Resources » Articles/Knowledge Sharing » Computer & Technology

Guided Transmission Media


Posted Date: 15-May-2010  Last Updated:   Category: Computer & Technology    
Author: Member Level: Gold    Points: 25


These cables are necessary for transmission of information.



Introduction:
The guided transmission media includes cables/wires to transmit the information from source to destination. The wire may be made up of copper or other metal or may be of glass/fiber. It includes electrical and light signals to flow in these wires. But these cables are very sensitive to noise and this degrades the signal also called as attenuation. There are three types of guided media transmission cables.

I. Twisted Pair Cables:
It has two copper wires and twisted with one another to form a helical structure. It is twisted because to lower the attenuation and crosstalk from the noise. Cross talk is also known as bleeding of signals. It is common wire used in telephone lines.

Advantages :
1. It is simple and flexible.
2. It is easy to install and maintain.
3. Lower in weight and inexpensive.

Disadvantages :
1. It possesses high attenuation, so we have to use repeater for long distances.
2. It has low bandwidth, so we can't use broadband applications.
3. Maximum data rate is of 1 Mbps, which is quite lower.

Types :
i. UTP (Unshielded twisted pair) : It doesn't have any metal shield over the two twisted pair cables. It maximum distance is 100 meters for signals transmission.
ii. STP (Shielded twisted pair) : It has metal shield over the two twisted pair cables. It offers protection from interference and crosstalk.



II. Co-axial Cable :
This cable consists of a solid wire core and it is surrounded by one or more wire shield (fishnet), these are separated by a plastic insulator. The inner core carries signals and shield provides the ground and protect from electro-magnetic interference. It is used in cable-TV.

Advantages :
1. It offers higher bandwidth upto 400 MBPS
2. Transmission is better than twisted pair cable.
3. We can have several channels (frequencies) through one cable, simultaneously.

Disadvantages :
1. Expensive as compared to twisted pair.
2. Not compatible with any other cable.
3. Only one use in cable TV.

Types:
i. Thick net: The thick net coaxial cable segments can up to 500 meters ling.
ii. Thin net: The thin net coaxial cable segments up to 185 meters long.



III. Optical Fiber :
These cables are made up of glass or plastic fibers. Its sources are LED or laser diodes. It uses light beam to transmit the signals. Firstly, the signal converted in to light signal from electrical signal. It has core and cladding, core is under the cladding. The refractive index of cladding is lower than that of core.

Advantages :
1. It is immune to electro-magnetic interference, as it used light signals.
2. It is suitable in all types of environment.
3. It guarantees the secure transmission of information.

Disadvantages :
1. It is quite tough to install the equipment of optical fibers.
2. It is expensive.
3. Connection losses are common problems in optical fiber.

Types :
i. Single node: It supports the segment length of up to 2 kilometers.
ii. Multi node: It supports the segment length of up to 100 kilometers.

Conclusion:
The network also depends on these cable may be the network is wireless. These cables have electrical currents and lights to transmit the data from source to destination. These are like post man.


Thanks for reading!
Related Resources:


Read related articles: Computer networks    Communication systems    Visual media admissions 2010    

Did you like this resource? Share it with your friends and show your love!




Responses to "Guided Transmission Media"

No responses found. Be the first to respond...

Feedbacks      

Post Comment:




  • Do not include your name, "with regards" etc in the comment. Write detailed comment, relevant to the topic.
  • No HTML formatting and links to other web sites are allowed.
  • This is a strictly moderated site. Absolutely no spam allowed.
  • Name:   Sign In to fill automatically.
    Email: (Will not be published, but required to validate comment)



    Type the numbers and letters shown on the left.


    Submit Article     Return to Article Index

    Awards & Gifts
    Active Members
    TodayLast 7 Daysmore...

    ISC Technologies, Kochi - India. Copyright © All Rights Reserved.