Case Study: Small Office Network Upgrade
Scenario: A small office has decided to upgrade its network. They currently have 10 computers connected to a single hub, and they're experiencing slow network performance. They want to improve their local network and add a connection to a branch office.
Part 1: Replacing the Hub with a Switch
Current setup (with hub):
10 computers connected to a 100 Mbps hub When Computer A sends data to Computer B, all computers receive the data Only one computer can send data at a time (half-duplex) Upgraded setup (with switch):
10 computers connected to a 100 Mbps switch When Computer A sends data to Computer B, only Computer B receives the data Multiple pairs of computers can communicate simultaneously (full-duplex) Results:
Reduced unnecessary traffic: Only the intended recipient gets the data. Increased throughput: Multiple simultaneous communications are possible. Improved security: Devices don't see traffic not intended for them. Part 2: Adding a Router for Inter-office Communication
The office now wants to connect to their branch office. They add a router to their network.
Setup:
Main Office Network: 192.168.1.0/24 Branch Office Network: 192.168.2.0/24 Router has two interfaces: Interface A: 192.168.1.1 (connected to main office switch) Interface B: 192.168.2.1 (connected to branch office network) Routing Process:
Computer A (192.168.1.10) in the main office wants to send data to Computer B (192.168.2.20) in the branch office. Computer A sends the packet to its default gateway (the router's Interface A: 192.168.1.1). The router receives the packet and checks the destination IP (192.168.2.20). The router consults its routing table: 192.168.1.0/24 is connected to Interface A 192.168.2.0/24 is connected to Interface B The router determines that the destination IP (192.168.2.20) matches the network on Interface B. The router forwards the packet out through Interface B towards the branch office. 
Case Study