Trace an ICMP exchange through a switch

Verify two-PC reachability, then follow one ICMP request and reply through a 2960 switch in Simulation mode.

Packet Pete, your practice guide

Packet Pete
Predict the reading, then compare it with the measurement.

Cisco Packet Tracer

Desktop lab

Verify two-PC reachability, then follow one ICMP request and reply through a 2960 switch in Simulation mode.

Tier 3 · Install required · Cisco account required

Version tested: Cisco Packet Tracer 9.0.1 on Ubuntu 22.04 (Apptainer/Xvfb); project saved and execution captured 2026-09-10. Date: 2026-09-10.

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Steps

Screens captured against Cisco Packet Tracer Cisco Packet Tracer 9.0.1 on Ubuntu 22.04 (Apptainer/Xvfb); project saved and execution captured 2026-09-10 on 2026-09-10; the tool may have moved on — the text steps are the contract.

  1. Step 1

    Do
    Open lab.pkt and inspect PC0, Switch0, and PC1 in the Logical workspace.
    You will see
    PT displays PC0 — Switch0 — PC1, with both FastEthernet links green.
    Why it matters
    Naming the endpoints and intermediate device makes the expected path testable.

  2. Step 2

    Do
    Open PC0 Desktop → IP Configuration and verify its saved IPv4 settings.
    You will see
    The IPv4 Address field reads 192.168.1.10 with subnet mask 255.255.255.0.
    Why it matters
    A same-subnet exchange should use the switch directly and needs no router.

  3. Step 3

    Do
    From PC0, ping 192.168.1.11.
    You will see
    PT prints “Packets: Sent = 4, Received = 4, Lost = 0 (0% loss)”.
    Why it matters
    The reply count proves bidirectional delivery after address resolution.

  4. Step 4

    Do
    Switch from Realtime to Simulation and clear the event list.
    You will see
    The Simulation panel shows an empty event list and ICMP can be selected as the visible protocol.
    Why it matters
    A clean event list isolates the exchange being explained.

  5. Step 5

    Do
    Start one ping from PC0 and click Capture/Forward until it reaches PC1.
    You will see
    The event trace lists ICMP at PC0, then Switch0, then PC1.
    Why it matters
    The device order distinguishes endpoint processing from Layer-2 forwarding.

  6. Step 6

    Do
    Open the ICMP PDU at Switch0 and inspect its inbound and outbound Layer-2 headers.
    You will see
    PDU Information identifies source PC0 and destination 192.168.1.11 and shows the Ethernet II header on both sides of Switch0.
    Why it matters
    The PDU window exposes the real per-port Layer-2 forwarding details hidden by the topology view.

  7. Step 7

    Do
    Continue Capture/Forward until the reply returns to PC0, then return to the Command Prompt and save.
    You will see
    The completed command prints “Packets: Sent = 4, Received = 4, Lost = 0 (0% loss)”.
    Why it matters
    Following both directions prevents a sent request from being mistaken for completed connectivity.

Chapter checks

These questions refer to the chapter’s examples. Use the return links to review their answers.

  1. A team says, "We chose MQTT, so the network architecture is solved." What is the best response?

    Return to the chapter’s knowledge check

  2. A gateway receives constrained-device messages on one side and publishes them to a cloud broker on the other. Which review record is most important?

    Return to the chapter’s knowledge check

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