Ethernet II
Ethertype field, no Length
Used by TCP/IP over Ethernet
OS': Microsoft, Unix, Novell
IEEE 802.3
Length field, LLC field
Used primarily by NetBEUI
OS': Spanning Tree, Microsoft, Novell, SNA
IEEE SNAP
LLC field contains "AAAA03"
SNAP field contains Ethertype
Used primarily by WiFi 802.11b/a/g
OS': Cisco CDP, AppleTalk, Frame Relay, Microsoft, Novell
Novell Raw
Length field, no LLC
Used primarily by early Netware for IPX
OS': Novell, Microsoft, print servers