How it works...

Simply, it calculates statistics over the captured data. Some important things to notice:

• The percentage always refers to the same layer protocols. For example, in the following screenshot, we see that logical link control has 0.5% of the packets that run over Ethernet, IPv6 has 1.0%, IPv4 has 88.8% of the packets, ARP has 9.6% of the packets and even the old Cisco ISK has 0.1 %—a total of 100 % of the protocols over layer 2 Ethernet.
• On the other hand, we see that TCP has 75.70% of the data, and inside TCP, only 12.74% of the packets are HTTP, and that is almost it. This is because Wireshark counts only the packets with the HTTP headers. It doesn't count, for example, the ACK packets, data packets, and so on: