Overview Ethernet Interface

Ethernet interface includes L2 Ethernet interface and L3 Ethernet interface.

L2 Ethernet interface, also called port, is one physical interface. It works at layer 2 in the OSI reference model-data link layer. It is mainly used to execute two basic operations:

• Data frame forwarding: According to the MAC address (that is physical address) of the data frame, forward the data frame. L2 Ethernet interface can only perform the L2 switching forwarding for the received packets, that is, can only receive and send the packets whose source IP and destination IP are at the same segment.
• MAC address learning: Construct and maintain the MAC address table, used to support forwarding the data frames.

L3 Ethernet interface is one physical interface. It works at layer 3 in the OSI reference model-data link layer. It is mainly used to execute two basic operations:

• Packet forwarding: Perform the route forwarding of the packets according to the IP (Internet Protocol) address (that is net5work address) of the packet. L3 Ethernet interface can only perform the L3 route forwarding for the received packet, that is, can receive and send the packet whose source IP and destination IP are in different segments.

According to the maximum rate supported by the Ethernet interface, the Ethernet interface type can be divided to the following:

• fastethernet: 100M Ethernet interface can be abbreviated as Fa, such as fastethernet0/1 or Fa0/1;
• gigabitethernet: 1000M Ethernet interface, can be abbreviated as Gi, such as gigabitethernet0/25 or Gi0/25;
• tengigabitethernet: 10G Ethernet interface, can be abbreviated as Te, such as tengigabitethernet1/1 or Te1/1.
• 25ge: 25G Ethernet interface
• 40ge: 40G Ethernet interface
• 100ge: 100G Ethernet interface