transmission media in physical layer.ppt

Transmission media in physical layer deals with the Guided media, which are those that provide a conduit from one device to another, include twisted-pair cable, coaxial cable, and fiber-optic cable.
Unguided media transport electromagnetic waves without using a physical conductor. This type of communication is often referred to as wireless communication.
Radio waves are used for multicast communications, such as radio and television, and paging systems.
Microwaves are used for unicast communication such as cellular telephones, satellite networks,�and wireless LANs.
Infrared signals can be used for short-range communication in a closed area using line-of-sight propagation.
Define Transmission Media. [2]
List the applications of guided and unguided media. [6]
What is the principle of refraction? Write a short note on Fiber optics. Clearly state its types, advantages and disadvantages. [6]
Provide the classification of Transmission media. Explain in detail each one of them. [10]
Explain physical description and application of Microwave, Broadcast Radio and Fiber optics. [10]
Explain the types of guided and unguided media with suitable diagrams. [10]
Discuss in detail about the physical description, application and transmission characteristics of the guided Media. [10]
It is very useful that a task is begun before the previous task has ended.This is known as pipelining.

There is no pipelining in Stop-and-Wait ARQ because we need to wait for a frame to reach the destination and be acknowledged before the next frame can be sent.

Pipelining does apply to other two Noisy channel protocols:
Several frames can be sent before we receive news about the previous frames.
Pipelining improves the efficiency of the transmission.
To improve the efficiency of transmission, multiple frames must be in transition while waiting for acknowledgment.

We want to keep the channel busy while the sender is waiting for acknowledgment.

In Go-Back-N ARQ protocol:

We can send several frames before receiving acknowledgments.

We keep a copy of these frames until the acknowledgments arrive.
Frames from a sender station are numbered sequentially.
As we need to include the sequence number of each frame in the header, we need to set a limit.
If the header of the frame allows m bits for the sequence number, the sequence numbers range from 0 to 2m - 1.
For example, if m is 4, the only sequence numbers are 0 through 15 inclusive.
We can repeat the sequence. So the sequence numbers are:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...
In other words, the sequence numbers are modulo-2m.
Sliding window defines the range of sequence numbers.

The sender and receiver need to deal with only part of the possible sequence numbers:

The range which is the concern of the sender is called the send sliding window.

The range that is the concern of the receiver is called the receive sliding window.
Send sliding window
Send window is an

1. 7.1
Chapter 7
Transmission Media
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. 7.2
Figure 7.1 Transmission medium and physical layer

3. 7.3
Figure 7.2 Classes of transmission media

4. 7.4
7-1 GUIDED MEDIA7-1 GUIDED MEDIA
Guided media, which are those that provide a conduit Guided media, which are those that provide a conduit
from one device to another, include twisted-pair cable, from one device to another, include twisted-pair cable,
coaxial cable, and fiber-optic cable.coaxial cable, and fiber-optic cable.
Twisted-Pair Cable
Coaxial Cable
Fiber-Optic Cable
Topics discussed in this section:Topics discussed in this section:

5. 7.5
Figure 7.3 Twisted-pair cable

6. 7.6
Figure 7.4 UTP and STP cables

7. 7.7
Table 7.1 Categories of unshielded twisted-pair cables

8. 7.8
Figure 7.5 UTP connector

9. 7.9
Figure 7.6 UTP performance

10. 7.10
Figure 7.7 Coaxial cable

11. 7.11
Table 7.2 Categories of coaxial cables

12. 7.12
Figure 7.8 BNC connectors

13. 7.13
Figure 7.9 Coaxial cable performance

14. 7.14
Figure 7.10 Bending of light ray

15. 7.15
Figure 7.11 Optical fiber

16. 7.16
Figure 7.12 Propagation modes

17. 7.17
Figure 7.13 Modes

18. 7.18
Table 7.3 Fiber types

19. 7.19
Figure 7.14 Fiber construction

20. 7.20
Figure 7.15 Fiber-optic cable connectors

21. 7.21
Figure 7.16 Optical fiber performance

22. 7.22
7-2 UNGUIDED MEDIA: WIRELESS7-2 UNGUIDED MEDIA: WIRELESS
Unguided media transport electromagnetic waves Unguided media transport electromagnetic waves
without using a physical conductor. This type of without using a physical conductor. This type of
communication is often referred to as wireless communication is often referred to as wireless
communication.communication.
Radio Waves
Microwaves
Infrared
Topics discussed in this section:Topics discussed in this section:

23. 7.23
Figure 7.17 Electromagnetic spectrum for wireless communication

24. 7.24
Figure 7.18 Propagation methods

25. 7.25
Table 7.4 Bands

26. 7.26
Figure 7.19 Wireless transmission waves

27. 7.27
Figure 7.20 Omnidirectional antenna

28. 7.28
Radio waves are used for multicast
communications, such as radio and
television, and paging systems.
Note

29. 7.29
Figure 7.21 Unidirectional antennas

30. 7.30
Microwaves are used for unicast
communication such as cellular
telephones, satellite networks,
and wireless LANs.
Note

31. 7.31
Infrared signals can be used for short-
range communication in a closed area
using line-of-sight propagation.
Note

32. Questions

Define Transmission Media. [2]

List the applications of guided and unguided media. [6]

What is the principle of refraction? Write a short note on
Fiber optics. Clearly state its types, advantages and
disadvantages. [6]

Provide the classification of Transmission media. Explain
in detail each one of them. [10]

Explain physical description and application of Microwave,
Broadcast Radio and Fiber optics. [10]

Explain the types of guided and unguided media with
suitable diagrams. [10]

Discuss in detail about the physical description,
application and transmission characteristics of the guided
Media. [10]
7.32

33. THANK YOU.
Solve these questions before moving forward.
5.33