Wireless Performance, Continued
Figure 5: Security mode performance comparison
Belkin F5D7010 client - Run 1
(click on the image for a full-sized view)
Figure 6: Security mode performance comparison
Belkin F5D7010 client - Run 2
(click on the image for a full-sized view)
When I switched over and ran the same tests with the Belkin card, the first run in Figure 5 shows the WEP128 and WPA-PSK / AES modes fared the worst with reductions in average throughput of 23% and 19% respectively, primarily caused by drops in throughput to under 16Mbps for at least half of each of the test runs. WPA-PSK / TKIP did a little better, turning in a 17% throughput hit, primarily due to a smoother throughput profile. The second Belkin card run, however, finally produced the behavior I'd expect, with significant throughput reduction (22%) only in the WPA-PSK / TKIP mode.
My conclusion? I suspect there's still some tuning left to do in the WLA2's code, which hopefully can make all clients - or at least all Broadcom-based clients - behave more like the Belkin card's second run.
NOTES:
- Although Buffalo provides the selection of Auto (b/g), WiFi (11b-only), and Turbo (11g-only) modes, and the ability to disable 802.11b protection, I ran all the above tests in the WLA2's defaults of Auto mode and 11b protection disabled.- The WLA2's "Turbo" mode does not enable Broadcom's throughput enhancement Xpress technology, but just prevents clients that don't support the higher speed OFDM modes, i.e. 11b clients, from connecting.
802.11g Wireless Performance Test Results
| Test Conditions
| Firmware/Driver Versions AP f/w: | ||||
|---|---|---|---|---|---|
| Test Description | SNR (dB) | Transfer Rate (Mbps) | Response Time (msec) | UDP stream | |
| Throughput (kbps) | Lost data (%) | ||||
| Client to AP - Condition 1 | 58 | 20.8 [No WEP] 18.9 [w/ WEP] | 1 (avg) 2 (max) | 499 | 0 |
| Client to AP - Condition 2 | 26 | 16.9 | 1 (avg) 2 (max) | 499 | 0 |
| Client to AP - Condition 3 | 13 | 8.6 | 1 (avg) 3 (max) | 499 | 0 |
| Client to AP - Condition 4 | 16 | 6.8 | 1 (avg) 3 (max) | 498 | 0 |