STATE & FAQ ON TOPOLOGY This topology description of a network can also include or imply the nature of the data flow through the network. And practical term used in professional training.
💡 Bus topology A bus is the simplest physical topology. It consists of a single cable that runs to every workstation. This topology uses the least amount of cabling, but also covers the shortest amount of distance. Each computer shares the same data and address path. With a logical bus topology, messages pass through the trunk, and each workstation checks to see if the message is addressed to itself. If the address of the message matches the workstation’s address, the network adapter copies the message to the card’s on-board memory. It is difficult to add a workstation have to completely reroute the cable and possibly run two additional lengths of it. If any one of the cables breaks, the entire network is disrupted. Therefore, it is very expensive to maintain.
# INTERVIEW PREP GUIDE ABOUT NETWORK TOPOLOGY (PHYSICAL & LOGICAL)
🔹 What is network topology? ?
Network topology refers to the physical or logical arrangement of devices in a network.
🔹 How many types of network topology are there ?
Commonly six main types: Bus, Star, Ring, Mesh, Tree, and Hybrid.
🔹 What is physical topology ?
It describes how devices are physically connected.
🔹 What is logical topology ?
It describes how data flows within the network.
🔹 Why is network topology important ?
It affects performance, scalability, cost, and fault tolerance.
🔹 What is Bus topology ?
All devices are connected to a single backbone cable.
🔹 What is a backbone cable ?
It is the central communication line that connects all nodes in a bus network.
🔹 What is the advantage & disadvantage of bus topology ?
Advantage: Low cost and simple installation.
Disadvantage: If backbone fails, entire network fails.
🔹 What type of cable is commonly used in Bus Topology ?
Coaxial cable (like RG-58) is commonly used.
🔹 How do we know Bus Topology should be applied in network infrastructure ?
Bus topology is suitable when:
Network size is small, Budget is limited, Temporary network is required, Less number of devices (generally less than 20)
🔹 What network standard originally used Bus Topology ?
Early Ethernet standard 10BASE2 and 10BASE5.
🔹 What are terminators in Bus Topology ?
Resistors placed at both ends of the cable to absorb signals and prevent reflection.
🔹 Why are terminators important ?
Without terminators, signal reflection causes network collision.
🔹 What is signal reflection in bus networks ?
When signals bounce back from the cable end and interfere with new signals.
🔹 How does data travel in Bus Topology ?
Data travels in both directions along the backbone cable.
🔹 How does a device recognize its data ?
Each device checks the destination MAC address in the packet.
🔹 What protocol controls data transmission in Bus Ethernet ?
CSMA/CD (Carrier Sense Multiple Access with Collision Detection).
🔹 What is collision in Bus Topology ?
When two devices transmit data at the same time.
🔹 How can we calculate network efficiency in Bus Topology ?
Efficiency Formula:
Efficiency = Data Transmission Time / (Data Transmission Time + Propagation Delay)
🔹 How do you physically install Bus Topology ?
I) Install backbone cable (Required: Coaxial cable & Cutter, Crimping tool, BNC connectors, Cable tester)
II) Attach T-connectors (A connector used to attach devices to the backbone cable)
III) Connect devices (Its called nodes)
IV) Add terminators at both ends
🔹 How does bus topology affect bandwidth ?
Bandwidth is shared among all devices.
🔹 Can switches be used in Bus Topology ?
Traditional bus networks do not use switches.
🔹 Which topology replaced Bus Topology in enterprise networks ?
Mostly: Star topology & Spine-leaf architecture
🔹 Where can Bus Topology still be useful today ?
Small IoT networks, Industrial communication and Temporary network setups
🔹 Bus Topology Formula ?
In Bus Topology, all devices connect to one backbone cable.
Formula for Number of Links : 'L=N−1'
Where:
L = Number of links (?)
N = Number of devices (20)
L=20−1=19
So 19 links are required to connect 20 devices.
Bandwidth Sharing Formula : 'Bd = B/N'
Where:
B = Total bandwidth of bus topology (100)
Bd = Bandwidth per device (?)
N = Number of devices (20)
Bd = 100/20 = 5 Mbps
So 5 Mbps bandwidth will share per devices.
Formula for calculating cable requirement :
'Total Cable = Distance between nodes × (Number of Nodes – 1)'
If Distance between nodes = 5 meters
Number of nodes = 10
Total Cable = 5 × (10 – 1)
Total Cable = 45 meters
