Network Technology Learning Note 2-data link layer

The data link layer can be divided into the LLC layer (Logical Link Layer) and MAC layer (media access layer ). The LLC layer provides high-level interfaces and controls the underlying layer (error and traffic control)
Traffic control: throttling Window Flow Control (based on the returned response, the recipient's receiving capacity is determined to adjust its own rate)
The MAC layer completes the channel occupation problem of the sender.
Channel occupation method:
Competing for contention Ethernet to see who is pushing faster advantages: simple, easy to implement, low cost disadvantages: easy to cause congestion
Token token passing the token frame of the Ring Network. Whoever gets the frame occupies a high channel cost, making it difficult to implement
It is common to use polling point to multiple points.

Currently, the Ethernet basic unified data link layer is widely used.

MAC address 12-bit hexadecimal number
ARP Protocol

ARP-A lists the MAC addresses of communication machines. In fact, it displays the data in the buffer zone.