Routing algorithms are techniques used in computer networks to determine the best path for data to travel from the sender to the receiver. Since data often passes through several routers before reaching its destination, routing algorithms analyze factors such as distance, network traffic, link cost, and reliability to select an efficient route. These algorithms may be static (non-adaptive), where routes are fixed, or dynamic (adaptive), where routes change based on current network conditions.

1. Classification of Routing
Algorithms
Simplified Notes for BCA Students

2. Routing Basics
• Routing decides the path data follows from
source to destination.
– Routers use a routing table to select the best path.

3. Classification of Routing Algorithms
• Adaptive (Dynamic) Routing
– Non-Adaptive (Static) Routing
– Hybrid Routing

4. Adaptive (Dynamic) Routing
• Updates routes based on network traffic and
conditions.
– Used in large and complex networks.

5. Types of Adaptive Routing
• Isolated Routing - Each router takes decision
independently.
– Centralized Routing - Central node decides routes.
– Distributed Routing - Routers share information
with neighbors.

6. Non-Adaptive (Static) Routing
• Routes do not change once selected.
– Used in small and simple networks.

7. Types of Static Routing
• Flooding - Sends packets on all outgoing paths.
– Random Walk - Sends packet to a random next
node.

8. Hybrid Routing
• Combination of Adaptive and Static routing.
– Used when network is divided into multiple
regions.

9. Common Routing Protocols
• RIP - Uses Hop Count (Small Networks)
– IGRP - Improved RIP (Cisco)
– OSPF - Uses Dijkstra Algorithm (Large Networks)
– EIGRP - Hybrid routing (Cisco)
– BGP - Used on the Internet between ISPs

10. Summary
• Dynamic routing changes based on network
conditions.
– Static routing remains fixed.
– Hybrid uses both based on network needs.