The document discusses the five main components of data communication - the message, sender, receiver, transmission medium, and protocol - and then describes different types of physical network topologies including mesh, star, bus, ring, and hybrid topologies. It provides details on each topology type, such as mesh networks using full or partial connections between all nodes, star topologies with all nodes connecting to a central switch, and bus topologies using a single cable backbone with terminators on each end.

1. Name: Istiaque AhmedName: Istiaque Ahmed
ShuvoShuvo
Id: 141311057Id: 141311057
55thth
batch, 7batch, 7thth
SemesterSemester
Sec-BSec-B
Dept. Of CseDept. Of Cse
Varendra University,Varendra University,
RajshahiRajshahi
Submitted To
Name:Name: Arifa FerdousiArifa Ferdousi
Assistant Professor,Assistant Professor,
Dept. of CSEDept. of CSE
Varendra University,Varendra University,
RajshahiRajshahi
Submitted By

2. Five Components of Data
Communication
• Message:
– text, number, images, audio, and video
• Sender and Receiver
– devices that send/receive data message
– Computer, workstation, telephone, TV, etc.
• Transmission medium
– Physical path thru which the message travels
• Protocol
– Set of rules governing data communications

3. Five Components of DataFive Components of Data
CommunicationCommunication

4. Data flow (simplex, half-duplex, and
full-duplex)
1.4

5. Type of Connection
• Point-to-Point
• Multipoint (multi-drop)
1.5

6. Physical Topology
• Mesh topology
• Star topology
• Bus topology
• Ring topology
• Hybrid topology
1.6

7. A mesh topology is one which all of the nodes are
directly connected with all of the other nodes.
A mesh topology is the best choice when you
require fault tolerance, however, it is very difficult
to setup and maintain.
There are two types of mesh network: full mesh
and partial mesh. A full mesh is one which every
workstation is connected to the other ones in the
network. In a partial mesh, the workstations have
at least two NICs with connections to other nodes
on the network. Mesh networks are commonly
used in WANs.
Mesh TopologyMesh Topology

8. Mesh Topology

9. Star TopologyTopology
The most popular topology for business today - the star
topology consists of all of the nodes on a network
connected to a central switch or hub. A node is a device
attached to the network - such as a computer.
Each node on the network has a cable back to the central
switch. If one cable fails to a node, only that node
(computer) is affected. You can combine several switches
or hubs to create several stars, all connected together.
The Star topology is very inexpensive to maintain versus
other topologies. 10BaseT is an example of Star topology.
Think of the star topology as a big wheel. At the center of
the wheel is a switch or hub and each spoke going out
from the center goes to a node.

10. Star TopologyStar Topology

11. Bus TopologyBus Topology
Bus topology is one which all of the devices on the network are
connected with a single cable with terminators on each end. This
single cable is often referred to as a backbone or trunk.
The typical Bus network uses coax as its cable. Coax is a cable
similar to what you use for your cable TV. Coax is also referred to
as 10Base2.
The upside to using coax is that it is inexpensive, easy to install,
and is not as susceptible to electromagnetic interference as twisted
pair cable is.
The downside for a coax network is the speed is limited to 10 Mbps
(Megabits per second) and that is an interruption occurs in the
cable, all of the nodes (workstations) on the cable will lose
connectivity. If a NIC fails or a cable is disconnected at any of the
points in the network, it will not be terminated properly so all of the
computers will lose connectivity to the network.

12. Bus TopologyBus Topology

13. Ring TopologyRing Topology
In ring topology, each host machine connects to
exactly two other machines, creating a circular
network structure. When one host tries to
communicate or send message to a host which
is not adjacent to it, the data travels through all
intermediate hosts. To connect one more host in
the existing structure, the administrator may
need only one more extra cable.
Failure of any host results in failure of the whole
ring. Thus, every connection in the ring is a point
of failure. There are methods which employ one
more backup ring.

14. Ring TopologyRing Topology

15. Hybrid Topology
A network structure whose design contains
more than one topology is said to be hybrid
topology. Hybrid topology inherits merits and
demerits of all the incorporating topologies.
The above picture represents an arbitrarily
hybrid topology. The combining topologies
may contain attributes of Star, Ring, Bus, and
Daisy-chain topologies. Most WANs are
connected by means of Dual-Ring topology
and networks connected to them are mostly
Star topology networks. Internet is the best
example of largest Hybrid topology

16. Hybrid TopologyHybrid Topology