Network Topology

Reporter: Manolo L. Giron

LEARNING OUTCOMES

At the end of this topic, students should be able to:

1) Explain types of network topologyand wiring diagram for common topology.

What Is a Network?

A network is a collection of computers and devices connected together via

communications devices and transmission media

Network Topology

Shelly Cashman

A network topology refers to the layout of the computers and devices in a communications network.

What Is a Network Topology?

Network Topology

Shelly Cashman

Network Topology

Physical Topology

•The arrangement of a cabling is the physical topology.

Logical Topology

•The path that data travels between computers on a network is the logical topology.

It refers to both the physical and logical layout of a network.

Types of network topology.Three commonly used network topologies are:

Network Topology

Bus Network

Star Network

Ring Network

Bus Network Topology

A bus network consists of a single central cable (backbone), to which all computers and other nodes connect.

Backbone

Network Topology

Bus Network Topology The bus is the physical cable that connects the computers and other nodes.

The bus in a bus network transmit data, instructions, and information as a series of signal.

Those signals are sent as electrical pulses that travel along the length of the cable in all directions.

Network Topology

When a sending device transmits data, the address of the receiving device is included with the transmission.

If the device address does not match the intended address for the data, the device ignores the data.

If the data does match the device address, the data is accepted.

All devices receive the data but only the receiving device accept them.

Bus Network Topology

Network Topology

Bus Network Topology

Advantages:

1. Inexpensive and easy to install.

2. Computers and other nodes can be attached and detached at any point on the bus without disturbing the rest of the network.

3. Failure of one node usually does not affect the rest of the bus network.

Network Topology

Bus Network Topology

Disadvantages:

1. Because all systems on the network connect to a single cable or backbone, a break in the cable will prevent all systems from accessing the network.

2. It is difficult to identify the problem if the entire network shut down.

Network Topology

Bus Network Topology wiring diagram Use a Coaxial cable as a bus. Each nodes is connected to the single bus

cable through T-Connector. 50 ohms terminator is required at each end of the bus cable to prevent the signal from bouncing back and forth on the bus cable.

T-Connector

Terminator

Network Topology

STAR NETWORK TOPOLOGY

Network Topology

Star Network Topology

• All the computers and other nodes on the network connect to a central device, thus forming a star.• All data that transfers from one node to another

passes through the central device.• The central device takes a signal that comes from any

node and passes it along to all the other nodesin the network.

Network Topology

Star Network Topology

Advantages:

1. If one node fails, only that node is affected.

2. Nodes can be added to or removed from network with little or no disruption.

3. Easy to troubleshoot and isolate problem.

Network Topology

Star Network Topology

Disadvantages:

1. If the hub or switch fails, the entire network will be inoperable.

2. Requires more cable than most of the other topologies.

3. More expensive because of the cost of the hub/switch.

Network Topology

Star Topology wire diagram

All the computers and other nodes on thenetwork connect to a central connection point

such as, hub or switch. UTP straight through cable for every unit to

connect in central connection point. RJ 45 use as connector.

Network Topology

Hub / Switch

RING NETWORK TOPOLOGY

Network Topology

Ring Network Topology

On a ring network, a cable forms a closed loop ( ring ) with all computers and devices arranged along the ring.

Network Topology

Ring Network Topology

Data transmitted on a ring network travels from node to node around the entire ring, in one direction

Token Ring a sophisticated scheme uses a ring architecture topass data from one computer to another in one direction.

Each node takes a turn sending and receiving information through the use of a token.

Network Topology

Ring Network Topology

The token along with any data is sent from the source deviceto destination device until it comes back

around to the source device for confirmation.

Only the device with the token is allowed to send data. All other devices must wait for the token to come to them.Token circle the ring up to 10,000 times per second!

Network Topology

Ring Network Topology (the old version)

Network Topology

Ring Network TopologyAdvantages:

1. The transmission of data is relatively simple as packets travel in one direction only.

2. Cable faults are easily located, making troubleshooting easier.

3. The uses of token passing enables all nodes in a ring topology to share the network resources fairly.

Network Topology

Ring Network Topology

Disadvantages:

1. A failure in any cable or node breaks the loop and can take down the entire network.

2. Data packets must pass through every computer therefore, this makes it slower.

3. A ring network can span a larger distance than a bus network, but it is more difficult to install.

Network Topology

Ring Topology wiring Diagram (old ring topology)

Network Topology

1.Use an Network Interface Card with Bayonet Neill-Concelman (BNC)port.

2.Connect the middle BNC -T Connector to the NIC BNC port.

3.Connect two COAXIAL CABLE to the both side of BNC connector.

4.Connect all the nodes with NIC BNC, BNC-T connector and wire to form a ring.

Ring Topology wiring Diagram (old ring topology)

Network Topology

Use a Hub as a media attachment unit(MAU)

UTP Cable with RJ45 Connector use to connect the node to the MAU.

Ring Topology wiring Diagram (new ring topology)

Network Topology

Tree Network Topology

Network Topology

Variation of bus topology. Shape of the network is like a tree with

central branching and sub branching. Transmission is done in the same way as in

bus topology. Best suited for application which have

hierarchical flow of data and control. Also called hybrid topology.

Tree Network Topology

Network Topology

Advantages

1. Supported by several hardware and software venders.

Disadvantages 2. Overall length of each segment is limited by the type

of cabling used.

3. If the backbone line breaks, the entire segment goes down.

4. More difficult to configure and wire than other topologies.

Tree Network Topology

Network Topology

Mesh Network Topology

Network Topology

Each node is connected to more than one node.

Advantages1. Outstanding for long distance.2. Provide extensive back-up, rerouting and pass-

through capabilities.3. Communication is possible between any two nodes

on the network.4. Used in large internetworking environments.5. Ideal for distributed networks.

Mesh Network Topology

Network Topology

Disadvantages

1. These networks are much more difficult to install than the other topologies.

2. More expensive.

Mesh Network Topology

Network Topology

My References

CABLING The Complete Guide to Copper and Fiber-Optic Networking Fourth Edition by Andrew Oliviero and Bill Woodward

Communication And Network Concepts from www.cbsecsnip.in

INTERNET TECHNOLOGY from www.slideshare.com

Discovering Computer Fundamentals by Shelly Cashman