Internet Protocol

Last lecture of telecommunication & Networking !

While being busy up and down these days... 

I realise that every good thing must come to an end.

This week, we learnt about internet protocol.

Internet protocol 

-is the internet standard protocol that provides a common later over different networks.

-Every computer has unique IP address

-IP address consists of 32 bits ( 4 octets, 0-255)

-consists of 2 parts : identifying the network, identifying the node/host

-Classes of address determines which part belongs to the network and which part belongs to the node.

-All nodes has same network prefix but unique host number.


Class A Network

-Binary add starts with 0

-Decimals can be anywhere from 1-126

-The first 8 bits identify the network, the remaining 24 indicates the nodes.

Class B Network 


-Binary add starts with 10
-Decimals can be anywhere from 128-191
-the number 127 is used for loopback and internal testing system
-The first 16 bits identify the network and the remaining 8 indicates the nodes.

Class C Network

-Binary add starst with 110

-Decimals can be anywhere from 192-223

-The first 24 bits identify the network

Class D Network

-Binary add starts with 1110

-Decimals can be anywhere from 224-239

-used for multicasting

Class E Network

-Binary add starts with 1111

-Decimals can be anywhere from 240-255

-Experimentation, never been utilized

What is ISP?

- Internet service provider.
- Organisation that provides access to the internet.

What is HTTP?

-Hypertext transfer protocol
-application protocol for distributed, collaborative, hypermedia information system.
-foundation of data communication for WWW (World Wide Web)

My little reflection of the day:

Thanks to the course, now I understand more about telecommunication & networking. Dr Dayang has been conducting a real useful rudiment. Even though it is not my core subject, it's always of no harm to learn more out of the box :)
Knowledge should not be bounded or confined. I hope that all these insights will be helpful in my future english teaching. It's an era of technology, I am convinced that english teachers must also be weaponed with ICT literacy... :)

Thank you dearest lecturer and readers ! I had a whale of a time here :)

Bluetooth Technology

We were late for  the class today, sincerely sorry to Dr.Dayang and the others who came on the dot.. Won't be habitual late comer I promise ^^

And yes, it's a new new day, we're clinging on new new branch originated from last week's topic, Wireless Technology.

WHAT IS BLUETOOTH IN DETAILS, THEN?  :P

Explaining once again, Bluetooth...

is of course not something to do with dentist XD

• is a proprietary open wireless technology 

• exchanges data over short distance, using short wavelength radio transmissions in the ISM band from 2400-2800 MHz
• Creates PANs or piconet with high levels of security.

How Bluetooth works?

•  Bluetooth networking transmits data via low-power radio waves. 
• It communicates on a frequency of 2.45 gigahertz(between 2.402 GHz and 2.480 GHz).
• Does not require a line of sight connection.
• Avoids interference  by sending out very weak signals of about 1 milliwatt. By comparison, the most powerful cell phones can transmit a signal of 3 watts. 
• The low power limits the range of a Bluetooth device to about 10 meters , reducing interference between the computer system and the portable telephone or television.
• is able to connect up to 8 devices simultaneously. 
• uses a technique called spread-spectrum frequency hopping . In this technique, a device will use 79 individual, randomly chosen frequencies within a designated range, changing from one to another on a regular basis. Also  minimizes the risk that portable phones or baby monitors will disrupt Bluetooth devices.
• This frequency is also used by the wireless networking standard IEEE 802.11 but operates with shorter data packets.
•  Once a piconet is established, the members randomly hop frequencies in unison so they stay in touch with one another and avoid other piconets that may be operating in the same room.
• Each piconet can hold up to 8 units.
• Before communication can happen, a device must request a connection either to accept or reject.
• Allows 3 types of data links between any 2 nodes--->an asynchronous data channel, many  asynchronous data channel and simultaneous voice channel.

The Pros and Cons of Bluetooth Technology

1. Advantages:

• accepted worldwide
• low implementation cost
• not easily affected by obstacles
• low power consumption
• simple and easy to use
• less interference
• standard protocol
• constantly upgrades
• perfect scenario for home network
• faster data and voice sharing
• Wireless synchronisation

2.  Disadvantages:

• more open to interception and attack.
• Infrared technology can have data rates of about 4 MBps, which delivers very fast rates for data transfer, whilst Bluetooth only has up to 2.1 MBps.
• sometimes runs slow

Bluetooth and the future

• initiates more ubiquitous usage and links with WiFi and Ultra Wideband ( UWB) broadcast technology
• Operating systems such as the Mac OS and Windows continue to have native support for Bluetooth.
• The Bluetooth SIG partners are working on enabling Bluetooth information points, to enable advertising models based around users pulling information from ‘information points’, rather than having to ‘push’ information out.
• Other emerging features include Bluetooth in cars; automatic configuration of piconets; and quality of service (QoS) improvements, for example enabling audio and video data to be transmitted at a higher quality.
• Going to be one of the major players in the wireless future

Broadband

Since I have described what broadband is on last week' s entry, let's look at something different this time :)

Infrared Red

• Infrared red light is located between the visible and microwave portions of the electromagnetic spectrum. 
•  has a range of wavelengths
• "Near infrared" light is closest in wavelength to visible light and "far infrared" is closer to the microwave region of the electromagnetic spectrum.
• Far infrared wavelengths are about the size of a pin head and the shorter, near infrared ones are the size of cells or basically microscopic.
• When an object come into range of the infrared sensor’s detection zone, the valve is activated. After the user removes their hands, the valve closes. The circuit of the Autotap resets automatically for the next user.
  
  

My little reflection of the day:

Today it eventually reached my group's turn to do class presentation. Our topic is forum and chatting. I did the part for Yahoo Messenger. Frankly speaking before I was requested to perform the task, I never had a Yahoo account. It's my very first time creating one for myself, as well as teaching others how to create one. Learning and getting to know more are the most precious values that I've been instilled by this course.

Wireless & Unbounded Media

Know what, morning class is truly challenging people's will and faith XD
Struggle almost every morning to wake up and go to class on time, and today is not any exception too. 

I'm quite convinced that even thing as difficult as waking up from sweet slumber has failed to beat me up, what more can defeat me today, right?

Fighting～

Back to the main topic ! Today we learnt about wireless and unbounded media aka unguided media.

What is wireless?

Wireless network : A telecommunication network which its interconnection between nodes is implemented without the use of wires.

Wireless communication : Involves radio frequency, microwave and infrared (IR) short range communication.

Devices commonly use wireless technology are portable computers, desktop computers, hand-held computers, PDA, cellular phones, pen-based computers and pagers.

As for pratical purposes,

1.  Mobile users can use their cellular phone to access e-mail
2. Travelers can access to internet in places like airport using portable computer
3.  Users at home can connect devices to computer to synchronize data and transfer files

Types of Wireless Network

1. Wireless Wide Area Network (WWAN)

 

2. Wireless Metropolitan Area Network (WMAN)

3. Wireless Local Area Network (WLAN)

4. Wireless Personal Area Network (WPAN) 

What is Wi-Fi?

- Wireless-fidelity

- Transmits computer data over distances using radio waves 

- Based on IEEE 802.11 specifications

-describe the underlying technology of WLAN

What is Bluetooth? 

- Industrial specification for WPAN

- A way to connect and exchange information between devices

- Licenced by Bluetooth Special Interest Group

What is Broadband ?

- Provides high speed wireless access over a wide area from devices such as personal computers and data networks.

- Having instantaneous bandwidth greater than around 1 MHz 

- Supporting data rates greater than about 1.5 Mbit/s

Cellular Systems : 0G, 1G, 2G, 3G, 4G

* 4G is 10 times faster than 3G but more expensive.

* 3G- WDMA.EVDO,HSP

* 4g- LTE, Wi Max

Unbounded Media

- Transport electromagnetic waves without physical conductor
- Signals are broadcasting through air
- Available to anyone who has a capable device

Terrestrial Microwave
- Requires line-of-sight transmission and reception requirement
- The taller the antenna, the longer the sight distance
- Signals transmit one-way
- To increase distance, a system (repeater) can be installed with antenna.

2 types of antenna:

 1. Parabolic Dish

 

 2. Horn

Satellite

- Super tall antenna & repeater

- Single bounce

- High quality communication 

- Capable of monitorning any location on earth

- Geosynchronous satellite : orbit speed is based on distance from the planet

- Mininimum 3 satellites to provide full global transmission

Transmission from earth to satellite ---> uplink

Transmission from satellite to earth ---> downlink

Radio frequency 

-a rate of electrical oscillation ranging from 3KHz to 300GHz

-corresponds to the frequency of radio waves

Cellular Phone

 - a device that can make and receive telephone calls over a radio link whilst moving around a wide geographic area

 - It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network.

My little reflection of the day:

Today,my classmates shared us the steps to create a webpage using Microsoft Office 2003.

I learnt quite a lot from the tutorial given by them, for instance, how to hiperlink on a webpage.

I feel that this course has opened a very special window for my life. I view more :)

Cabling

My dad always tells me, " You must have cable if you'd like to succeed your career."


Cable Cable, what does that mean? XD


In terms of telecommunication and networking, cabling is a medium through which information usually moves from one network device to another.




Several types of cable are commonly used with LANS. But in some cases, a network utilizes only 1 type of cable.


There are 5 types of Cable:




1.Unshielded Twisted Pair ( UTP) 

- Wires are twisted.
- 4 pairs of wires
- each pair is twisted with a different number of twists per inch 
- eliminate interference from adjacent pairs and other electrical devices

Standard connector: an RJ-45 connector 




2.Shielded Twisted Pair ( STP )

- 2 individual wires wrapped in a foil shielding
- provide more reliable data communication
- suitable for environment with electrical interference
- the extra shielding might make the cable bulky
- Often used on networks like  Token Ring Topology




3. Coaxial Cabling

- has a single copper conductor at its center
- a plastic layer provides insulation between the center conductor and a braided
  metal field.
- The metal shields help to block outside interference


-Connector : BNC connector ( available for different types of adapters)




4. Fibre optics cable

-consists of a center glass core surrounded by several layers of protective materials

- transmits light rather than electronic signals eliminating the problem of electrical interference.

-ideal for certain environments that contain a large amount of electrical interference..

- able to transmit signals over much longer distances than coaxial and twisted pair.

 

Physical Topology

Find stationary written notes boring? Click this video ^^

My little reflection of the day: 

Today my classmates shared us the baby steps of creating a blog.Very interesting. And I realise that the particulars of a blog are much more complex than what I know superficially.

I think class presentation is very immportant as it clearly points out our ignorance. :)