Ethereal-users: [Ethereal-users] 802.11 acknowledgement missing

Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.

From: Shashwat Srivastav <ssrivast@xxxxxxxxxxxxxx>
Date: Sun, 20 Jul 2003 01:33:22 -0500
Hello,

According to IEEE 802.11, every unicasted packet is acknowledged. I captured a TCP data transfer session with ethereal, but saw no 802.11 Frame Control acknowledgement packets during this time. A desktop machine, connected to Cisco Aironet 350 Access Point sent TCP data to laptop with Cisco 350 wireless card. The card was in monitor mode. No capture filter was used. No packet showed up when I used display filter " wlan.fc.type == 1 and wlan.fc.subtype == 13 " for seeing packets of 802.11 acknowledgement type. I can see other type of 802.11 packets like beacon frame.

The version information is -
ethereal 0.9.13
Compiled with GTK+ 1.2.10, with libpcap current-cvs.tcpdump.org.2003.07.17, with libz 1.1.4, without UCD_SNMP or Net-SNMP, without ADNS
Running on Linux 2.4.21

Has anybody seen similar behavior. Any suggestion for diagnosing this would be helpful.

Thanks,
Shashwat