I see in the 802.11 header that there is no ethertype field. How is that possible ?
If 802.11 is carrying any higher layer protocol, it's 802.11 header Type/Subtype field will be "Data" (0x20) or "Qos Data" (0x28), and there will usually be a SNAP header (rfc1042) above the 802.11 header which will convey the type of payload (IP, ARP etc.)
It is of course in theory able to carry any layer 2 protocol, and use any LLC header.
来源：https://stackoverflow.com/questions/32233879/is-there-an-ethertype-field-in-802-11-header