Symptoms
Users have reported that when using an Intel Wireless N adaptor with the Wired Equivalent Privacy (WEP) or Temporal Key Integrity Protocol (TKIP) security encryption, they are reaching a data rate of only 54 Mbps. The adaptor is working as designed as the Institute of Electrical and Electronics Engineers (IEEE) 802.11n draft prohibits using high throughput with WEP or TKIP as the unicast cipher.
If either of these two encryption methods are used, the data rate will drop to 54 Mbps as 802.11n requires WPA2-AES or WPA2-TKIP to be enabled to operate at 802.11n data rates. Newer Intel wireless adapter client drivers connect using a legacy IEEE 802.11g connection rather than failing to connect altogether, which complies with the IEEE 802.11n draft.
Note: More details including solutions for the issue and a list of Intel devices that are affected can be found on the following Intel web site. Intel WiFi Products - Data rate will not exceed 54 Mbps when WEP or TKIP encryption is configured
Below is a list of the affected Intel Wireless adapters (please note that other Intel Wireless adapters may also be affected by the issue).
Intel® Centrino® Advanced-N 6200
Intel® Centrino® Advanced-N 6205
Intel® Centrino® Advanced-N 6230
Intel® Centrino® Ultimate-N 6300
Intel® Centrino® Wireless-N + WiMAX 6150
Intel® Centrino® Advanced-N + WiMAX 6250
Intel® Centrino® Wireless-N 100
Intel® Centrino® Wireless-N 130
Intel® Centrino® Wireless-N 1000
Intel® Centrino® Wireless-N 1030
Intel® WiFi Link 1000
Intel® WiFi Link 5300 and Intel® WiFi Link 5100 products
Intel® WiMAX/WiFi Link 5350 and Intel® WiMAX/WiFi Link 5150 products
Intel® Wireless WiFi Link 4965AGN
Note: IEEE 802.11g is an amendment to the IEEE 802.11 specification that extends the throughput up to 54 Mbps using the same 2.4 GHz band as 802.11b. IEEE 802.11n is an amendment to the IEEE 802.11 specification to improve network throughput over the two previous standards (802.11a and 802.11g) with a significant increase in the maximum raw data rate from 54 Mbps to 600 Mbps.
Resolution
Below are some solutions provided by Intel to help resolve this issue.
Contact your WiFi access point (AP) or router manufacturer to download the latest firmware version, or to obtain information on particular models supporting High Throughput.
Disable "packet bursting" or similar feature that may be enabled on the AP or router.
Configure the Wi-Fi client device's profile to use Wi-Fi Protected Access (WPA2-AES or WPA2-TKIP). You may also choose to configure an unsecured profile, but this option is NOT recommended.
Configure the AP or router to match the client profile.
