Q & A on Types of Ethernet Q: I'm reading your book but I don't clear understand the names of different ethernet frame types. You describe two forms of Ethernet: one with a MAC type field in the header and one using 802.2-llc (a llc/snap-header). In many network-environments I meet the terms: ETHERNET 802.3 ETHERNET 802.2 ETHERNET SNAP ETHERNET II where is here the equivalent to the system above, which name has the ethernet-frame in Section 7.8 and what means ETHERNET II ? A: The 802 numbers come from the IEEE standards. Standard 802.3 specifies the Ethernet Medium Access Control (MAC) details. Among other things, 802.3 defines the Ethernet frame format. IEEE standard 802.2 specifies Logical Link Control (LLC) layer, and is an alternative to having a type field in the header. The term "Ethernet SNAP" refers to the LLC/SNAP header defined by the 802.2 standard. My assistant dug up this item about Ethernet 2: Except for obscure technical details "Fast" Ethernet is regular Ethernet with a clock rate ten times faster, period. Ethernet_II is Novell's way of saying "industry standard Ethernet framing", independent of clock rate.