Slice It Smart: Extend Your Capture Time With Packet Slicing

I would say packet slicing is one of the most critical techniques to understand.

Back in the day when we had hard drives with limited disk space and we needed to capture for long periods of time, we used packet slicing.

Packet slicing in Wireshark is one of those features that doesn’t get much love, but once you use it, you wonder how you ever captured packets without it. The basic idea is simple: instead of grabbing the entire packet payload, you only capture the first N bytes. For many troubleshooting and analysis tasks, that’s more than enough to see headers, flags, and protocol behavior without hauling around a ton of unnecessary data. One of the biggest benefits of packet slicing is smaller capture files. Full packet captures can balloon in size fast, especially on busy links or during long troubleshooting sessions. By slicing packets, you drastically reduce disk usage and make your capture files easier to store, share, and archive. This is especially handy when you need to send a capture to a colleague or attach it to a ticket without watching your email client cry. Packet slicing also improves performance during both capture and analysis. Writing less data to disk means less I/O overhead, which can be critical on laptops, virtual machines, or resource-constrained systems. Later on, when you open the capture in Wireshark, smaller files load faster, filters apply quicker, and scrolling through packets feels noticeably smoother. Less data means less waiting, Finally, packet slicing can help reduce risk and noise. By not capturing full payloads, you lower the chance of collecting sensitive or private data you don’t actually need for troubleshooting. In many cases—like diagnosing TCP handshakes, DNS issues, or routing problems—the headers tell the whole story. Packet slicing keeps your captures focused, efficient, and a little safer, proving that sometimes less really is more when you’re packet wrangling.

I use packet slicing for a slightly different situation. Sure, I might have a large drive but now the network speeds are much higher than 15 years ago. The other important reason why I use packet slicing is when the data is sensitive and we are not allowed to see the captured data. There are some other reasons covered in the video.

The point of the video is to introduce you to packet slicing but you should go look at your packet capture tool to determine if you have packet slicing and how to configure it.

---

ekahau's Free Webinar: Thursday, January 22, 2026 | 12:00 – 1:00 pm ET

Designing 5-star Wi‑Fi for Hotels