page_title: Frame synchronization
section_title: Framing
hierarchical_section_title: Frame synchronization / Framing
caption_attribution_description: English: Frame Synchronized PCM Stream
context_page_description: In telecommunication, frame synchronization or framing is the process by which, while receiving a stream of framed data, incoming frame alignment signals are identified, permitting the data bits within the frame to be extracted for decoding or retransmission.
context_section_description: If the transmission is temporarily interrupted, or a bit slip event occurs, the receiver must re-synchronize.
  The transmitter and the receiver must agree ahead of time on which frame synchronization scheme they will use.
  Common frame synchronization schemes are:
  Framing bit
  A common practice in telecommunications, for example in T-carrier, is to insert, in a dedicated time slot within the frame, a noninformation bit or framing bit that is used for synchronization of the incoming data with the receiver. In a bit stream, framing bits indicate the beginning or end of a frame. They occur at specified positions in the frame, do not carry information, and are usually repetitive.
  Syncword framing
  Some systems use a special syncword at the beginning of every frame.
  CRC-based framing
  Some telecommunications hardware uses CRC-based framing.
caption: Frame synchronized PCM stream — telemetry application
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