Summary
In this chapter, we looked at how packets are formed by reviewing the OSI model and understanding the various layers that exist in the model. We took this one step further by analyzing the structure of an IPv4 packet and performing a side-by-side comparison of this with a packet that we captured from our lab equipment. After providing a better understanding of what packets are and how they are constructed, we went on to use Wireshark to capture these packets. We made use of the mirror port that we created in the previous chapter, and we discussed the differences between capture filters and display filters.
Finally, we downloaded some PCAPs from an open source ICS lab and we used Wireshark to analyze the traffic that we found in these packet captures. We leveraged display filters to narrow down key network data, such as valid credentials, operational web portals, and working network cameras. Understanding and practicing these techniques and methods will allow you to have...