Jun 2, 2012

#Reflection 8

Assalamualaikum. 


Hello everyone! :D
This is going to be the last post in this blog. 


Today, we will go through a quick and simple reading on INTERNET INFRASTRUCTURE


Internet Infrastructure is a hierarchy of network:

  • From single computer to LAN
  • From LAN to ISP (Internet Service Provider)
  • From ISP to WWW (World Wide Web)

In order to connect all of these, you need:
  • computer
  • web browser
  • internet access

Next, let's take a look at INTERNET PROTOCOL (IP)

  • IP provides a common layer over dissimilar network.
  • It is also a standard protocol to connect LAN.
  • It also functioned to move packet among host computer through gateways
  • Every computer assign  unique IP adress.

The IP adress:
  • Divided into 2:
    • Identifying the network
    • Identifying the node/host
  • Consist of 32 bits
  • Shown as 4 octets of numbers from 0-225 represented in decimal form instead of binary.

eg: 10101110 = 1 octet (8 binary)

eg: 168.212.226.204 = Decimal form (4 octet = 32 binary)

  • Class of addresses determines which part belongs to the network address and which part belongs to the node.
  • All nodes on a given network share the same network prefix but must have a unique host number.
Example:

CLASS A NETWORK
  • Binary starts with 0
  • Decimal number can be anywhere from 1-126
  • The first 8 bits identify network
  • Other 24 bits indicate the host within the network
CLASS B NETWORK
  • Binary starts with 10
  • Decimal number can be anywhere from 128-191
  • The number 127 is reserved for loop back and is used for internal testing on the local machine
  • First 16 bits will identify the network
  • Other 16 bits indicate the host
CLASS C NETWORK
  • Binary starts with 110
  • Decimal number can be anywhere from 192-223
  • The first 24 bits identify the network
CLASS D NETWORK
  • Binary starts with 1110
  • Decimal number can be anywhere from 224-239
  • This type of network usually used to support multicasting.
CLASS E NETWORK
  • Binary starts with 1111
  • Decimal number can be anywhere from 240-254
  • Used for experimenting
  • Never been documented or utilized in a standard way. (-__-")




DOMAIN NAME SYSTEM (DNS)

It is a type of internet service that translate domain names into numerical address.

Eg: www.yahoo.com => into 204.62.131.129


Why use DNS? = It is easier to remember because the names are alphabetic :D


INTERNET SERVICE PROVIDER (ISP)

The ISP is the company that will provide the internet service to public.
  • Example of ISP in Malaysia is like the one for broadband;
    • TM Net
    • Streamyx
    • P1
    • Celcom Broadband
    • Maxis Broadband
HYPERTEXT TRANSFER PROTOCOL (HTTP)

HyperText Transfer Protocol is the underlying protocol used for the World Wide Web.
  • It defines how messages are formatted and transmitted.
  • Determine what actions should be taken by Web servers and browsers to response to various commands.
HTTP also called as a stateless protocol because each command is executed independently, without any knowledge of the commands that came before.


That is why it is difficult to implement Web sites! :O

Other new technologies such as Java, JavaScript and cookies has been invented to encounter the HTTP shortcomings.



That is all for now. Till then, I'm going to miss Dr Dayang so much. She is so warm and cheerful all the time. I hope our path will intersect later in the future.

Have a sweet day, all!

Toddles! :) 










May 13, 2012

Reflection #7

Wireless Technology


Dr. Dayang has proceeded the topic about wireless technology but unfortunately I couldn't come to class :(


Nevertheless, here is my entry to wrap up about the wireless technology. Well, I did some revision on my own about this topic.


WIRELESS

  • Wireless telecommunications networks are a type of information transmission system that uses electromagnetic waves.



BLUETOOTH
The Bluetooth logo



  • Bluetooth is an industrial specification for wireless personal area network or PANs.
  • Bluetooth is acceptable for situations when two or more devices are in proximity to each other and don't require high bandwidth
  • The distance covered only a very short range which is less than 10 meters. 
  • Devices involved : mobile phones, laptops, PCs, printers, digitial cameras and video game consoles. 

The devices that use Bluetooth can be connected to the laptop as well.




INFRARED DATA TRANSMISSION

The IrDA logo.
  • IrDA (Infrared Data Association) is a technology where we can transfer any files from any devices by using infrared light, the one that is non RF.
  • The characteristic of infrared transmissions are: 
    • The power to transfer data is not so high.
    • Only can transfer in a short range, for example the remote control.
    • Mainly attached to mobile phones to transfer the data or files from one to another.
  • Nevertheless, many laptops sold today are equipped with an IrDA-compatible transceiver that enables communication with other devices, such as printers, modems, LANs, or other laptops.
  • However, the limit of transfer speed ranges from 2400 bps to 4 Mbps.
  • Requires line of sight transmission.
The various devices that can transfer files and data by using infrared communication.


BROADBAND TECHNOLOGY

  • It refers to a telecommunications signal or device of greater bandwidth with greater the information-carrying capacity.
  • Today, broadband is widely use to enable the internet access to laptop and mobile devices.
  • The device that is simply used is the broadband stick with different service providers.
The different service providers in Malaysia.

  • Mobile broadband allows for mobility so that the user can get internet access where ever there are. However, it depends on the service provider's coverage as well.
  • Fixed broadband are mainly used for home or business and more stable because it uses cable and usually runs on fibre.

Router




May 5, 2012

Reflection #6


UNBOUNDED MEDIA / UNGUIDED MEDIA

  • The media transport electromagnetic wave without physical conductor.
  • Signal are broadcasting through air which means it is available to anyone who has device that capable of receiving the signal.


TERRESTIAL MICROWAVE
  • It requires line of sight transmission and reception equipment.
  • The taller the antennas, the longer the sight distance.
  • Make tower on the hills or mountain to be higher than the ground.
  • The signal transferred one way at a time.
To increase the distance, a system called repeater can be installed with the antenna.


2 TYPES OF ANTENNAS:

  1. Parabolic dish
  2. Horn


PARABOLIC DISH






  • Based on geometry repeater of parabola.
  • Works like a funnel (catching a wide range of waves and directing to a common point called focus)
  • This is used by line namely maxis celcom and digi to catch the data.

HORN




  • Looks like a gigantic scoop
  • Outgoing transmission are broadcast up to a stern and deflected outward in a series of narrow parallel beams by the scooped shaped of the horn.
  •  
SATELLITE






  • Same principal as the terrestrial microwave
  • Super tall antenna and repeater
  • Single bounce
  • Capability = any location on earth no matter how remote
  • High quality communication without requiring a huge investment in ground-based infrastructure.

Now let see the equipment used and distance covered of four transmission:
  1. RADIO FREQUENCY
  2. CELLULAR PHONE
  3. WIFI
  4. BLUETOOTH
The equipment used and distance covered of four transmission:
 

RADIO FREQUENCY
  • The rate of oscillation in the range of about 3 kHz to 300 GHz.
  • Corresponds to the frequency of radio waves, and the alternating currents which carry radio signals.
  • Antenna must be used to received the signal.
  • Usually done via a resonator – a circuit with a capacitor and an inductor forming a tuned circuit.
  • Resonator act as amplifier to the oscillations within a particular frequency band
  • It also reducing oscillations at other frequencies outside the band.

 

CELLULAR PHONE
Cellular phone is using various transmission

1G  
  • 1G is short for first-generation wireless telephone technology.
  •  This generation of phones and networks is represented by the brick-sized analog phones introduced in the 1980’s.
  •  Subsequent numbers refer to newer and upcoming technology.
2G  
  • 2G phones use digital networks.
  • 2G networks and their digital nature also made it more difficult to eavesdrop on mobile phone calls.
3G 
  • 3G networks are an in between standard. 
  • 3G is seen more as pre4G instead of a standard of its own. The advantage 3G networks have over 2G networks is speed.  
  • 3G networks are built to handle the needs of today’s wireless users.
  • This standard of wireless networks increases the speed of internet browsing, picture and video messaging, and handheld GPS use.
4G 
  • 4G (AKA Beyond 3G) is like the other generations in that its advantage lies in promised increased speeds in data transmission. There is currently no formal definition for 4G, but there are objectives.  
  • One of these objectives is for 4G to become a fully IP-based system, much like modern computer networks.  
  • The supposed speeds for 4G will be between 100 Mbit/s and 1 Gbit/s.

WiFi

  • WiFi is the original technology of wireless local area network or WLAN.
  • It is usually based on IEEE 802.11 specifications.
  • 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.

All in all, we already used all these transmission and the evolution of these transmission are still going on today. Maybe in future, we might have a new technology that way more intelligent than today. Who knows?


Apr 26, 2012

Reflection #5

This week, the topic that has been focused is about cabling. What is cabling? We'll see the meaning and types of cabling for internet with further reading. 

WHAT IS CABLE?


Cable is the medium through which information usually moves from one device to another.

There are five types of cables that we will go through:


1. Unshielded Twisted Pair (UTP) Cable
2. Shielded Twisted Pair (STP) Cable
3. Coaxial Cable
4. Fiber Optic Cable
5. Wireless LANs

The different types of cables are divided into two categories, the guided and unguided.

Unshielded Twisted Pair (UTP) Cable


  • Has four pairs of wires inside.
  • Each pair is twisted with different numbers of twists per inch.
  • The advantage of twists: to help eliminate noise from adjacent pairs and other electrical device.
Shielded Twisted Pair (STP) Cable



  • Consist of two individual wires wrapped in a foil shielding.
  • The cable is quite bulky.
  • Usually used for Token Ring topology.


Coaxial Cable



  • Has a single copper conductor at its center.
  • Insulation of plastic layer between the center conductor and a braided metal shield.
  • Function of metal shield: block any outside interference: 
    • Fluorescent light
    • Motors
    • Other computers

Fiber Optic Cable



  • A center glass core is surrounded by several layers of protective materials.
  • Transmit signals over much longer distance.
  • Move in a form of light.
  • Capable of eliminating the problem of electrical interference.



Apr 8, 2012

Reflection #4

This week, we are introduced deeper to three integral part in networking:


  • Topology
  • Protocol
  • Architecture



Network Topology is the study of the mapping of elements of a network between nodes


This includes the physical and logical interconnection of the network. Topology is divided into two type:
  • Physical Topology (real)
  • Logical Topology (virtual)
Physical Topology is the way devices are arranged and communicate with each other.

Logical Topology, on the other hand, is the mapping of the flow of data between the nodes in the network determines the logical topology of the network.


There are many types of topology but for now, we had learned few of them:
  • Linear bus
  • Star
  • Ring
  • Tree








Linear bus topology consists of a main run cable with terminator at each end. In this type of topology, the nodes are connected to linear cable. The Ethernet and LocalTalk networks usually use this type of topology.

Star topology connecting each nodes directly to a central network hub or concentrator. The data on a star networking will passes through the hub or the concentrator. These hub and concentrator are also known as repeater for the data flow.

Now, let see how the ring topology works. Each of the system in ring topology is connected to its respective neighbour thus forming a ring. On the diagram above, we can see how all the nodes are connected in a form of circular motion. The ring topology does not require termination because all nodes connected in a loop, which means no beginning and no end point.

The tree topology is a combination of star topology that connected to a linear bus backbone cable. It is also known as hybrid. This type of topology will allows the expansion of an existing network.

Protocol
It is a set of rules that governs the communications between computers on a network.


There are many types of protocol:
  • Ethernet - Logical linear bus topology protocol
  • LocalTalk - Star topology protocol
  • Token Ring - Ring topology protocol
  • TCP/IP and WAP
  • WiFi
  • Bluetooth



Asynchronous Transfer Mode (ATM)

  • It is a standard switching technique to unify telecommunication and computer networks.

  • ATM is quite different than Ethernet that used variable size of frames, it uses asynchronous time division multiplexing that will encode data into small and fixed-sized cells.

Mar 21, 2012

Reflection #3


Today's topic is Introduction to Networking and we are reminded to differentiate the difference between telecommunication and networking. first and foremost, Dr. Dayang gave us an example of networking from the stone age where the situation is Caveman A wanted to invite Caveman B who live too far away from him for a game of hurling stone to each other. Caveman A cannot use a drum because it cannot be heard. We have to give suggestion on how to solve the problem that Caveman A encounter. Finally, she gave out few solutions ;

Walk over Caveman B
Get a bigger drum
Ask Caveman C who lived halfway between them to forward the message

Voila! There we have a simple idea of networking before we proceed to the technical meaning of networking. Basically, networking means a collection of connected intelligent computing devices. The basic networking is a connection between two computer by direct cabling.

Besides that, networking also means connecting a computer with other computer or other devices to enable them to communicate with each other.

There are four popular networks in used:

LAN (Local Area Network)
WAN (Wide Area Network)
MAN (Metropolitan Area Network)
PAN (Personal Area Network)


LAN is usually used in small area and limited to geographical area such as computer lab, school and building. This network is rarely used for more than a mile apart. A typical LAN such as in a computer lab usually use one computer as a server functioned to control the network shared by all computers attached to it. The are two ways of connecting LAN which are:

Bounded (by using cable)
Unbounded (without using cable or known as wireless)



Mar 9, 2012

Reflection #2


Greetings, future teachers!


This week, Dr. Dayang is getting us into the topic about data communication. In a world where we are about to set off in a brisk pace, changing data in a faster way in quite a convenience. That is why we need the access of data communication. Data communication is the collection and distribution of the electronic representation of information from and to remote facilities by means of electrical transmission system.

Among all the data, the data in form of text, voice and still pictures are known as RAW DATA or RAW INFORMATION and they must be digitized to be transmitted through computer. The raw data need to be convert into signal so it can be understood by the communication media as for the data to be transmitted.
Here, there are two forms of signal which are analogue signal and digital signal.







The differences between analogue signals and digital signals.


These two signals will carry out two process on conversion:
  • Analogue to digital = modulation
  • Digital to analogue = demodulation





To make it simple, the conversion of analogue to digital is merely because digital signal is the language of the computer. Here is one example of these two conversion:



The conversion that occurs between a microphone and a speaker.


The hardware that is used in computer to do this process is called MODEM as the combination of the word modulation and demodulation.




Let's move on to the data transmission mode, shall we? There are two types of transmission :


Parallel transmission and Serial transmission







By looking at this figure, I am sure that you can already guess the meaning of both transmission, right?


Bits, or binary digits consists of Byte, Kilo, Mega, Giga and Tera. One bytes is equal to 8 bits.

Based on the figure above, the serial transmission is a bit slower than the parallel transmission because it obviously transmits all the bits one after another on a single line.




Under the serial transmission mode, there are two types of transmission:
  • Synchronous transmission
  • Asynchronous transmission.







The synchronous transmission is a large group of data that is transmitted in blocks called frame.

On the other hand, the asynchronous transmission is the bits that are divided into small groups in form of bytes and send independently. This means a groups of bits can be sent at any time and the receiver will never know when they will arrive.

Here are some examples:






The synchronous transmission is Now, moving on to the data flow. The process of exchanging can be done in three operation style:


  • Simplex
  • Half-duplex
  • Full-duplex

The simplex operation is when the data is transmitted in one direction only. As much as I
understand about it, the role of transmitter and receiver are fixed.


For example, when you are watching television or listening to the radio where you as the receiver only got to understand the message or information without reacting back to the sender.

The half-duplex operation is when the transmission can flow in two direction but never at the same time. The nearest example is the walkie talkie.



Last but not list, the full-duplex operation is when both station can transmit and receive the information simultaneously. it is usually consist of two simplex channel, for example the the online chatting.




As much as I concern, the lesson learned this week mostly introduced me to the information on how the network performed in the internet and from the computer. This actually make me a computer literate as I understand what is happening throughout the process of transmission and receiving the information. I hope in the next class, I can grab all the information effectively as I am quite confused when it comes to computer learning. :D


Mar 2, 2012

Reflection #1




Assalamualaikum.
Hello there!

I don't want to make my blog look so lame that no one will ever read it but since it is one of my assignment, I have made a decision to relive my blog, revamped it a little bit and filled it with something proper; according to my Telecommunication and Networking subject, of course. This week Dr. Dayang is talking about the introduction to Telecommunication and Networking.

First, she let us guessing about the literal meaning of the words tele and communication. At first, we randomly answered and finally she heard the keyword. Tele means communication over a long distance while communication means the activity of expressing ideas or feeling or giving people information. Therefore, the whole meaning of telecommunication is sending a long distance message by using a transmitter which is the devices such as computers and telephone.



Hmm.. How about this?



Secondly, she moved on the topic that everyone would consider as hard to remember, the history of computers. I swear every one of us looks so blown away with the history retold by Dr. Dayang as we concentrate and jot down anything we could when eventually she told us that she is not going to ask us about history in the exam papers. What a relief! :D


Next, if you ever learned about Telecommunication and Networking or just simply live on Earth, you might want to know about the six elements of computer and communication.


1. People.



People are the most important element because they are the user who operate the computer. They are the one who built, analyse and develop the system. There are two types of people involved in communication. First, the professional people who have gone through specialized training in theory and technical aspect. Second is the end user or those who only know how to use without special training in the field.





Folks need to learn these thing as well, right?



2. Procedure.


 
Procedure is an ordered set of tasks for performing some action. It is the specification of operation which have to be executed in some way in order to attain the same result under the same situation. In this case, it is the procedure communicating so that the other receiver could understand the message.

Here is an example of procedure:






I don't think Dr. Dayang will like this. LOL.



3. Data.


 Data is the information stored in the computer system used by applications to accomplish tasks. We will get to that later because so far, this is all i understand about data.



4. Hardware.


Hardware can be considered as any physical object that are part of the computer system. Previously, we have learned that the basic operation of a computer system is IPOS. Input, processor, output and storage.



5. Software.


Every computer need software to make it function. Therefore, software is needed to start the communication. The Linux, OS system, Wimdows 7 and PDF application are all included in software categories.


6. Communication or connectivity.


The codec process, compression and decompression, which I vaguely remember in the class, is a part of communication process. It is the conversion of data analog-to-digital digital-to-analog

Dr. Dayang is such an awesome lecturer because she looks so calm and humorous at the same time. She explained everything in the simplest form ever and all I have to do is to remember the keywords. I love her starting from the first day when she decided to call me Shikin. Oh, how I have not been called with that name for quite a long time! I think I am getting used with the name of Ekin. I love it actually but then, she called me with that name and it sounds fine. It’s good to have another name now I guess, though I do not keen to be called as Shikin that much. But still, it is a part of my name anyway so, why not? :)