 and 1 are the language of computers.

Note: The process of changing the analogue signal to a digital signal is known as MODULATION.

          The process of changing digital signal to an analogue signal is called DEMODULATION.

BINARY DIGITAL

Alright readers, let's move on to a small partial of this topic where it is regarding the binary digit or we also call it bit. Do you guys want to know something? This thing that you call bit are actually the basic or the smallest unit of measurement in a digital wave. Data capacity, does this term ring the bell? Here's a little info for you readers to have a quick glimpse at, the bit or also known as data capacity.

8 BIT = 1 BYTE

1000 BYTE = 1 KILOBYTE

1000 KILOBYTE = 1 MEGABYTE

1000 MEGABYTE = 1 GIGABYTE

1000 GIGABYTE = 1 TERABYTE

DATA TRANSMISSION MODE

Did it ever cross your mind on things about the transmission of data and how many ways it moves? I suppose not everybody is aware of this matter, so was I before I learnt this. Well, if you readers want to know, there are generally two patterns of data transmission that was taught by Dr Dayang, my lecturer. Firstly, it's parallel transmission where the group of bits as mentioned on top is transferred simultaneously by using a separate line for each and every bits. The second transmission mode is serial. In this case, the bits are transmitted one after the other on a single line and this is slower compared to the parallel transmission. 

Moving on, synchronous and asynchronous are the ways of transmission for the serial pattern. I will only write on how the asynchronous transmission works as this is the one that mostly catches my interests. Unfortunately, I know that dragging the explanation would make this so dull so tadaaaaaa! I provide you readers with some pictures, so give it a sight okay! ^^

Skype! It's one example that undergoes asynchronous transmission.

Not leaving out this- Video Conference. :)

DATA FLOW

Simplex, half-duplex and full duplex, these are the three distinctive operations that takes place during a data flow which happens between two pieces of equipment. 

Simplex: Data is transmitted in one direction only.

Half-duplex: The message can flow in two directions but never at the same time.

Full-duplex: Both station can transmit and receive the information simultaneously.

Walkie Talkie- An example of half-duplex.

Radio experiences simplex operation

Hope you readers have enjoyed reading and scrolling through this page as to add up to your buckets of knowledge. As for me, I am really looking forward to my next lecture and share with others the input that I have gained. Till then, happy reading folks! ^^