On 4.3.2 firmware,
Backward Compatibility Mode - 802.11n SMs (like Force180, Force200) ---- 802.11ac AP (like ePMP 3000)
pure 802.11n mode - 802.11n SMs (like Force180, Force200) ---- 802.11n AP (like ePMP 2000)
Legacy SMs (Force200, Force180, any 802.11.n SM) will not be able to associate with ePMP 3000 or ePMP2000 AP (with cause INVALID SECURITY KEY) if SM > Configuration > QOS > Traffic Priority > Subscriber Module Priority is "High" or "Low".
Workaround is : Please change it to "Normal" and then only SM will be able to connect.
For the customers, who are planning on replacing ePMP 2000 with ePMP 3000 (using Backward Compatibility) or upgrading pure 802.11n (5GHz) network to 4.3.2, please make a note of above bug and before attempting to make SMs connect to ePMP3000, configure SMs settings as mentioned above. Having said that, we are working on fixing this issue ASAP. Thank you.
Just disabling “Traffic Priority” does not help. “Subscriber Module Priority” should be set to “Normal”. Then keeping “Traffic Priority” enabled or disabled is ok.
In other words, if “SM Priority” is on High or Low and Traffic Priority is disabled (after which you will not see SM Priority option), even in this scenario, issue (of not being able to connect to AP) exists.
This issue does not exist on pure 802.11ac mode - 802.11ac SMs (like Force300-16, Force300-25) ---- 802.11ac AP (like ePMP 3000). (As of now, AC SMs do not even have the QOS option in configuration and thus this issue do not exist.)