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DWS-1008 User’s Manual
D-Link Systems, Inc.
Appendix A - Troubleshooting
The following command shows statistics for snoop filter
snoop1
:
DWS-1008#
show snoop stats snoop1
Filter
Dap Radio Rx Match Tx Match Dropped Stop-After
=============================================================
snoop1 3 1 96 4 0
stopped
Preparing an Observer and Capturing Traffic
To observe monitored traffic, install the following applications on the observer:
• Ethereal or Tethereal Version 0.10.8 or later
• Netcat (any version), if not already installed
Ethereal and Tethereal decode 802.11 packets embedded in TZSP without any
configuration.
Use Netcat to listen to UDP packets on the TZSP port. This avoids a constant flow of ICMP
destination unreachable messages from the observer back to the radio. You can obtain
Netcat through the following link:
http://www.securityfocus.com/tools/139/scoreit
If the observer is a PC, you can use a Tcl script instead of Netcat if preferred.
1.
Install the required software on the observer.
2.
Configure and map snoop filters in MSS.
3.
Start Netcat:
• On Linux or Unix, use a command such as the following:
nc -l -u -p 37008
ip-addr
> /dev/null &
• On Windows, use the following command:
netcat -u -p 37008 -v -v
Where
ip-addr
is the IP address of the Distributed AP to which the snoop filter is
mapped. (To display the Distributed AP’s IP address, use the
show dap status
command.)
4.
Start the capture application:
• For Ethereal capture, use
ethereal filter port 37008
.
• For Tethereal capture, use
tethereal -V port 37008
.
5.
Disable the option to decrypt 802.11 payloads. Because the AP always decrypts the
Summary of Contents for DWS-1008
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