Framing in data transmission

The transmitter provides a method to tell the receiver where the data block starts and ends :

The advantage of using frames is that the data is divided into recoverable blocks and it is easy to check whether these blocks are damaged . A fault in the transmission process will destroy some frames . Only the lost frames, not the whole set of data, need to be retransmitted .“ Error detection and correction ” It discusses the detection and correction of errors .

A frame is a series of standardized data bits , It is the basic unit of network communication . Its general format is a header and a data payload area . Although the data area is variable , The size of the frame is usually fixed . Most data link networks use frames of variable size , This frame has advantages ( Use the network more effectively ) There are also shortcomings. ( Unpredictable information flow and inability to provide high-quality services ).

Ethernet frame (IEEE 802.3) yes OSI Reference model data link layer encapsulation , The packet of network layer is added with frame header and frame footer , Constitute a data frame that can be recognized by the data link layer . Pictured F-16 Shown , It can hold up to l500Byte The data of . Frame includes title 、 Tail bytes and encapsulated data . The information in the title is additional data that must be transmitted , This increases the cost .