The display filter syntax to filter out addresses between 192.168.1.1 – 192.168.1.255 would be ip.addr=192.168.1.0/24 and if you are comfortable with IP subnetting, you can alter the /24 to change the range. However, if the addresses are contiguous or in the same subnet, you might be able to get away with a subnet filter. One time-consuming approach would be to literally type out all the addresses you want to filter on. In this video, I respond to a question from one of my readers who wanted to create a display filter for many IP addresses. In either case, you will need to use a display filter to narrow the traffic down. Even when you have a capture filter, it may be too generic. You may not know what to focus on when you capture packets, resulting in no capture filter. A display filter is configured after you have captured your packets. A capture filter is configured prior to starting your capture and affects what packets are captured.

next chapter, well cover in detail how to capture and filter packets using Wireshark. Note that in Wireshark, display and capture filter syntax are completely different. Why the seven-layer OSI model matters IP networks and subnets. In this video, I review the two most common filters in Wireshark.

One of the keys to being an effective network troubleshooter when using a protocol analyzer is the ability to see patterns, which is where filters come into play.

Wireshark filter network subnet