Turbo mode
Next up was checking Condition 1 performance using the Belkin card with Turbo mode enabled. Since "Turbo" / Xpress / frame-bursting is aimed at improving mixed WLAN performance, I didn't expect to see any improvement with a single 11g client and that's what I found. I did run some tests with one 11b and one 11g client, but since Broadcom disses Chariot-based testing for evaluating Xpress' performance and also stresses that you need multiple 11g and 11b clients to really see Xpress' advantage, I decided to put that testing aside until I discuss test techniques with Broadcom.
11b Protection
I also ran my closest-range Condition 1 tests on NETGEAR WG511 (Intersil GT), and NETGEAR WAG511 (Atheros 5001X+) cards with the AP's 11b protection enabled and disabled to check for interoperability with other manufacturers chipsets. The results are shown in Figures 8 and 9, which compare Condition 1 results for the Belkin and two NETGEAR adapters in both protection modes.
Figure 8: Broadcom, Atheros, Intersil Condition 1 throughput - 11b protection off
(click on the image for a full-sized view)
Figure 9: Broadcom, Atheros, Intersil Condition 1 throughput - 11b protection on
(click on the image for a full-sized view)
Note that the Belkin (Broadcom) and NETGEAR WG511 (Intersil GT) adapters had 11g-compliant drivers installed, but the NETGEAR WAG511 (Atheros 5001X+) was run with its latest, but still draft-11g driver. I have no explanation for the WG511's poorer performance and even ran the tests multiple times to see if I was seeing some sort of startup / warmup transient performance.
Note also that the above tests were performed with no 11b clients in range. Those test results are next.