Wi-Fi Career Pro Tip: Learn 802.11 Frame Analysis
Anyone new to Wi-Fi immediately learns that 802.11 technology operates at Layer 1 (PHY) and Layer 2 (MAC) of the OSI model. APs and WLAN client devices communicate via 802.11 frame exchanges at the MAC sublayer. Unlike many wired network standards such as IEEE 802.3, which uses a single data frame type, the IEEE 802.11 standard defines three major frame types: management, control, and data. These frame types are further subdivided into multiple subtypes.
I always tell people that one of the best things I did early in my Wi-Fi career was to teach myself 802.11 frame analysis.
Seventeen years later, 802.11 protocol analysis skills are still important and invaluable. Modern day WLAN protocol analyzer tools are more robust, but the 802.11 frame exchanges are constantly becoming more complex. As new 802.11 technologies such as 802.11ax become reality, the information inside 802.11 frame exchanges create a Wi-Fi mosaic that is tough to interpret.
No matter how much you might think you know about 802.11 frame analysis, you can always learn more. Recently, I purchased these two fantastic video training resources from Addison-Wesley Professional as part of the LiveLessons series.
Both of these videos are by Jerome Henry and James Garringer.
I have known both authors for a number of years and they are excellent teachers of the technology. Jerome Henry is CWNE #45 and James Garringer is CWNE #179.
Although there are many commercial WLAN protocol analyzers, Wireshark is open-source and the tool of choice for many WLAN professionals. If you are a Wireshark novice I highly recommend the Wireshark Fundamentals LiveLessons video training course which offers nearly five hours of instruction on using Wireshark to troubleshoot Ethernet and Wi-Fi networks, and the protocols they transport. You will learn Wireshark capture basics, customization, filters, command-line options and much more.
If you are interested in a deep-dive of 802.11 analysis, then I highly recommend the Wireshark for Wireless LANs LiveLessons video training course which offers more than eight hours of expert instruction on troubleshooting Wi-Fi networks using Wireshark. Nine lessons and sub-lessons will take you through learning the 802.11 MAC header, dissecting captured frames, advanced tools, and common WLAN problems that can be solved with proper analysis.
Both of these training videos are also an excellent study resource if you ever plan on taking the Certified Wireless LAN Professional (CWAP) exam.
Congratulations to both Jerome and James for creating an outstanding 802.11 technology learning resource.