Many Network administrators are facing daily network problems on their infrastructures. There is an open source free tool on the market called Wireshark, which help them to identify and resolve the problem.
Wireshark is a network packet analyzer. It capture network packets and analyze them according to the OSI model.

How good packets look like, using Wireshark ?

Below you can see a network packet capture with good packets.

How bad packets look like ?

At the below image, you can understand how bad packet capture looks like.

What the wireshark TCP Flags means ?

Below, there are the most important TCP Flags, knowing these you will be able to read network packet capture from Wireshark.