Summary of 802.3 frames of forward code

 

Summary of 802.3 frames of forward code

Let's first look at a frame structure.

We can easily understand and even capture packets from the data link layer, but the front guide code is not so easy to see its real structure.

The authorization code encapsulated by the physical layer and the starting delimiters of the frame are composed of 8-byte fixed values.

The fixed binary value is as follows:

10101010 10101010 10101010 10101010 10101010 10101010 10101010

Hexadecimal representation:

AA AB

The first 7 bytes are used to adjust the clock and keep the clock synchronized with the sending end.

The next byte indicates that '1' will be the starting position of the frame and the destination address will be read.

This article is from the "Yu zichen-IT Road" blog