What are three security problems with Wi-Fi Protected Access （WPA）？（）

• A、WPA is based on the outdated IEEE 802.11i standard.
• B、WPA uses RSN，which uses the same base encryption algorithm as RC4.
• C、WPA requires a hardware upgrade that may not be supported by all vendors.
• D、WPA uses TKIP，which uses the same base encryption algorithm as WEP.
• E、WPA is susceptible to a DoS attack when it receives two packets in quick succession with bad MICs，forcing the AP to shut down the entire Basic Service Set （BSS） for one minute.
• F、WPA is susceptible to a security weakness when preshared keys are used.