EtherIP (RFC 3378) - Definition from the Hotspot Shield Glossary
EtherIP is a standard protocol defined by RFC 3378 and is used for the tunneling of Ethernet frames across an IP internet. This tunneling process will occur at layer three of the OSI reference model when MAC frames are not IP or when the required routing information is obscured by encryption.
EtherIP can be implemented either by a single device to establish an Ethernet tunnel, or as a bridge to providing tunneling services for all the devices connected to a LAN. An EtherIP datagram is split into two sections - An 8bit header, and an encapsulated frame; the header identifies the EtherIP version and details, and the encapsulated frame contains variable length data.