On a router or switch, features known variously as port mirroring, port monitoring, and switched port analyzer (SPAN) allow network admins to duplicate network traffic and send it to a specified port, usually to export packets to a dedicated monitoring solution. Keep in mind this approach will also capture a limited view of the network on a wired network, for example, you’ll only see traffic on the local switch port your machine is connected to. For a more complete view of network traffic, you’ll want to put the interface in promiscuous mode or monitor mode. By default, network interfaces only pay attention to traffic destined for them. No matter what approach is used, packet capture works by creating copies of some or all packets passing through a given point in the network.Ĭapturing packets from your own machine is the easiest way to get started, but there are a few caveats. The approach used depends on the end goal. There’s more than one way to catch a packet! Packet captures can be done from a piece of networking equipment like a router or switch, from a dedicated piece of hardware called a tap, from an analyst’s laptop or desktop, and even from mobile devices. Unlike active reconnaissance techniques like port scanning, capturing packets can be accomplished without leaving any trace behind for investigators. From a threat actor’s perspective, packet captures might be used to steal passwords and other sensitive data. Following a data breach or other incident, packet captures provide vital forensic clues that aid investigations. Capturing packets is a common troubleshooting technique for network administrators, and is also used to examine network traffic for security threats. The term can also be used to describe the files that packet capture tools output, which are often saved in the. Packet Capture refers to the action of capturing Internet Protocol (IP) packets for review or analysis.

Packet Capture Advantages and Disadvantages.

Packet Capture and Packet Sniffer Use Cases.

Formats, Libraries, and Filters, Oh My!.

In this post, we’ll dive into what a packet capture is, how it works, what kind of tools are used, and look at some sample use cases. In the wrong hands, it can also be used to steal sensitive data like usernames and passwords. Packet capture is a vital tool used to keep networks operating safely and efficiently.

Microsoft packet capture tool