Enterprise Wi-Fi Analysis & Troubleshooting – CWAP Certification (CWAP) – Details

Detaillierter Kursinhalt

Principles of WLAN Communication

  • 802.11 Working Group
  • OSI reference model and the 802.11 PHY and MAC
  • Communication sublayers and data units
  • WLAN architecture components
  • Organization of station forwarding
  • Addressing and internetworking operation
  • Modern WLAN product architectures

Physical (PHY) and MAC Layer Formats and Technologies

  • Physical layer functions
  • Preamble function and format
  • Header purpose and structure
  • Analysis of PHY problems
  • Physical PPDU formats
  • 802.11b
  • 802.11a
  • 802.11g
  • 802.11n
  • MAC frame components
  • MAC encapsulation
  • Fields and subfields of the MAC header
  • Frame Control
  • Frame types and subtypes and their uses
  • Addressing
  • Frame body
  • Data frame format
  • Control frame format
  • Management frame format
  • Information elements and fields

Protocol Operation

  • Beaconing and synchronization
  • Scanning
  • Client state machine
  • 802.11 contention
  • QoS
  • Admission control
  • Band steering and airtime fairness mechanisms
  • Fragmentation
  • Acknowledgments and Block acknowledgments
  • Protection mechanisms and backward compatibility
  • Power management
  • Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC)
  • Security components, methods, and exchanges
  • Roaming procedures exchanges
  • Future protocol enhancements

802.11n

  • Transmit beamforming
  • Spatial multiplexing
  • Maximal Ratio Combining (MRC)
  • Space-Time Block Coding
  • 40 MHz channels
  • Frame aggregation
  • HT-OFDM format
  • Modulation and Coding Schemes (MCS)
  • HT frame formatting
  • And More

Protocol Analysis Tools and Methodology

  • Troubleshooting methodology
  • Protocol analyzer types
  • Analysis NIC/adapter selection and constraints
  • Interpreting results based on location
  • Analyzer settings and features
  • Filtering and channel scanning
  • Interpreting decodes
  • Using advanced analysis features
  • Assessing WLAN health and behavior factors
  • Evaluating network statistics
  • Troubleshooting common problems
  • Wired analysis to support wireless network issues

Spectrum Analysis Tools and Methodology

  • Radio frequency behavior review
  • Visualizing RF domains using spectrum measurement tools
  • Spectrum analyzer types and operation
  • Analyzer specifications and characteristics
  • Understanding spectrum data presentation
  • Interpreting plots and charts
  • Common WLAN spectrum analyzer features
  • Identifying transmit patterns
  • Device classification and network impact
  • Recognizing transmit signatures
Hands-on Lab Exercises

Protocol Analyzer Setup, Use, and In-Depth Analysis

  • Basic installation and familiarity with capabilities, configuration, and data display
  • Opening, collecting, saving, and modifying capture files
  • Exploring common features like device naming and prioritization, filtering traffic, and using coloring rules as analysis aides
  • Configuration of the tool to perform live captures based on a set of desired collection criteria
  • Identifying significant network behaviors, metrics, and statistics used to identify and isolate network problems
  • Using expert features of the analyzer, such as conversation analysis
  • Remote packet capture with an AP

Understanding Frame Components

  • Understanding the MAC header
  • Comparing the three major frame types and their subtypes
  • Analyzing frame formats of individual frame types
  • Analyzing 802.11n frame components
  • Identifying what additional information is reported by protocol analyzers
  • Understanding what information is not visible in protocol analyzers

Frame Exchanges

  • Connectivity exchanges and sequences
  • Legacy and modern security exchanges
  • ERP and HT protection mechanisms
  • Power save behavior
  • Acknowledgments, block acknowledgments, and supporting action frames
  • Dynamic rate switching
  • Band steering
  • And more

Troubleshooting Common Problems

  • Troubleshooting connectivity exchanges
  • Troubleshooting 802.1X and EAP exchanges
  • Troubleshooting roaming

Spectrum Analyzer Setup, Use, and In-Depth Analysis

  • Installing the analyzer and becoming familiar with display and navigation
  • Understanding the “RF perspective” provided by each plot and chart
  • Using built-in features like markers and traces as well as automated device identification
  • Characterizing the behaviors of an interference source
  • Assessing the impact of an interference source
  • Determining the impact of transmitter proximity on interference and spectrum displays
  • Identifying signatures of common transmitters
  • Remote spectrum analysis with an AP