Wireshark is a powerful tool for network support technicians who are trying to troubleshoot connectivity issues and optimize network performance. In this series, we have covered a number of features in Wireshark that can be particularly useful for troubleshooting network issues, including:

• “Follow TCP Stream”
• “Decode As”
• “IO Graphs”
• “Expert Infos”
• “Time Sequence Graph (tcptrace)”
• “Conversation Filter”
• “Graphical Time Sequence (grep)”
• “Statistics”

In the following summary, we will provide a brief overview of each of these features and how they can be used to troubleshoot network issues.

• “Follow TCP Stream” allows you to see all of the packets in a particular TCP stream in a single window, making it easier to understand the conversation between two devices.
• “Decode As” allows you to change the way that Wireshark decodes and displays a particular protocol, which can be useful when the default decoding is not correct or when you want to see more detailed information about the protocol.
• “IO Graphs” allows you to create graphs of packet and byte rates over time, which can help you identify trends and patterns in network traffic.
• “Expert Infos” displays alerts and warnings about potential problems with the packets being captured, such as retransmissions or out-of-order packets.
• “Time Sequence Graph (tcptrace)” displays a graph of TCP packet sequence numbers over time, which can help you identify problems with the TCP connection.
• “Conversation Filter” allows you to filter the packets being displayed based on their source and destination addresses, which can be useful when you are trying to focus on a specific conversation.
• “Graphical Time Sequence (grep)” displays a graph of packet transmission times over time, which can help you identify trends and patterns in network traffic.
• “Statistics” provides a wide range of statistical information about the packets being captured, including “Protocol Hierarchy,” “Endpoints,” “IO Graphs,” “Conversations,” “Flow Graph,” “TCP Stream Graphs,” and “HTTP.”
• “Protocol Hierarchy” displays a graphical representation of the protocols being used on your network, with the most frequently used protocols at the top. It is useful for identifying potential problems with your network.

Overall, Wireshark is a powerful tool that can be used to troubleshoot a wide range of network connectivity issues. By using the features discussed in this series, network support technicians can quickly and effectively identify and resolve problems with their networks, improving overall performance and reliability. Whether you are a seasoned network support professional or just starting out, learning how to use Wireshark is a valuable skill that can help you troubleshoot and optimize your network.

Using Wireshark to Troubleshoot Network Connectivity Issues: Statistics

In addition to the “Follow TCP Stream,” “Decode As,” “IO Graphs,” “Expert Infos,” “Time Sequence Graph (tcptrace),” “Conversation Filter,” and “Graphical Time Sequence (grep)” features, Wireshark also includes a tool called “Statistics” that provides a wide range of statistical information about the packets being captured.

To use the “Statistics” feature, simply select the “Statistics” menu and then choose the type of statistical information that you want to view. Wireshark provides a number of different options, including “Protocol Hierarchy,” “Endpoints,” “IO Graphs,” “Conversations,” “Flow Graph,” “TCP Stream Graphs,” and “HTTP.”

Part A: How to Use the Protocol Hierarchy
To use the “Protocol Hierarchy” option in the “Statistics” feature in Wireshark, follow these steps:

Select the “Statistics” menu and then choose “Protocol Hierarchy.”
In the “Protocol Hierarchy” window, you will see a graphical representation of the protocols being used on your network, with the most frequently used protocols at the top.
To view more detailed information about a specific protocol, click on the protocol in the graph. This will open a new window with a breakdown of the packets being captured for that protocol.

Part B: Why the Protocol Hierarchy is Useful
The “Protocol Hierarchy” option in the “Statistics” feature is useful for a number of reasons:

It provides a high-level overview of the protocols being used on your network. By seeing which protocols are being used the most, you can get a sense of the types of traffic that are generating the most activity on your network.

It helps you identify any potential problems with your network. For example, if you see that a particular protocol is being used much more frequently than others, it could be a sign that there is a problem with that protocol or that it is being used excessively.

It allows you to drill down into specific protocols to get more detailed information. By clicking on a specific protocol in the graph, you can open a new window with a breakdown of the packets being captured for that protocol, which can help you identify any issues with the packets or the protocol itself.

It helps you optimize your network by identifying any protocols that are using up too much bandwidth or causing other performance issues. By identifying and addressing these issues, you can improve the overall performance of your network.

Overall, the “Protocol Hierarchy” option in the “Statistics” feature in Wireshark is a valuable tool for network support technicians who are trying to troubleshoot connectivity issues and optimize network performance.

Using Wireshark to Troubleshoot Network Connectivity Issues: Graphical Time Sequence (grep)

In addition to the “Follow TCP Stream,” “Decode As,” “IO Graphs,” “Expert Infos,” “Time Sequence Graph (tcptrace),” and “Conversation Filter” features, Wireshark also includes a tool called the “Graphical Time Sequence (grep)” feature that allows you to visualize the flow of traffic between two devices over time in a graphical format.

To use the “Graphical Time Sequence (grep)” feature, simply select the “Statistics” menu and then choose “TCP Stream Graphs -> Time-Sequence Graph (Stevens).” This will open a new window that allows you to choose the stream that you want to visualize.

The “Graphical Time Sequence (grep)” feature shows the flow of traffic between two devices over time, with the x-axis representing time and the y-axis representing the sequence numbers of the packets being sent. You can use this tool to identify any problems with the flow of traffic, such as delays or missing packets.

By using the “Graphical Time Sequence (grep)” feature in combination with other diagnostic tools, such as the “Follow TCP Stream” and “IO Graphs” features, you can gain a deeper understanding of the traffic on your network and identify potential problems. With a little bit of practice and a thorough understanding of the features and techniques available in Wireshark, you can become an expert at troubleshooting network issues and keeping