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WLAN Analyzer and Decoder - CommView for WiFi

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Introduction
About CommView for WiFi
What's New
Using the Program
Driver Installation
Overview
Main Menu
Nodes
AP and Station Details Window
Channels
Latest IP Connections
Packets
Logging
Viewing Logs
Rules
Advanced Rules
Alarms
WEP/WPA Keys
Reconstructing TCP Sessions
Reconstructing UDP Streams
Searching Packets
Statistics and Reports
Using Aliases
Packet Generator
Visual Packet Builder
NIC Vendor Identifier
Scheduler
Node Reassociation
Using Remote Agent for WiFi
Using RPCAP
Using Aruba Remote Capture
Port Reference
Setting Options
Frequently Asked Questions
VoIP Analysis
Introduction
Working with VoIP Analyzer
SIP and H.323 Sessions
RTP Streams
Registrations, Endpoints, and Errors
Call Logging and Reports
Call Playback
Viewing VoIP Logs
Working with Lists in VoIP Analyzer
NVF Files
Advanced Topics
Monitoring 802.11n and 802.11ac Networks
Understanding CRC and ICV Errors
Understanding WPA Decryption
Understanding Signal Strength
Capturing A-MPDU and A-MSDU Packets
Using CommView for WiFi in a Virtual Machine
Multi-Channel Capturing
Spectrum Analysis
Capturing High Volume Traffic
Running CommView for WiFi in Invisible Mode
Command Line Parameters
Exchanging Data with Your Application
Custom Decoding
CommView Log Files Format
Information
How to Purchase CommView for WiFi

Multi-Channel Capturing

CommView for WiFi is capable of capturing data from multiple channels simultaneously if one uses multiple compatible USB adapters. The following 802.11n USB adapters can be used for multi-channel capturing: D-Link DWA-160 v.A1, v.A2, v.B2, and v.C1, Edimax EW-7733UnD, Linksys AE3000, NETGEAR WN111 v2, NETGEAR WNDA3100 v1, Proxim ORiNOCO 8494, SMC Networks SMCWUSB-N2, Sony UWA-BR100, TP-Link TL-WDN3200, TP-Link TL-WN721N, TP-Link TL- WN722N, TP-Link TL-WN821N v1, v2, and v3, TP-Link TL-WN822N v1 and v2, Ubiquiti SR71-USB, and CACE Technologies AirPcap Ex or NX. The following 802.11ac USB adapters can be used for multi-channel capturing: Belkin F9L1109 v1, D-Link DWA-180 rev A1, D-Link DWA-182 rev C1, Edimax EW-7822UAC, EnGenius EUB1200AC, Linksys WUSB6300, TP-LINK Archer T4U, TRENDnet TEW-805UB, and ZyXEL AC240.

Note that different types of adapters cannot be mixed; all of the adapters should be of the same model. When multiple adapters are connected, the following interface elements are changed:

· The channel selection control on the Capture pane allows you to select multiple channels. You can select multiple channels by holding the Ctrl key. The number of channels that you select cannot exceed the number of plugged in USB adapters.
· The Channel Indicator pane displays multiple indicators, the number of which is equal to the number of plugged in USB adapters.

This is illustrated on the screen shot.

When using multiple adapters, please consider the following:

1. Power consumption. A single adapter might need up to 450 mA of power. A single USB 2.0 port can provide up to 500 mA. A single USB 3.0 port can provide up to 900 mA. A typical modern laptop has two USB 3.0 ports, so you should either use one adapter per port, or you can use a USB hub, but if you plug in thee adapters into a USB 3.0 hub, you will exceed the 900 mA limit, which might cause undesirable effects, e.g. the adapters might stop capturing packets silently.

2. Channel switching time. When CommView for WiFi is working in scanner mode, switching channels takes some time, between 20 and 80 milliseconds per adapter. Consider a scan of 12 channels with the scanner interval of 250 ms per channel and the channel switch time of, say, 60 ms. The total time would be (250 + 60) * 12 = 3.72 seconds if you use a single adapter. If you use three adapters, the total time would be (250 + 60 *3) * 4 = 1.72 seconds. That is x2.16 times better, not x3 times better. Thus, adding adapters adds channel switching overhead. If you use 12 adapters, which is possible in theory, it will take 250 + 60 * 12 = 0.97 seconds to scan 12 channels, so you're not gaining much.

That said, we don't recommend using more than two or three adapters.

multi usb