Experiment 3.2 — Bus, Star, Ring and Hybrid Topologies

Manual pages: 20–25 | Tool: Cisco Packet Tracer

AIM

To visualize Bus, Star, Ring and Hybrid network topologies and observe packet flow between devices.

TOPOLOGIES

BUS DEMO: PC0  PC1  PC2  PC3
              \ | /  /
               Hub0
STAR: PC0/PC1/PC2/PC3 --> Switch0 (central)
RING: PC0-SW0---SW1-PC1
           |     |
      PC3-SW3---SW2-PC2
HYBRID: (PC0,PC1)-Switch0--Hub0--Switch1-(PC2,PC3)

Note: The manual's hub-based “Bus” demonstration is physically star-shaped but mimics a shared Ethernet medium; a true historical bus uses a common backbone.

EXECUTION STEPS

1. Bus demonstration: New file → place 4 PCs + 1 Hub-PT. Connect each PC to different hub Ethernet ports using Straight-Through.
2. Star: New file → 4 PCs + 1 2960 Switch. PC FastEthernet0 → Switch Fa0/1..Fa0/4.
3. Ring: New file → 4 switches + 4 PCs. Form switch ring: SW0–SW1–SW2–SW3–SW0. Attach one PC per switch. STP might block a redundant port (orange).
4. Hybrid: New file → 4 PCs, 2 switches and 1 hub. PC0/1→SW0→Hub0→SW1→PC2/3.
5. For each topology, set addresses in IP_AND_PING.txt. Gateway is blank because there's no router.
6. PC0 → Command Prompt: ping all other PCs. Switch to Simulation, Add Simple PDU PC0→PC3; use Capture/Forward.
7. Save four separate .pkt files.

EXPECTED OUTPUT

PC0> ping 192.168.1.4
Reply from 192.168.1.4 ...
Packets: Sent=4, Received=4, Lost=0
Simulation: PC0 -> PC3, ICMP, Successful

Hub repeats received frames; switch learns MAC addresses; ring STP can block a redundant link. See EXPECTED_OUTPUT.txt.

RESULT

Thus, Bus, Star, Ring and Hybrid topologies were created and visualized, and packet flow was successfully simulated and compared using Packet Tracer.

VIVA

• Hub: Layer 1, repeats incoming signals. Switch: primarily Layer 2, learns MAC addresses.
• STP prevents loops in a switched ring. Hybrid combines topology structures.