Day 3 - Wednesday, 21 March 2012

Hi everyone. Topic for today's lesson is Introduction to Networking. There are a few discussion for this topic. There are:

1- Introduction to Computer Networking

2 - The Importance of Networking

3 - Data Communication

4 - Introduction to Networking Devices/Equipment

5- Introduction to Networking Software

Computer Networking

A collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information.

Networking Component

Terminal, Workstations, Computers

Transmission Media

Network Electronics

Software

Network Architecture Standards

LAN = Local Area Network

Typical LAN configuration : one computer as a server

To store all of the software that controls the network and to share by all the computers attached to the network.

Cable connects to the server.

WAN = Wide Area Network

This kind of network is complicated. It uses multiplexing to connect the local and metropolitan network called hybrid network.

MAN = Metropolitan Area Network

A computer network that usually spans a city or a large campus. A MAN usually interconnects a number of local area networks (LANs) using a high-capacity backbone technology, such as fiber-optical links, and provides up-link services to wide area networks (or WAN) and the Internet. Similar to a LAN but typically over a larger area like a city.

PAN = Personal Area Network

* A network used to connect wireless devices (such as Bluetooth-enabled devices)

in close proximity to each other.

* An emerging technology that uses wireless communication to exchange data

between computing devices using short-range radio communication, typically

within an area of 10 meters.

* A computer network that supports wireless connections within a room or small area.

Server

A physical computer (a computer hardware system) dedicated to running one or more such services (as a host), to serve the needs of users of the other computers on the network. Depending on the computing service that it offers it could be a database server, file server, mail server, print server, web server, or other.

Multiplexing

Multiplexing is sending multiple signals or streams of information on a carrier at the same time in the form of a single, complex signal and then recovering the separate signals at the receiving end.

Hybrid Network

Hybrid networks use a combination of any two or more topologies in such a way that the resulting network does not exhibit one of the standard topologies. A hybrid topology is always produced when two different basic network topologies are connected. Two common examples for Hybrid network are: star ring network and star bus network.

Network Categorized

Topology (geometric arrangement of the network)

Protocol (common set of rules and signals the computers on the network use to communicate)

Architecture (peer to peer/client/server)

Bounded media

The physical links through which signals are confined to narrow path. Bounded media are made up of a external conductor(usually copper) bounded by jacket material. These are also called guided media.

Unbounded media

No physical connection is required. Space or air is the transmission medium for electromagnetic waves. Source and destination can be static or mobile. Broad spectrum from low to high bandwidth is available. Can be quickly implemented.

NETWORK ELECTRONIC DEVICES

Bridge

A Bridge does just what you would expect it to do - it joins two networks together so as far as data packets are concerned it looks like one large network. A bridge is not as capable as a Router - but it is less expensive.

Routers

A Router is a device that transfers data from one network to another in an intelligent way. It has the task of forwarding data packets to their destination by the most efficient route. In order to do this, the router has a micro computer inside it. This holds a table in memory that contains a list of all the networks it is connected to, along with the latest information on how busy each path in the network is, at that moment. This is called the 'routing table'. When a data packet arrives, the router does the following:-

	Reads the data packet's destination address
	Looks up all the paths it has available to get to that address.
	Checks on how busy each path is at the moment
	Sends the packet along the least congested (fastest) path.

Hub

The network 'Hub' allows computers to share data packets within a network.

Each computer will be connected to a single 'port' on the hub. So if you purchase an '8 port hub', you will be able to connect up to eight computers together.

You can also 'daisy chain' hubs to allow even more computers to join the network.

Gateways

A gateway converts the data passing between dissimilar networks so that each side can communicate with each other. i.e converts data into the correct network protocol.

The gateway is a mixture of hardware components and software.

This is unlike a standard 'Bridge' which simply joins two networks together that share the same protocol.

My opinion:

In my opinion, networking really helpful in our daily life. It makes us easy to connect with other people. Other than that, it benefits us in terms of works. The main thing is that it is very exciting to explore networking. There are too many tools that I do not know. I use it but i do not know the exact name of the tools. It is such a waste if I do not grab this knowledge.

That is all for today's lesson. I'll continue next week.

Day 2 - Wednesday, 7 March 2012

Hi everyone. I am here again. Let's continue on today's lesson. Basically,topic for today is DATA COMMUNICATION. There are four objectives for today's class:

• to define data communication terminology
• to detail the type of signal transmit through communication medium
• to describe the data transmission modes
• to demonstrate how network performance calculated

Definition of Data Communication

The Collection and distribution of the electronic representation of information FROM and TO remote facilities by means of electrical transmission system such as telephone lines, satellites or coaxial

cable.

Telephone lines

Satellites

Coaxial Cable

Raw Data/Information = must be DIGITIZED

Examples of raw data: data, text, voice, still pictures, graphics & Video

Types of Signal

* All this type of information needs to be converted into signal that can be understood by the communication media in order to transmit the data (text,picture).

Analogue Signal

- formed by continuously varying voltage levels that create a wave that can be grasped by an analogue transmitter like microphone.

- features: FREQUENCY and AMPLITUDE.

- symbolic of human voice.

Terms

Frequency: a number of completed wave's cycles. measured in Hertz (Hz) which is cycle per sec.

Amplitude: the wave's height measured in Volt (V) or decibel (dB). strong signal will create higher amplitude.

* Analogue signal is transmit through PSTN line (phone line)

Digital Signal

- transmission of binary electrical/light pulses that only have to possible states 0 and 1(language of computers:represent of square wave)

- need to be changed into analogue signal to be transmitted through PSTN line.

The process of changing

ANALOGUE to DIGITAL signal = Modulation

DIGITAL to ANALOGUE signal = Demodulation

Hardware included = MoDem

BINARY DIGITAL

Bit are the basic/smallest unit of measurement in digital which only consist of value of either 0 and 1.

1 byte = 8 bit

1 kilobytes = 1000 bytes

1 megabytes = 1000 kilobytes

1 gigabytes = 1000 megabytes

1 terabytes = 1000 gigabytes

Data Transmission Mode

Parallel transmission: a group of its bits is transmitted simultaneously by using a separate line for each bit.

Serial transmission: transmits all the bits one after another on a single line. This style is a bit slower compared to parallel.

Serial: Synchronous Transmission

- a large group of data is transmitted in blocks called a FRAME.

Serial: Asynchronous Transmission

- bits are divided into small groups (bytes) ans send independently.

- a group of bits can be sent at any time and receiver never knows when they will arrive.

DATA FLOW

message source: transmitter

destination: receiver

3 operation styles:

1) Simplex

- data/information is transmitted in ONE direction only.

- the role of transmitter and the receiver are FIXED.

Example: a radio station is a simplex channel because it always transmits the signal to its listeners and never allows transmitting back.

2) Half- Duplex

- message can flow in 2 directions but NEVER at the same time.

- one station transmits info to another without any interruption.

- the other station will response after that transmission has been completed.

- both station now can exchange its role between transmitter and receiver.

example: walkies- talkie

3) Full Duplex

- both station can transmit and receive simultaneously.

- it consists of two simplex channel.

example: phone call and online chatting.

My opinion:

There are many terms in this topic (data communication). Sometimes,people especially young generations are already know the process and the techniques on how to use certain application using computer. This is because they are exposed to the usage of computer. However, the problem is that they are not familiar with the terms related to the process or techniques used. That is why sometimes they are confused with these terms for example simplex, half-duplex and full-duplex. Other than that, I am excited to know all these terms since there are related to my daily activities such as making phone calls, online chatting and listening to radio. Now I know why we can response to each other when make phone call. At the same time, I gain knowledge that will benefit me in he future.

That is all for today's lesson. I'll continue next week.

Day 1- Wednesday, 29 February 2012

Hi Everyone.

Today is the second meeting for telecommunication and networking class. I'm glad to have Dr. Dayang as our lecturer for this subject. So far, Dr. Dayang explains on the individual assignment and also on group assignment. Regarding to the individual assignment, I need to develop a blog and that is what I'm doing right now. As for group assignment, I need to prepare a critical analysis report of networking setup of a school or organisation.

Week 1( notes)

Introduction To Telecommunications

What is communication?

The imparting, conveying or exchange of thoughts, messages,ideas, knowledge or information by sign and sounds like speech, signals, writing or behavior.

What is Telecommunications?

Communication over a long distance. (Tele = Far off)

Telecommunications refers to the transfer of data, communications from a transmitter to a receiver across a distance.

However, there are six important elements of communication technology:

1. People
2. Procedure
3. Data or Information
4. Hardware
5. Software
6. Communication or Connectivity

My opinion:

It is not a deny that communication is very important for example in an organisation. Dr. Dayang already gave a few examples and explained on certain issues regarding to this matter. In addition, the developing in technology and networking create bigger challenges to the young generation to place themselves in these areas. It is depending on individuals on how they want to develop or gain knowledge in these areas since the facilities are not becoming the main problem anymore. As for me, it is good to have an extra knowledge on technologies and networking since I am a teacher-to-be. InsyAllah. It will benefit me in the future especially on how to conduct my class. That is all for today's class.