Difference between Full Duplex, Half Duplex and Simplex tutorials





Can send and receive data at the same time


Data is send in one direction only and can never return to the source over the same link.

Collision free

CSMA/CD is susceptible to collisions


Point to Point connection only

Multi Point attachment

For e.g. Satellite TV downlink

Uses a dedicated Switch port with separate circuits

Can connect with both half and full duplex device


Efficiency is rated at 100% in both direction

Efficiency is rated at 50% to 60%

100% efficiency in one direction.

Both the end must be configured to run at full duplex mode

The duplex setting must match on device sharing a segment

Not used in internetworking.


  • MEDIA OF TRANSMISSION The way data is transmitted, following are 2 methods

WIRE Transmission

WIRE-LESS Transmission

Copper cable


1) Co-axial cable

used commonly by TV cable operator. In IT industry we use RG-58 coaxial cable.

Speed is 10 Mbps

Used in Bus Topology



2) Twisted Pair Cable

used commonly by PSTN [Public Switch Telephone Network]

speed 28.8 kbps up-to

2 mbps



3) UTP [Unshilded Twisted Pair]

used by computer IT industry and referred as CAT 3, CAT 5 cables

CAT 3 speed 10 Mbps

CAT 5 speed 100 Mbps

Fiber Optic


is constructed with center core of Silica, extruded glass or plastic. It is designed to pass specific type of light wave over long distance.

The center of multimode fiber optic has diameter of 125 micron and is appox. the size of two human hairs.



1) Infrared communication that occur in one direction can travel upto 16 Mbps & communication that travel in many directions can go up-to 1 Mbps.

Distance = 30 meters

Speed = 1 to 16 Mbps


2) Terrestrial Microwave can take place over distance from 1 to 50 miles providing there is a direct line of sight.

Distance up-to 50 miles

Speed :- 1 to 10 Mbps


3) Satellite Microwave covers virtually unlimited distance but extremely costly.


Distance upto 10000 mile

Speed :- 1 to 10 Mbps


4) Wifi The 802.11 family consist of a series of half-duplex over-the-air modulation techniques that use the same basic protocol. The most popular are those defined by the 802.11b and 802.11g protocols

Speed 1 to 7000 Mbps