1. Why it is important to explore the different categories of data communication systems?
To understand the system’s functionalities, advantages, and limitations
2. helps us understand the geographical range over which these communication systems
operate. – SCOPE-BASED CATEGORIES
3. A communication within a very personal and limited space. It allows communication and
share of data in close space. – PERSONAL AREA NETWORK
4. Covers a more substantial geographic area, such as a home, office, or a campus. They
enable file sharing, printer access, and internet connectivity for all devices within the
defined area. – LOCAL AREA NETWORK
5. Spans a city or a large campus. It connects multiple LANs within a city or across a large
campus, enabling data exchange between these localized networks. They are often used
by universities, city municipalities, or large enterprises with multiple locations. –
METROPOLITAN AREA NETWORK
6. Its reach over a vast geographic area, which could be a country, continent, or even the
entire world. It connects devices and networks across the globe, enabling
communication on a global scale. – WIDE AREA NETWORK
7. In this category, we classify communication systems based on their primary purpose. –
PURPOSE-BASED CATEGORIES
8. This category encompasses communication systems primarily designed for spoken
conversations. It serves the purpose of enabling real-time, verbal interactions, making it
ideal for conversations, interviews, customer support, and emergency services. – VOICE
COMMUNICATION
9. This category revolves around the transmission of digital data, such as text, files, and
binary information. It is the backbone of the internet. It allows us to access and share
vast amounts of data globally. – DIGITAL COMMUNICATION
10. This category combines various forms of media, including text, images, audio, and video,
within a single communication channel. It enhances our ability to express ideas and
emotions. It is widely used in video conferencing, streaming services, and social media
platforms. – MULTIMEDIA COMMUNICATION
11. Classified data communication system based on the technology they use. –
TECHNOLOGY-BASED COMMUNICATION
12. These systems use physical cables to transmit data signals – WIRED COMMUNICATION
13. These systems transmit data through the airwaves using electromagnetic signals,
eliminating the need for physical cables. – WIRELESS COMMUNICATION
14. Advantages of Wired Communication – HIGH RELIABILITY, CONSTANT SPEED, SECURITY
15. Advantages of Wireless Communication – SCALABILITY, MOBILITY, CONVENIENCE
16. These systems use thin strands of glass or plastic to transmit data as pulses of light,
offering exceptional speed and reliability. – FIBER OPTIC COMMUNICATION
17. Advantages of Fiber-Optic Communication – SPEED, HIGH BANDWIDTH, IMMUNITY TO
INTERFERENCE
18. is the arrangement with which computer systems or network devices are connected to
each other – NETWORK TOPOLOGY
19. It provides a dedicated link between two devices. The entire capacity of the link is
reserved for transmission between those two devices. It is the simplest communication
between two nodes, in which one is the sender and the other one is the receiver.
POINT TO POINT
20. It is one in which more than two specific devices share a single link. This topology is
based on “sharing”. - MULTIPOINT
21. In this network, every device has a dedicated point-to-point link to every other device.
The term dedicated means that the link carries traffic only between the two devices it
connects. Total number of physical links required in this topology is n (n-1) where n
represents total number of nodes in the topology. However, if each physical link allows
communication in both directions (duplex mode), we can divide the number of links by
2. – MESH NETWORKS
22. One long cable acts as a backbone to link all the devices in a network – BUS TOPOLOGY
23. In this topology, each device has a dedicated point-to-point connection with only the
two devices on either side of it. – RING TOPOLOGY
24. A star backbone with three bus networks – HYBRID TOPOLOGY
25. is used to classify different types of computer networks based on who owns or controls
access to the network resources. These categories help define the level of accessibility
and security associated with a particular network. – OWNERSHIP BASED CATEGORIES
26. It is a network that has the least or no restrictions on it. It can be freely accessed by
anyone, without any restrictions. This type of network is publicly owned by the
government or NGOs, third-party organizations, often Internet service providers (ISPs)
or telecommunications companies. – PUBLIC NETWORK
27. It is a network in which various restrictions are imposed to secure the network, to
restrict unauthorized access. This type of network is privately owned by a single or
group of people for their personal use. Local Area Network(LAN) can be used as a
private network. – PRIVATE NETWORK
28. classify communication methods in computer networks based on how data is
transmitted between devices. – TRANSMISSION MODE BASED CATEGORIES
29. the communication is unidirectional, as on a one-way street. Only one of the two
devices on a link can transmit; the other can only receive. There is no feedback or
response from the receiver to the sender. – SIMPLEX
30. each station can both transmit and receive, but not at the same time. When one device
is sending, the other can only receive, and vice versa. – HALF-DUPLEX
31. both stations can transmit and receive simultaneously. Both sender and receiver can
transmit and receive data simultaneously without the need for a switching mechanism.
– FULL-DUPLEX
32. refers to the exchange of data or information between two or more devices or systems
using various technologies and protocols. – DATA COMMUNICATION
33. play a crucial role in data communication networks. These elements define how devices
are organized and connected, impacting the network's performance, scalability, and
fault tolerance. – CONFIGURATIONS AND NETWORK TOPOLOGIES
34. Refers to the process of assigning network settings, policies, flows, and controls. It
involves managing a network and its devices by applying the right set of policies,
controls, and configurations. – NETWORK CONFIGURATIONS
35. one or more central servers provide resources or services to multiple client devices.
Clients request services or data from servers. Commonly used in web hosting, email
servers, and database systems. Provides centralized control and security but may create
blockages if the server is overwhelmed. – CLIENT-SERVER CONFIGURATION
36. devices (peers) communicate directly with each other without a central server. Often
used for file sharing, video conferencing, and collaborative applications. Offers
decentralization but can be less secure and challenging to manage in larger networks. –
PEER TO PEER (P2P) CLIENT/SERVER NETWORK CONFIGURATION
37. The most commonly used computer networking model. The designated servers function
only as servers and are not used as a client or workstation. There can be a separate
dedicated server for each function or one single general purpose server responsible for
all services. – DEDICATED CLIENT/SERVER NETWORK CONFIGURATION
38. In the context of computer networks, this refers to the pattern or arrangement of how
devices are connected to each other within a network. - TOPOLOGY
39. It describes the layout or appearance of a network. It defines how devices are
interconnected and how data is transmitted between them. This is how the computers,
cables, and other components within a data communications network are
interconnected, both physically and logically. – NETWORK TOPOLOGY
40. defines the physical layout of the network. It describes how the devices in the network
are physically connected – PHYSICAL TOPOLOGY
41. defines the logical layout of the network. It describes how the devices in the network
communicate with each other and how data is transmitted – LOGICAL TOPOLOGY
42. uses the one-to-all method. When a device transmits a message, the message reaches
all the nodes of the same link. All nodes read the message and determine whether the
message is intended for them. – LOGICAL BUS TOPOLOGY
43. uses the one-to-one method. In this method, each node receives data only from one
node and transmits data only to one node. Data packets travel in a unidirectional
manner from one node to the next until they reach their intended destination. –
LOGICAL RING TOPOLOGY
44. creates end-to-end connections on demand. When the switch receives a data packet, it
checks the source address and destination address of the packet and creates a logical
connection between the sender node and the receiver node. When the transmission is
over, the switch terminates the logical connection. – SWITCHED LOGICAL TOPOLOGY
45. Placement of various nodes. – PHYSICAL TOPOLOGY
46. Deals with the data flow in the network. – LOGICAL TOPOLOGY
47. is multipoint. One long cable acts as a backbone to link all the devices in a network. – BUS
TOPOLOGY
48. is a connection running between the device and the main cable. - DROP LINE
49. is a connector that either splices into the main cable or punctures the sheathing of a
cable to create contact with the metallic core. – TAP LINE
50. each device has a dedicated point-to-point connection with only the two devices on
either side of it. – RING TOPOLOGY
51. each device has a dedicated point-to-point link only to a central controller, usually called
hub. – STAR TOPOLOGY
52. the nodes are connected to each other completely via a dedicated link in which the
information is travel from node to node and there are N(N-1)/2 links in this topology if
there are N nodes. – MESH TOPOLOGY
53. is a type of network topology that combines two or more network topologies. – HYBRID
TOPOLOGY
54. Broadly defined as anything that can carry information from a source to a destination
transmission. – TRANSMISSION MEDIA
55. In Data Communication, it is usually free space, metallic cable, or fiber-optic cable. TRANSMISSION MEDIUM
56. Directed and contained by the physical limits of the medium. – GUIDED MEDIA
57. Types of Guided Media: TWISTED PAIR, COAXIAL CABLE, FIBER-OPTIC
58. sends electromagnetic waves without the need of a physical medium. - UNGUIDED
TRANSMISSION/ WIRELESS TRANSMISSION
59. is the medium through which electromagnetic energy can freely travel in unguided
transmission. – AIR/FREE SPACE
60. Radio waves in this case go through the lowest part of the atmosphere, touching the
Earth. These low-frequency (below 2MHz) waves radiate from the transmitting antenna
in all directions, following the curvature of the globe. - GROUND PROPAGATION
61. Higher-frequency (below 2-30MHz) radio waves are sent into the ionosphere and
reflected back to Earth in this process. This form of transmission permits transmitting
across longer distances while using less power. - SKY PROPAGATION
62. Very high-frequency (above 30MHz) transmissions are delivered in straight lines from
antenna to antenna in this type. - LINE-OF-SIGHT PROPAGATION
63. The section of the electromagnetic spectrum defined as radio waves and microwaves is
divided into eight ranges, called BANDS, each regulated by government authorities.
64. Electromagnetic waves ranging in frequencies between 3 kHz and 1 GHz. – RADIO
WAVES
65. propagated in all directions. – OMNIDIRECTIONAL
66. Electromagnetic waves having frequencies between 1 and 300 GHz. - MICROWAVES
67. the sending and receiving antennas need to be aligned. – UNIDIRECTIONAL
68. Every line parallel to the line of symmetry (line of sight) reflects off the curve at angles
such that all the lines intersect in a common point called the focus. The parabolic dish
works as a funnel, catching a wide range of waves and directing them to a common point.
In this way, more of the signal is recovered than would be possible with a single-point
receiver. - PARABOLIC DISH ANTENNA
69. Outgoing transmissions are broadcast up a stem (resembling a handle) and deflected
outward in a series of narrow parallel beams by the curved head. Received transmissions
are collected by the scooped shape of the horn, in a manner like the parabolic dish, and
are deflected down into the stem. – HORN ANTENNA
70. Electromagnetic waves ranging in frequencies with frequencies from 300 GHz to 400 THz.
Infrared waves, having high frequencies, cannot penetrate walls. The infrared band,
almost 400 THz, has an excellent potential for data transmission. Such a wide bandwidth
can be used to transmit digital data with a very high data rate. – INFRARED WAVES