In telecommunications, a frame is a packet which has been encoded for transmission over a particular link.

How framing works

This process involves, at a minimum, adding delimiters to distinguish the packet from dead air, address and control fields specific to the link, and checksums to detect errors.

• Sometimes the address, control, and checksum fields from the higher-level protocol are used directly.

A multiplex interpretation of 'Frames'

Frame may also refer to the way a multiplexer divides the underlying communication channel so that it can be used simultaneously for more than one transmission. Notionally, each frame is a slot which could be filled by a transmitted packet. In these schemes, not all frames are necessarily in use at once.

• In the multiplex structure of pulse-code modulation (PCM) systems, a frame is a set of consecutive time slots in which the position of each digit can be identified by reference to a frame-alignment signal. (This signal does not necessarily occur in each frame.)

• In a time-division multiplexing (TDM) system, a frame is a repetitive group of signals resulting from a single sampling of all channels. The term in-frame is used to indicate that a time-division multiplexer is properly synchronized with the demultiplexer on the other end of the link, so that (barring in-flight data corruption) packets will be properly received.

Telecommunications stubs

Trama de red | Trame (informatique) | Ethernet#Frame | Trama