EtherTypein

EtherTypein is not a widely recognized term in standard networking literature. It may be a misspelling, a coined term from a specific project, or a mistaken reference to EtherType. Because it does not correspond to a widely adopted standard, there is no formal definition or specification universally associated with the name.

If the term is intended to refer to EtherType, it describes a 16-bit field used in Ethernet frames to indicate the protocol of the payload in Ethernet II framing. The EtherType field appears after the destination and source MAC addresses and helps demultiplex the frame to the appropriate upper-layer protocol. Common values include 0x0800 for IPv4, 0x86DD for IPv6, 0x0806 for ARP, and 0x8847/0x8848 for MPLS. In VLAN-tagged frames, a 4-byte VLAN tag (0x8100 as the TPID) is inserted after the source MAC, and the EtherType of the payload follows the tag.

IEEE 802.3 defines framing that can either carry an EtherType or a length, depending on the format used. In Ethernet II, the 16-bit field conveys the protocol type, while in older 802.3 frames using LLC/SNAP, that field can represent the payload length rather than a type. Some network equipment supports both formats, which can lead to confusion if the term EtherTypein is encountered without context.

In practice, if EtherTypein appears in documentation, it most likely refers to EtherType (the protocol-indication field in Ethernet frames) or to a misnamed/brand-specific concept. There is no widely adopted standard named EtherTypein as of the current literature.