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frame

The unit a local network link (Ethernet or Wi-Fi) actually sends, carrying a packet inside.

A frame is the link-layer unit -- an Ethernet or 802.11 frame -- with source and destination MAC addresses, which carries one IP packet across one hop. (A UART frame from embedded-systems is a different thing: one character on a serial line.)

Examples

  • The sensor's IP packet travels inside a frame whose header names destination and source MACs, such as the sensor's 24:6f:28:aa:bb:cc.

  • A frame ends with a 4-byte frame check sequence that lets the receiver throw away a frame damaged on the link.

See also

MAC address packet encapsulation
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