TCP/IP Network Traffic Analysis with Wireshark Training Course

Overview of Network Analysis

1. Fundamentals of the OSI reference model and TCP/IP networks.
2. Troubleshooting tools and methodologies.
3. Introduction to Wireshark.
4. What is Wireshark? Portable versions and relevant resources.
5. Wireshark GUI layout: Panes (Packet List, Details, Packet Bytes), Status Bar, etc.
6. Architecture and processing flow: Identifying data that cannot be observed via Wireshark and the reasons why.
7. Supported protocols and dissectors.
8. Configuring preferences and settings, both global and profile-specific.
9. Understanding time values.
10. Practical lab exercises.

Capturing Traffic

1. Key considerations before starting a capture.
2. Promiscuous mode.
3. Setting up capture filters.
4. Defining automatic stop criteria.
5. Performing remote captures.
6. Practical lab exercises.

Traffic Analysis: Tools and Approaches

1. Creating an analysis checklist.
2. Leveraging features: name resolution, colorization, marking, ignoring, commenting, and utilizing time references and shifts.
3. Understanding the Expert System.
4. Accessing options via right-click functionality.
5. Interpretation (reference patterns) and the impact of OS/driver offload features.
6. Saving analysis results.
7. Lab exercises and case studies.

Traffic Analysis: Tools and Approaches (Continued)

1. Filtering traffic: Display filters (preparing dynamic filters, macros) and stream following.
2. Quantitative analysis.
   1. Basic predefined descriptive statistics and summaries: Capture Properties, Protocol Hierarchy, Conversations, Endpoints, Packet Lengths, and IP-specific data.
   2. Protocol-specific analysis (e.g., TCP Stream Graphs).
   3. Advanced custom statistics using I/O Graph.
   4. Flow visualization.

Traffic Analysis: Protocols

1. Data-Link Layer: Ethernet II.
2. Network Layer: IPv4.
3. Transport Layer: TCP and UDP.
   1. Packet loss and recovery mechanisms.
   2. Handling previous segment loss and Out-of-Order Segments events.
   3. Duplicate ACKs and Fast Retransmissions.
   4. TCP Retransmissions.
   5. Zero Window, window changes, and other window-related issues.
4. Application Layer: HTTP and FTP.
5. Lab exercises and case studies.

Traffic Analysis: Common Issues in Network Performance Assessment

1. Identifying the root causes of performance problems.
2. Analyzing packet loss.
3. Bandwidth issues and the layered approach to measurement.
4. Latency: assessing end-to-end latency and visualization techniques.
5. Practical lab exercises.
6. Command-line tools (Wireshark ecosystem):
   1. tshark (terminal-based Wireshark), dumpcap, rawshark, and tcpdump
   2. editcap, mergecap, capinfos, and text2pcap.

Advanced Topics

1. Advanced filters and grouped I/O statistics.
2. Summary and Q&A session.