Network design - Topology

Network Design

Topology

Objective

• Given instructions, the learner will design a computer network topology with 85% accuracy.

Topology

• The physical layout of the network devices and cabling and how all the components communicate with each other.

• The basic four types of computer network topologies:

– Mesh

– Bus

– Ring

– Star

Mesh Topology

• Also call Point-to-Point Topology

• Each device is connected directly to all other devices on the network.

• A mesh topology provides Fault Tolerance, or the ability to overcome a failure.

• The fault tolerance allows the network to continue functioning in the event of a cable failure.

• Commonly used by WAN

Bus Topology

• Bus topology is a common type of Multipoint Topology

• Sharing is the key to multipoint topology.

• A computer network bus topology is characterized by one starting point and one ending point.

Parts of Bus Topology

• Segment– A single cable that runs the length

of computer network.

• Terminator– A device that absorb signal in a

bus topology. Located at each end of the cable

– The bus cannot function without the terminator.

• Packet-sniffing– Special software that views all of

the packets as they pass by on a network.

– It all allows network administrators to monitor network traffic and identify problems.

Bus Topology

Advantages

• It is simple and reliable.

• It requires a small amount of cable.

• Adding more devices to the network is easy to do.

Disadvantages

• Troubleshooting problems is difficult to do.

• It becomes slower as more devices are added to the network.

• A cable problem can shutdown the entire network.

Ring Topology

• A multipoint topology is the opposite of a bus.

• The bus has two end point, however, a ring is a circle with no end points.

Ring Topology

Advantages

• It is the easiest topology to manage and troubleshoot.

• Adding additional devices is easy to do.

• One malfunctioning computer or cable doesn’t stop the entire network.

Disadvantages

• If the hub fails, the entire network stops.

• It requires more cable.

• Cable installation can be more difficult.

Star Network

• A multipoint star topology gets it name from the fact that it resembles a star when viewed from above.

• The central device is known as a Hub.

• The hub is responsible for receiving and forwarding the packets to the other devices on the network.

Star Topology

Advantages

• It is the easiest topology to manage and troubleshoot.

• Adding additional devices is easy to do.

• One malfunctioning computer or cable doesn’t stop the entire network.

Disadvantages

• If the hub fails, the entire network stops.

• It requires more cable.

• Cable installation can be more difficult.

Hybrids Topology

• Variations of standard topology

Star Bus Topology

• Typically used to connect multiple hubs in star topologies with a bus topology

Star-Ring Topology

• Is wired liked a star but functions like a ring.

Star-Wired Ring Topology

• A topology that is wired like a star but functions like a ring.

Network Design Activity

• Use the internet to research a office, computer lab, library, call center, etc. layout to create a topology layout using the Paint application on your computer. As seen in the example below created by your instructor.