7. Analog Data
• Analog data refers to information
which is continuous.
• For Example, an Analog clock which
is having hour, minute, and second
hands that gives information in a
continuous form; the movement of
the hands are continuous.
8. Digital Data
• Digital data refers to information
which has discrete states.
• For Example, a digital clock which
reports the hours and minutes that
will change suddenly from 10:05 to
10:06.
10. Analog Signal
• Analog signals have infinitely so many
levels of intensity over a period of
time.
• When the wave moves from value A
to value B, it passes through and it
• includes an infinite number of values
along its path.
11. Digital Signal
• Digital signals can have only a
limited number of defined values.
• Although each value can be any
number, it is often as simple as 0
or 1.
12. Speed
• This is the most generic performance term
used in networking. As such, it can mean
just about anything.
• Most commonly, however, it refers to the
rated or nominal speed of a particular
networking technology. For example, Fast
Ethernet has a nominal speed of 100
megabits per second; it is for that reason
often called 100 Mbit Ethernet.
13. Bandwidth
• Bandwidth is a widely-used term
that usually refers to the data-
carrying capacity of a network or
data transmission medium.
• It indicates the maximum amount of
data that can pass from one point to
another in a unit of time.
14. User 1 User 2
Bandwidth
Bandwidth
transmission medium
15. Frequency
• It is the number of waves that pass a
point per unit time.
Wavelength
• It is the distance between identical
points on consecutive waves.
Speed = Frequency * Wavelength
19. Cable
• Cable technology uses a coaxial cable to
deliver internet and TV service.
• coax cables work by allowing an electrical
signal to travel through the copper part of the
cable.
• When the signal reaches your home, a
modem takes the electrical signal and turns it
into a digital format that can be understood
by your devices.
20. DSL
• Digital subscriber line, or DSL for
short, is the most popular
technology in the world for
delivering digital data.
• DSL transmits an internet signal
through regular phone lines.
21. • DSL uses existing copper phone
lines to transmit internet and TV
signals.
• A copper phone line is like a
highway with four lanes.
• The voice we use in our phone
conversations only travels
through the right lane.
22.
23.
24. Types of DSL
• Asymmetric DSL (download speed is
faster than upload speed usually uses
in homes).
• Symmetric DSL (download speed is
equal to upload speed usually uses in
business).
• Very high bitrate DSL (fastest Type
And it is 3 times faster than ADSL)
25.
26. Fiber Optics
• Fiber optics uses light, rather than
an electrical signal, to transmit data
along thin glass that are bundled
together into a cable.
• This means that information can
travel at close to the speed of light.
27. Basis Fiber DSL and cable:
Signal speed &
strength
The signal keeps its
strength across long
distances
The signal gets weaker
the farther it gets from
the source.
Bandwidth
You don’t have to
worry about your
neighbors slowing
down your connection
because there are lots
of lanes on the fiber
highway, and plenty of
bandwidth to go
around.
These technologies
don’t necessarily have
a dedicated line.
This means that you
share bandwidth with
your neighbors, so
internet can be slower
or faster depending on
how much bandwidth
the people who live
near you are using.
28. Multiplexing
• It is the sharing of a medium or
bandwidth.
• It is the process in which multiple signals
coming from multiple sources are
combined and transmitted over a single
communication/physical line.
29.
30. Types of Multiplexing
• Frequency Division Multiplexing(FDM).
• Time-Division Multiplexing (TDM).
• Wavelength Division Multiplexing(WDM).
31. Frequency Division Multiplexing
• Frequency division multiplexing is
defined as a type of multiplexing
where the bandwidth of a single
physical medium is divided into a
number of smaller, independent
frequency channels.
32.
33. Time-Division Multiplexing
• Time-division multiplexing is defined as a type of
multiplexing wherein FDM, instead of sharing a
portion of the bandwidth in the form of
channels, in TDM, time is shared.
• Each connection occupies a portion of time in
the link.
34.
35. Wavelength Division Multiplexing
• Wavelength Division Multiplexing is used on fiber
optics to increase the capacity of a single fiber. It
is an analog multiplexing technique.
• Optical signals from the different sources are
combined to form a wider band of light with the
help of multiplexers.
• At the receiving end, the demultiplexer separates
the signals to transmit them to their respective
destinations.
38. Define the terms:
Signal.
Speed.
Bandwidth.
Frequency.
Wavelength.
Multiplexing in physical layer.
What are the types of signal with explanation?
Mention 3 common transmission mediums with explanation?
What are the types of DSL with explanation?
Mention two differences between fiber optic and DSL/Cable?
What are the types of multiplexing in physical layer with
explanation?
