Star Topology
Star Topology
 Star Networks are one of the most common
network topologies.
 consists of one central switch, hub or computer,
which acts as a conduit to transmit messages.
 reduces the chance of network failure by
connecting all of the systems to a central node.
Star Topology
Advantages
 Better performance
 Isolation of devices
 Benefits from centralization
 Easy to detect faults and to remove parts.
Star Topology
Disadvantages
 High dependence of the system on the functioning of the
central hub
 Failure of the central hub renders the network inoperable
Bus Topology
Bus Topology
 In Bus topology, all the nodes (computers as well
as servers) are connected to the single cable by the
help of interface connectors.
 Central cable is the backbone of the network.
 Every workstation communicates with the other
device through this Bus.
Bus Topology
Advantages
 Failure of one of the station does not affect others.
 Good compromise over the other two topologies as it allows
relatively high rate of data transmittion.
 Well suited for temporary networks that must be set up in a
hurry.
 Easy to implement and extend.
Bus Topology
Disadvantages
 Does not cope well with heavy traffic rates
 Difficult to administer/troubleshoot.
 Limited cable length and number of stations.
 A cable brake can disable the entire network; no
redundancy.
 Maintenance cost may be higher in the long run.
Mesh Topology
Mesh Topology
 Mesh topologies are important for large-scale peer-to-
peer systems that use low-power transceivers.
 Every computer that has to be connected to the
network is connected to every computer that is
available in the network.
Mesh Topology
 Mesh topology is best when the network setup is
required to be active 24 x 7.
 Slightly complicated as compared to other network
topologies.
 concept of mesh topology is implemented while
configuring Routers in production environments.
Tree Topology
Tree Topology
Advantages
 It is most suitable for large networks where ring and star topologies
are not efficient.
 Since it divides the network in sub-parts, so it becomes more
manageable
 There is no hassle in either expanding or removing the nodes.
 For individual segments there is dedicated line wiring to the local
hub.
Tree Topology
Disadvantages
 The network is vulnerable as it is wholly dependent
on the central hub.
 If the network becomes extremely large it becomes
difficult to manage.
Ring Topology
Ring Topology
Logical ring
 Meaning that data travels in circular fashion from one computer
to another on the network.
 Typically FDDI, SONET or Token Ring technology are used to
implement a ring network.
 Ring networks are most commonly wired in a star configuration.
 Token Ring has multi-station access unit (MSAU),equivalent to
hub or switch. MSAU performs the token circulation internally.
Ring Topology
Advantages
Disadvantages
Ring networks are moderately easy to
install.
A single break in the cable can disrupt
the
entire network.
Cable faults are easily located, making
troubleshooting easier.
A single break in the cable can disrupt
the
entire network.
Hybrid Topology
Hybrid Topology
 It is a mixture of two or more different topologies.
 Combination of topologies is done according to the
requirements of the organization.
 e.g. Star-Ring, Star-Bus topology etc.
Hybrid Topology
Advantages
Disadvantages
Reliable
Complexity of Design
Scalable
Costly Hub
Flexible
Costly Infrastructure
Effective
Networking Devices- Hub
Hub
 A hub joins multiple computers form a single network
segment.
 It is a Layer 1 devices in the OSI model.
 A hub simply receives incoming packets, possibly
amplifies the electrical signal, and broadcasts these
packets out to all devices on the network.
 They do not read any of the data passing through them
and are not aware of their source or destination
Hub
Three different types of hubs exist
 Passive
 Active
 Intelligent
Switch
The term commonly refers to a multi-port network
bridge that processes and routes data at the data link layer
(layer -2) of the OSI model.
Switch
 Switch Connects network segments or network
devices.
 Switch receives a message from any device connected
to it and then transmits the message only to the device
for which the message was meant.
 It is more intelligent device than a hub.
 Switches are sometimes called “multi-port
bridges”.
Router
A router is a device that forwards data packets between
computer networks, creating an overlay internetwork.
Router
 It uses Routing table or Routing policies to direct the
packets to its destination.
 Access routers
 Distribution routers
 Security issues with routers
Bridge
• A bridge device filters data traffic at a network boundary.
• Bridges reduce the amount of traffic on a LAN by
dividing it into two segments.
Bridge
 Operate at the data link layer.
 Inspect incoming traffic and decide whether to
forward or discard it.
Bridge
Advantages
 Simple bridges are inexpensive.
 Simple configuration modes.
 Isolate collision domains with micro-segmentation.
 It increase network length.
 Access control and network management capabilities.
 Bandwidth scales as network grows.
Bridge
Disadvantages
 Does not limit the scope of broadcast.
 Does not scale to extremely large networks.
 Extremely large networks cannot rely on bridges.
 Buffering and processing introduces delays.
Conclusion
In today’s world people want their
information to be shared, sent and received
quickly. Such network topologies and
devices make it real and possible for us.
Thank You !!!