Ethernet refers to one of several IEEE standards for link-level frame transmission. Some of the main Ethernet standards include:
Common to all these frame types are the following elements:
If the payload is less the 46 bytes, it is padded with zeros. In Ethernet II, the length field is interpreted as a type field, indicating the nature of the layer three payload. 802.3 cannot indicate type, and can only carry IPX at layer three.
Ethernet was originally engineered as a local area, multi-access protocol with collision detection. With the widespread introduction of switched networks, collisions have declined in prevalence and Ethernet speeds have increased. Through encapsulation by wide area protocols such as MPLS or Packet over SONET, Ethernet is now found even on wide area networks.
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