Two files can contain the right packets yet produce an unhelpful combined sequence. Decide whether you need timestamp order or an explicit file-by-file arrangement before creating the working copy.

Keep both original captures and make a small manifest with their names, collection points and time ranges. Use files you are authorised to combine. If their provenance is uncertain, record that uncertainty rather than letting a single output file hide it.

Choose the ordering rule

Open capture A, choose File, Merge and select B. Chronological merging uses recorded timestamps; prepend and append instead place the selected file’s packets before or after the existing capture.

Suppose capture A contains times 1 and 4, while B contains 2 and 3. Merging chronologically should produce 1,2,3,4. Appending B to A should produce 1,4,2,3. Write the expected sequence first, then inspect the result by timestamp and source identity.

Save the combined work under a new name and retain the manifest. A correct four-packet sequence in this example verifies the selected ordering rule; it does not establish that two computers’ clocks agreed when they collected the packets.

Preserve what ordering cannot establish

Imagine an incident note that says one capture came from a laptop and the other from an appliance whose clock was not checked. Keep that qualification visible in the analysis. Sorting their numbers cannot independently establish the real-world order of closely spaced events.

If the intended question depends on that order, obtain suitable timing evidence from the responsible systems. Do not silently adjust timestamps merely to make an expected narrative appear. Record any later authorised correction separately from the original files.

Before handing over the merged copy, include the merge method, source manifest and unresolved timing assumptions. Ask the next reviewer to confirm the sequence they need before replacing your working arrangement. The result should make its ordering decision inspectable rather than turn two uncertain timelines into an apparently authoritative one.

Sources: Wireshark official guide.