3. COMMUNICATIONS
REQUIRES:
1. SENDING DEVICE – a device that
initiates the transfer.
2. COMMUNICATION CHANNEL –
provides the pathway over which the
message can travel from source to
destination.
4. COMMUNICATIONS
REQUIRES:
3. RECEIVING DEVICE – a device that
accept the sent material.
5. USES OF COMPUTER
COMMUNICATIONS
E-MAIL (ELECTRONIC
MAIL)
– the exchange of text
messages and
computer files via a
communications
network.
6. USES OF COMPUTER
COMMUNICATIONS
VOICE MAIL
– an answering
machine but converts
an analog voice
message into digital
form.
7. USES OF COMPUTER
COMMUNICATIONS
FAX (facsimile)
machine
- sends and receives
documents via
telephone lines
8. USES OF COMPUTER
COMMUNICATIONS
TELECOMMUTING
– allows employees to
work away from the
standard workplace and
communicate using
some communications
technology.
9. USES OF COMPUTER
COMMUNICATIONS
VIDEOCONFERENCING
– involves using video and
computer technology to
conduct a meeting between
participants at two or more
geographically separate
locations.
10. USES OF COMPUTER
COMMUNICATIONS
GROUPWARE
- is a software
application that helps
people work together
and share information
over a network.
11. USES OF COMPUTER
COMMUNICATIONS
BBS (BULLETIN
BOARD SYSTEM)
- a computer that
maintains a centralized
collection of electronic
messages.
12. USES OF COMPUTER
COMMUNICATIONS
GPS (GLOBAL
POSITIONING
SYSTEM)
– consist of earth based
• receivers that analyze
satellite signals to
determine the receiver’s
geographic location.
13. USES OF COMPUTER
COMMUNICATIONS
INTERNET
– a worldwide
collection of networks.
14. COMMUNICATIONS
CHANNEL
is the communications path between two
devices; this is composed of one or more
transmission media.
15. TRANSMISSION MEDIA
• is consists of materials or techniques
capable of carrying one or more signals,
this is composed of
– two types:
• the physical
• wireless transmission media
16. 2 TYPES OF
TRANSMISSION MEDIA
1. PHYSICAL TRANSMISSION MEDIA –
use wire, cable, and other tangible
materials to send communications
signals, these include:
17. 2 TYPES OF
TRANSMISSION MEDIA
a) TWISTED PAIR CABLE - often used in
telephone networks and LAN.
b) COAXIAL CABLE – data travels
through the copper wire.
c) FIBER-OPTIC CABLE – use light to
transmit signals.
18. 2 TYPES OF
TRANSMISSION MEDIA
2. WIRELESS TRANSMISSION MEDIA -
send communication signals through the
air or space using radio, microwave and
infrared signals, these include:
19. 2 TYPES OF
TRANSMISSION MEDIA
a) BROADCAST RADIO - for
radios/television.
b) CELLULAR RADIO - for mobile
communications/cellular telephones.
c) MICROWAVES - radio waves that
provide high speed signal transmission.
20. 2 TYPES OF
TRANSMISSION MEDIA
d) COMMUNICATIONS SATELLITE - a
space station hat receives microwave
signals from an earth based station.
e) INFRARED – sends signal using
infrared light waves.
21. TRANSMISSION
CHARACTERISTICS
transmission sent during communications
categorized in these characteristics:
1. SIGNAL TYPE
A) analog
B) digital
C) broadband
D) baseband
22. TRANSMISSION
CHARACTERISTICS
2. TRANSMISSION MODES
A) asynchronous transmission
B) synchronous transmission
23. TRANSMISSION
CHARACTERISTICS
3. TRANSMISSION DIRECTION
A) simplex transmission
B) half-duplex transmission
C) full duplex transmission
24. TRANSMISSION
CHARACTERISTICS
4. TRANSFER RATES
A) Bandwidths – range of frequencies
that a transmission can carry.
25. TELEPHONE NETWORK
the public switched telephone network (PSTN) is
the worldwide telephone system that handles
voice communication and also an integral part of
data communications, sending data via the
telephone network travel over a variety of
transmission media and can be sent using dial-
up lines or dedicated lines.
27. TELEPHONE NETWORK
DIAL-UP LINES
- dial-up line is a
temporary connection
that uses one or more
analog telephone lines
for communications.
28. TELEPHONE NETWORK
DEDICATED LINES
– connections that always
established between two
communications devices, it
provides constant connection.
Businesses can buy or leased
dedicated line from telephone or
communications Service
Company.
29. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
1. ISDN (Integrated Services Digital
Network) LINES
– is a set of communication standards for
simultaneous digital transmission of voice, video,
data, and other network services over the
traditional circuits of the public switched
telephone network.
30. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
1. ISDN (Integrated Services Digital
Network) LINES
31. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
2. DIGITAL SUBSCRIBER LINES
(DSL)
- uses broadband to transmit a greater number of
bytes on a standard twisted-pair cable.
o Some of the DSL installations can provide a dial
tone so you can use the line for both voice and
data.
32. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
2. DIGITAL SUBSCRIBER LINES (DSL)
33. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
3. T-CARRIER LINES
- is any of several types of digital lines that
carry multiple signals over a single
communications.
35. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
4. ASYNCHRONOUS TRANSFER MODE
(ATM)
- is a service designed to carry voice, data,
video, and multimedia at high speeds -
currently up to 622 Mbps.
36. 4 POPULAR TYPES OF
DIGITAL LEASED LINES
4. ASYNCHRONOUS TRANSFER MODE
(ATM)
37. COMMUNICATIONS
SOFTWARE
- that makes it possible to send and
receive data over telephone lines through
modems.
- that manage the transmission of data, instruction, and
information between computers.
- helps users establish a connection to another computer or
network.
- provide an interface for users to communicate with one
another.
39. COMMUNICATIONS
DEVICES
is any type of hardware capable of
transmitting data, instructions, and
information between a sending device and
a receiving device.
41. COMMON TYPES OF
COMMUNICATION DEVICE
MODEM
- device that perform conversion in digital
signals and analog signals, it can be
internal or external.
- Both the sending and receiving ends of a
communications channel must have a modem
for data transmission to occur.
43. COMMON TYPES OF
COMMUNICATION DEVICE
CABLE MODEM
– a modem that sends and receives data
over the cable television (CATV) network,
which consist largely of coaxial cable.
45. COMMON TYPES OF
COMMUNICATION DEVICE
MULTIPLEXER (MUX)
– a device that combines two or more input
signals from various devices into a single
stream of data and then transmits it over a
single transmission medium.
47. COMMON TYPES OF
COMMUNICATION DEVICE
• NETWORK INTERFACE CARD (NIC)
– an expansion card that you insert into an
expansion slot of a personal computer or
other device, such as a printer, enabling the
device to connect to a network.
48. COMMON TYPES OF
COMMUNICATION DEVICE
• NETWORK INTERFACE CARD (NIC)
49. CONNECTING NETWORKS
thousands of computer networks exist from
small networks to global networks, to
interconnect the many types of networks
there are many various types of
communications devices including these:
50. CONNECTING NETWORKS
HUB
– also called concentrator or multistation
access unit (MAU), provides a central point
for cables in a network, usually contain
ports for eight to twelve computers and
other devices.
60. NETWORK
collection of computers and devices
connected by communications
channels that allows users to share
data, information hardware, and
software with other users.
62. TYPES OF NETWORKS
LOCAL AREA
NETWORK (LAN)
– is a network that
connects computers
and devices in a limited
geographical area.
63. TYPES OF NETWORKS
WIRELESS LAN
(WLAN)
– is a LAN that uses no
physical wires.
64. TYPES OF NETWORKS
METROPOLITAN
AREA NETWORK
(MAN)
– connects LANS in
metropolitan area.
65. TYPES OF NETWORKS
WIDE AREA
NETWORK (WAN)
– is a network that
covers a large
geographical area.
66. NETWORK TOPOLOGY OR
NETWORK ARCHITECTURE
the configuration or physical arrangement
of the device in a communication network.
67. 3 COMMONLY USED
NETWORK TOPOLOGIES
1. BUS NETWORK
– node must be intelligent enough to listen
to the bus.
68. 3 COMMONLY USED
NETWORK TOPOLOGIES
2. RING NETWORK
– each node has an equal amount of
intelligence.
69. 3 COMMONLY USED
NETWORK TOPOLOGIES
3. STAR NETWORK
– all nodes are joined at single central point
using one link for each node.
70. PROTOCOL
is a set of rules and procedures for
exchanging information among computers.
71. PROTOCOL
ETHERNET
- is a LAN protocol that
allows personal
computers to contend
for access to a network.
72. PROTOCOL
TOKEN RING
- is protocol that control
access to a network by
requiring that a special
signal called a token is
shared or passed
among network devices.
74. INTRANETS
are internal networks that use Internet and
Web technologies, it makes company
information accessible to employees to
facilitate working in groups.
