EtherTypekenttää

EtherTypekenttää refers to the EtherType field within an Ethernet frame. This field is crucial for network layer demultiplexing, allowing the receiving network interface card (NIC) to determine the protocol encapsulated within the payload of the Ethernet frame. The EtherType field is a 16-bit value. When the value is 1500 or less, it is interpreted as the Length field, indicating the number of bytes in the payload for the IEEE 802.3 standard. However, for protocols that use the Ethernet II framing (also known as DIX framing), values greater than 1500 are interpreted as the EtherType, signifying the protocol being carried. Common EtherType values include 0x0800 for Internet Protocol version 4 (IPv4), 0x86DD for Internet Protocol version 6 (IPv6), and 0x0806 for the Address Resolution Protocol (ARP). Network devices inspect this field to efficiently pass the frame to the correct protocol handler, streamlining network communication and ensuring data is processed by the appropriate software stack. The assignment of EtherType values is managed by the Institute of Electrical and Electronics Engineers (IEEE).