THE BEECHMONT CREST NETWORKING GUIDE:
ONLINE GUIDE TO NETWORKING / NETWORK + EXAM OBJECTIVES
Part I: Introduction to Networking
Network Topologies
Network Topologies
-Topology refers to the physical and logical layout of a network.
- Physical topology = actual layout of cables and network devices
- Logical topology = how the network interacts with the devices that use it.
Common Types of Network Topologies:
1. Linear Bus Topology
Characteristics:
-All computers on the network connected by a central trunk or backbone
-Computers connect to the trunk using T connectors
-Each end of a physical bus topology must be terminated (to avoid signal reflection)
-Most commonly implemented with the IEEE 802.3 standard
Advantages:
-Low cost
-Minimal cable requirements
-No specialized network equipment needed
Disadvantages:
-A break in the cable trunk will prevent all computers from accessing the network
-Network can be disrupted when computers added or removed
2. Ring Topology
-This topology is a logical ring. Data travels circularly around the network, from one computer to another.
-It is not a physical ring topology.
-The failure of a single computer or section of cable can bring down the entire network.
-Ring networks are usually wired as physical star configurations.
-If a Token ring network, then a multistation access unit (MSUA) circulates the token within the network.
Advantages:
-Easy to troubleshoot
-Easy to install
Disadvantages:
-A single cable break disables the network
3. Star Topology
Characteristics:
-All computers connected to central device called a hub or switch
-Each device connected to hub by a separate length of cable, creating a point-to-point connection between the device and the hub.
-Most widely used network design
Advantages:
Expansion of network will not interrupt network service
The failure of a length of cable affects only the device that is connected to it.
Troubleshooting easy
Disadvantages:
Expensive: requires more cable than most other topologies
More difficult to implement than other network topologies
Failure of the hub brings the entire network down
4. Mesh Topology
-Each computer on the network connected to every other
-Every device joined by point-to-point connections
Advantages:
-Mesh configuration creates redundant connections- minimizes disruptions if a single cable fails, or when the network is expanded
Disadvantages:
-Difficult to implement
-Expensive: requires more cable than other technologies
