Saturday 31 March 2012

Next

          



Hahahahaha..
We meet again..huhuhuhu...
As for today entry I will talk about PROTOCOL AND CABLING.




PROTOCOL--------> can be defined as a set of rules that governs the communications between computers on a network.

COMMUNICATION PROTOCOL-----> standards that specifically address how the devices on a network communicate.




ETHERNET = Most widely used wired networks protocol.
LOCAL TALK = a network protocol that was developed Macintosh computers.
TOKEN RING = Involve token- passing
FDDI (FIBRE DISTRIBUTED DATA INTERFACE) = A network protocol that is used primarily to
                                                                                      interconnect two or more local area networks, often
                                                                                      over large distance.





CABLE------> The medium through which information usually moves from one network device to another.


TYPE OF CABLE...


TWISTED PAIR CABLE
Twisted pair cabling is a form of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of canceling out electromagnetic interference(EMI) from external sources. 
This type of cable is used for home and corporate Ethernet networks. 
Twisted pair cables consist of two insulated copper wires 
There are two types of twisted pair cables : Shielded and Unshielded




Unshielded


Shielded







OPTICAL FIBRE CABLE
An 'optical fiber cable' is a cable containing one or more optical fibers
The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. 
It carries light impulses. It is expensive but have higher bandwidth and transmit data over longer distance.
  


COAXIAL CABLE

Coaxial lines confine the electromagnetic wave to the area inside the cable, between the center conductor and the shield. 
The transmission of energy in the line occurs totally through the dielectric inside the cable between the conductors. 
Coaxial lines can therefore be bent and twisted (subject to limits) without negative effects, and they can be strapped to conductive supports without inducing unwanted currents in them.
The most common use for coaxial cables is for television and other signals with bandwidth of multiple megahertz.
 Although in most homes coaxial cables have been installed for transmission of TVsignals, new technologies (such as the ITU-T G.hn standard) open the possibility of using home coaxial cable for high-speed home networking applications (Ethernet over coax). nithin
In the 20th century they carried long distance telephone connections.
  


PATCH CABLE
patch cable is an electrical or optical cable, used to connect one electronic or optical device to another for signal routing. 
Devices of different types (ie: a switch connected to a computer, or switch to router) are connected with patch cords, and it works. It is a very fast connection speed. 
Patch cords are usually produced in many different colors so as to be easily distinguishable,and are relatively short, perhaps no longer than two metres.
 

 Here is a video that will help you...........^^

http://www.youtube.com/watch?v=601x64peZtU&feature=related




           

new entry


Today I would like to share with all of you about NETWORK EQUIPMENT..!!
Network equipment consists of FILE SERVER, WORKSTATIONS, NETWORK INTERFACE CARD (NIC), BRIDGES, HUB AND SWITCH, ROUTER AND REPEATER.


First: FILE SERVER-----> stands at the heart of most networks.
                                           very fast computer and large amount of RAM and storage space.


WORKSTATION-------> User computer that is connected to a network.
                                          Almost any computer can serve as a network stations.




NETWORKING INTERFACE CARD-------> Provide the physical connection
                                                                                                           between the network and
                                                                                                           the computer.
                                                                                                           Major factor in determining the speed
                                                                                                           and the performance  of a network.
                                             
 3 Most common network interface------>

ETHERNET CARDS


 
LOCAL TALK CONNECTOR 
       


TOKEN RING CARD.






BRIDGE--------> Monitors the information traffic on both sides of the network so that it can pass packets of
                             information to the current location.
                             Manage the traffic to maintain optimum performance on both sides of the network.



ROUTER------->Select the best path to route a message, based on the destination address and origin.
                            Redirect data around those sections until they clear up.
                            Direct signal traffic efficiently.




REPEATER------> To boost the signal with a device.
                               Electrically amplifies the signal it receives and rebroadcast it.
                              Can be separate devices or they can be incorporated.



HUB-----> Transmit all data received to all node connected to the hub.



SWITCH-----> Identifies the device on the network for which the data is intended and sends the data to
                                 that node only.
                                Can connect Ethernet, Token ring, Fibre and other packet switched network.



GATEWAY-----> A network node equipped for interfacing with another network that uses different
                             protocols.
                             A protocol translation or mapping gateway interconnects network with different network
                             protocol technologies by performing the required protocol conversions.






here are the video to make all the things more vividly......^^

http://www.youtube.com/watch?v=72HBsTIFAaY


http://www.youtube.com/watch?v=9Axuo8TtWO8&feature=related




                                   

Friday 9 March 2012

here we go again ~~~ ^^

Here we go again....
For this class, we had learned the uses of COMPUTER NETWORKS
These are the uses:
·        Sharing a printer or internet connections among several users.
·        Sharing application software with network license, which is cheaper installed and updated on one computer only.
·        Working collaboratively, sharing database, or using collaboration tools to create and review documents.
·        Exchanging files among the network users and over the internet.
·        Connecting home computers and the entertainment devices (TV, gaming consoles, stereo systems) located within home.

Next we learn about NETWORK TOPOLOGY
 THE PHYSICAL TOPOLOGY of a network is determined by the capabilities of the network access devices and media, the level of control or fault tolerance desired, and the cost associated with cabling or telecommunications circuits
THE LOGICAL TOPOLOGY, in contrast, is the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices.




bus network topology
star network topology
ring network topology
fully connected mesh topology
partially connected mesh topology
tree network topology



anyeong~~~

Hye there....
This is my second entry in my simple and ordinary blog.
For the second class in telecommunication and networking class, Sir Razak told us about DATA TRANSFORMATION. Data transformation is data travel over a network in various characteristics, types, direction, timing and form. It consists of two signals which is ANALOG SIGNAL.-------à uses signals that are continues and exact replicas of a sound wave or image.


DIGITAL SIGNAL------à converted into binary code (1,0)


Then it also consists of
PARALLEL and SERIAL transmission like a circuit.


      


TRANSMISSIONS       : SYNCHRONOUSà organised into blocks or
groups and transferred at a regular specified
interval.

                                                                  : ASYNCHRONOUSà the process where
transmitted data is encoded with start and stop
bits, specifying the beginning and  end each of
the character ( every datas have their own ID)
                                                                  : ISOCHRONOUSàdata is sent at the same time as
types of real time applications.
Other than that, data transmissions also have three directions underneath which are SIMPLEX, HALF DUPLEX, FULL DUPLEX.