Friday, 23 March 2012

Introduction to Networking...^^

Wednesday, 21st March 2012

Our class last week was cancelled, so this week was the third lecture conducted by Dr. Dayang. ^^

This time, we proceeded to another focus of this subject, which was Networking. Dr. Dayang had introduced Networking to us. 

At first, Dr. Dayang reminded us to keep these few things in mind : -
1.)  Elements of Computer
·         IPOSK (Input; Processor; Output; Storage; Communication)
2.)  Elements of Computer and Communication Technology
· People; Procedure; Data/Information; Hardware; Software;      Communications/Connectivity
3.)  Elements of Networking
·         Terminals, Workstations, Computers, and other devices
·         Transmission Media
·         Network electronics
·         Software
·         Network Architecture Standards   

Personally, I felt that repetition was one of the strength of Dr. Dayang. Since the elements above were more or less the same, thus, Dr. Dayang had repeatedly mentioned about those elements so that we were able to differentiate them. In fact, I prefer repetition especially for information that is easily confusing.
Next, I understood that the Networking concept was started since the stone ages whereby human being started to learn to communicate with others that were far apart. It was the basic networking concept.

Computer Networking
Basically, there are two definitions for Computer Networking : -
1.) The connection between two computers by direct cabling. Cabling refers to connection that uses cable.
2.) Connection of computers and other hardware devices to share hardware, software, and data as well as to communicate with each other.

The main purpose of Computer Networking is to share data within different devices.
When we were discussing the sharing of data, Dr. Dayang related it to the transmission of data that we learnt in last lecture.

What is transmitter?
Transmitter = Source of message = Sender
Destination = Receiver

Moving on to the next point, I would like to share about Server. According to Dr. Dayang, server is a specialized computer that controls the sharing of data among a network of computers. There are several functions of server.

1.)  Regulate Internet traffic between all of the computers
2.)  Store all of the important fioles that many computers need to use in one central place
3.)  Let multiple computers access the same printer or scanner (usually the connection to these output devices are secured)

The above functions can be achieved by the aid of Local Area Connection (LAN)

Next, I would like to share about the Networking Classification.
 


Then, Dr. Dayang had explained about Internet Protocol.
Internet Protocol refers to the rules to send and receive messages by using Internet Protocol Address (IP Address). After listening to Dr. Dayang’s explanation, I realized that every computer has their unique IP Address although they are not the same model. I wonder how the system can create the address in a systematic arrangement as computer users are all over the world.

Coming up next was the Transmission Media that enabled sharing of data occurred. Transmission Media classified into 2 groups, they are Bounded Media and Unbounded Media. Bounded Media refers to physical link that use to transfer data such as Twisted Pair Wire, Co-axial Cable and Fiber Optic Cable.  Meanwhile, Unbounded Media refers to abstract link (air / vacuum) that use to transfer data such as Microwave Radio, Infrared Signals and Satellite Communication.

Later on, we learnt about Network Electronic Devices. I understood that Network Electronic Devices are devices that control data transmission from sources to destinations.
There are several devices that I would like to focus on our sharing.
 
Hub : A device that connect several computers together so that these computers can share their data through a single LAN system.

* Hub




Bridge :  A device that connect a LAN to another LAN that use the same protocol in order to share data with each other. 
* Bridge


Router : A device that enables data to be transmitted at overlay internetwork. 
* Router

Gateway : A point where two or more networks connect. 


Comparison Between Hub, Bridge, Router and Gateway

 
Aspects
Hub
Bridge
Router
Gateway
Network involved
A single LAN
More than one LAN
Multiple LAN or WAN
WAN
Ability to connect  networks with different protocol
-
No. Connected Networks must have same protocols.
No. Connected Networks must have same protocols.
Yes. Able to interpret and translate the different protocols.

I hope that Dr. Dayang can explain more on these Network Electronic Device during next lecture because I quite confused with the functions of these devices. 

That's all from me. ^^

Thursday, 8 March 2012

Deeper Knowledge on Telecommunication & Networking


Hi all, it's time for the second reflective journal!

As usual, I am going to share my understanding towards the second lesson of Telecommunication & Networking.

Wednesday, 7th March 2012
It was a lecture regarding Data Communication. It sounded easy to understand, but in fact, it was too abstract for me to figure out.
Basically, we had been taught on these few topics  :        
1.0) Data Communications
                         1.1) Data Representative : Analogue & Digital Signal
                         1.2) Data Representative : Binary Digits
2.0) Data Transmission Mode
                         2.1) Parallel Transmission
                         2.2) Serial Transmission
                                2.2.1) Synchronous Transmission
                                2.2.2) Asynchronous Transmission
3.0) Data Flow Styles
                          3.1) Simplex
                          3.2) Half-Duplex
                          3.3) Full-Duplex
4.0) Multiplexing


Why I arranged those topics into point forms? This was because this method enabled me to have an overall idea on the knowledge that I had learnt. To me, it is quite useful especially when I need to memorise piles of notes. It enables me to have a clear idea on the contents.
So, let's start our sharing. ^^

At first, we had been introduced to the definition of Data Communication. This is all about how the data/information is being collected and also transmitted to other places including remote area. How could these processes be done? After Dr. Dayang’s explanation, I knew that those processes are done through electrical transmission system. It is simply a system that enables data to transmit through it and send to other communication media like computer. The examples of this system are telephone lines, satellites or coaxial cable.

Let's move on to the next point - Data Representative.
Last week I did mention that I couldn't understand the meaning of Analogue Signal and Digital Signal. Fortunately, these two terms were taught in this lecture.

Basically, I understood that these two terms are different forms of data representatives. The information below are the summary of Analogue Signal and Digital Signal.

Analogue Signal     -     Represent data with continuous waves
-           Examples : Human voice and music in their natural form

 


Digital Signal          -     Represent data in the form of 1’s and 0’s (Binary Digits Coding 
   System)
-            Example : Softcopy of Word Text in computer


 



Later on, I was introduced to the word MoDem. Most of us know that modem is needed for Internet access. In fact, there are other functions of MoDem. This hardware possesses components that are able to convert Analogue to Digital Signal (Modulation) and also Digital to Analogue (Demodulation). That’s why this hardware is named MoDem. 





           

To illustrate the conversion, let us take recording by MP3 audio player as an example.




1.) Human voice (represent by Analogue Signal) is the input of the MP3 player. Recording is started.
2.) Analogue-to-Digital Converter (ADC) inside the MP3 receives the Analogue Signal and converts the Analogue Signal to Digital Signal (combination of 1’s and 0’s).
3.) Conversion is completed. Human voice in digital form is saved in the memory of MP3.
4.) During playback of the human voice, digital signals are converted back to Analogue Signals through the Digital-to-Analogue Converter (DAC).
5.) Human voice in analogue form is transmitted through the speaker system.
6.) Human voice can be heard. 


Coming up next is the introduction of Byte. It sounded familiar right? What about Kilobytes or kB?
Through my understanding, I knew that Byte is actually the smallest unit of data capacity. We always ask data storage device like pen-drive or thumb-drive are printed with units like kB, MB, GB and so on. 

So, here is the relationship of Byte and Binary Digits.

Let say I key in the alphabet “A” into the computer.
“A” is represented by a series of digits 1100 0001 in computer.
Thus, we can say that             
1 alphabet/character = 8 digits = 1 byte
·         Prefixes like Kilo- , Mega- , Giga- and Terra- are representing the different amount/size of the data.



After exposing to the basic ideas of data communication, I was able to understand the Data
Transmission Mode.
There are two different modes of transmission that can be illustrated by the diagram below.



Serial Transmission : Bits are transmitted one by one in a single line.
                                                         
Two type of Serial Transmission ( Let text as the example for the explanation) : 
o   Synchronous Transmission – Words (Data) are transmitted in groups
o   Asynchronous Transmission – Transmission done through alphabet (1 byte) 
        by alphabet (1 byte)

 
                            

·        Parellel Transmission : Bits are transmitted in bytes in separated paths.


From the above figure, I can imagine that Serial Transmission is slower than Parallel Transmission as there is only 1 path for 8 digits to transmit through.


At the end of the class, I also introduced to different styles of data flow.



That’s all for my sharing!! ^^





Friday, 2 March 2012

First Date with Dr. Dayang ^^

Hi everyone...I've been thinking of creating a blog for some personal reasons but I didn't expect that I will start it with academic purpose. It's quite interesting to write a journal reflection through the mean of blogging. Honestly, I prefer this kind of assessment rather than submit a piles of written journals. I'm sure that there may have a bunch of coursemates that share the same feeling with me....^^ 

So, here is my Journal =)

Wednesday, 29th February 2012 

At the beginning of the lecture, Dr. Dayang gave us the instructions of our assignments...( Arrrgghhhh....assignmentsSSS). Then, there's a pop-up question from the floor : " When is the due date of this assignment? " . Dr. replied that there has no due date for this assignment. Following that, my coursemate, Ekin said, "But we need due date...". Haha....I quite agree with Ekin as "due date" motivates us to complete our task immediately and also enable us to manage our time well. I'm sure that most of us experience the same thing. When there is a deadline, things could be done effectively. 

So, what I've learnt throughout the whole lesson?

It's the Introduction of Telecommunication !!

You may ask, "Is there any difference between Telecommunication and Communication??"
Ofcourse, there are some differences. 

So, our lecture began with Communication followed by Telecommunication

Through my understanding, most of us may think that communication is the transfer of messages between speaker and listener. However, it is not that surface.

Let me clear your doubts. Basically, for communication to be occurred, the listener should has the ability to understand the meaning of the message that sent by the speaker. Dr. Dayang gave us some interesting examples :-

1.) When you are talking to your pet and your pet is able to response to you, then it considers as COMMUNICATION because the listener understand the meaning of the speaker;

2.) When you are listening to a radio broadcast and you get the message that the DJ wants to deliver, even though you're not with him/her, this is still COMMUNICATION because you, as a listener, understand the meaning of the speaker;

HOWEVER,

3.) When you try to act as an environmentalist and talk to a tree, this is definitely NOT COMMUNICATION. WHY ??? This is because the tree, as a listener, is not able to understand your message.  

So, there's several points to be remembered : - 

Communication - the listener must be able to understand the message, and ofcourse, for the listener to understand your message, your content must have meaning

 Let's move on to the next topic that I would like to share with you all --- the Communication Model.

To make life easier, I would like to share a video that I found quite useful for us to understand the overall process of Communication Model.

video

After watching this video clip, I was able to understand another communication model which is The Shannon-Weaver Mathematical Model, 1949 also. They are quite similar to each other.
Later on, I managed to understand the meaning of Telecommunication also. I found it easier for me to memorise the meaning through this way : -




Tele- = over a long distance

Thus,

Tele-  +  Communication = communication over a long distance 





To understand deeper on this topic, Dr. Dayang had introduced The Elements of Computer and Computer Technology to us. 

In short, I learnt that when we discuss about the elements of computer and computer technology, we need to clear that these elements are different from the elements of computer. 

There are overall five main elements in computer : -
                I    - Input
                P   - Processor
                O   - Output
                S   - Storage 
                K   - Communication ( K = Komunikasi in Malay Language )

Meanwhile, for The Elements of Computer and Computer Technology : - 
                People         - Professionals in this field + End users ( users of computer )
                Procedure    - Steps / Sequences
                Data / Information
                Hardware     - Any physical objects that are part of the computer system
                Software      - Abstract things that controll functions of the computer 
                                     ( System software  -  Microsoft Windows, Mac OS X, Linux... )
                                     ( Application software - Adobe Reader, Microsoft Office... )
                Communications / 
                Connectivity - transmission of data ( from analog-to-digital / digital-to-analog )

* Do you think that computer users nowadays getting younger ??                     




 



When I revised the lecture notes, I found that I couldn't understand the meaning of analog and digital. So, I wish I could find out the answer when I see Dr. Dayang during the next lecture. ^^

Wow...I think I'd explain too much on the first lecture. So how about my feelings after the very first lecture??? =)


Basically, I am looking forward to the coming lecture because my first impression towards Dr. Dayang was that she is an effective and also responsible lecturer whereby she did her powerponit slides well with simple yet informative design. Her sense of humour is also another thing that most of our coursemates like. I think we will have a great time with Dr. Dayang throughout the whole journey in this subject. ^^

That's all from me. Thanks for reading my lengthy post ^^ !