The understanding of VLAN, trunk, and hybrid in the entry level engineer entering the threshold of the network

Any successful person is standing on the shoulders of giants to succeed, and I have not succeeded, and then I excerpt from an article and add some of their own experience to write about the VLAN, trunk and hybrid the difference:

Ethernet ports have 3 types of links: access, trunk, Hybird
An access type port can only belong to 1 VLANs for connecting to a computer port;

Trunk type port can allow multiple VLANs through, can receive and send multiple VLAN packets, generally used for the connection between switches;

The hybrid type port can allow multiple VLANs to pass through, can receive and send multiple VLAN messages, can be used for inter-switch connections and can also be used to connect user computers.

The hybrid port and trunk port handle the same way of thinking when receiving data, the only difference is that when sending data: The hybrid port can allow multiple VLAN packets to be sent without tagging, while the trunk port allows only the default VLAN packets to be sent without marking.

Default VLAN:

The access port only belongs to 1 VLANs so its default VLAN is that it resides in a VLAN without setting;

The hybrid port and trunk ports belong to multiple VLANs, so you need to set the default VLAN ID. By default the hybrid port and trunk port default VLAN is VLAN 1;

If the port default VLAN ID is set, the message is forwarded to the port that belongs to the default VLAN when the port is received without the VLAN tag message, and when the port sends a VLAN tag message, the Packet VLAN tag is removed if the message VLAN ID and port default VLAN ID are the same. , and then send the message.

Note: The default VLAN for Huawei switches is known as "Pvid VLAN" for Cisco switch default VLAN is called "Native VLAN"

Switch interface Access data processing process:
Acess Port Ticker: Receive a message to determine if there is VLAN information: if not, the upper port Pvid and exchange, forwarding, if there is a direct discard (default) acess port text: The message VLAN information stripping directly sent out

Trunk Port Ticker: received a message to determine if there is VLAN information: if there is no port PVID and Exchange forwarding, if there is a Judge Vland ID is within the allowable range of the trunk, if within the scope of the forwarding, otherwise discarded

Trunk Port transmitter: Compare Port Pvid and will send message VLAN information if the two are equal then the VLAN information is stripped and sent, if not equal, sent directly

Hybrid Port Ticker: received a message to determine if there is VLAN information: If not, hit the upper port PVID and Exchange forwarding. If any, determine whether the hybrid port allows the VLAN data to enter: if it can be forwarded, otherwise discarded (at this time the port on the UNTAG configuration is not considered, UNTAG configuration only to send the message when the role)

Hybrid Port Transmitter text:

1, judge the VLAN on this port property (disp Erface can see the port to which VLAN is UNTAG which VL
An IS tag)

2, if the UNTAG is stripped VLAN information and then send if it is the tag directly sent

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In fact, we have a switch to send and receive data direction is not clear: because an interface in the receipt of data, while it is also external data, we can easily send and receive an interface to confuse.

This article is from the "Gossip, meditation" blog, please be sure to keep this source http://yanhuasanyue.blog.51cto.com/9005517/1762507

The understanding of VLAN, trunk, and hybrid in the entry level engineer entering the threshold of the network