Difference Between Trunk Port and Access Port

Lets talk about Access Port and Trunk port one by one and will followed by the difference between them.

What is Access Port ?

When you configure a port in access mode, you can specify which VLAN will carry the traffic for that interface. If you do not configure the VLAN for a port in access mode, or an access port, the interface carries traffic for the default VLAN (VLAN1).

You can change the access port membership in a VLAN by specifying the new VLAN. You must create the VLAN before you can assign it as an access VLAN for an access port. If you change the access VLAN on an access port to a VLAN that is not yet created, the system will shut that access port down. If an access port receives a packet with an 802.1Q tag in the header other than the access VLAN value, that port drops the packet without learning its MAC source address.

What is Trunk Port ?

A trunk is a point-to-point link between the device and another networking device. Trunks carry the traffic of multiple VLANs over a single link and allow you to extend VLANs across an entire network. To correctly deliver the traffic on a trunk port with several VLANs, the device uses the IEEE 802.1Q

encapsulation (tagging) method that uses a tag that is inserted into the frame header. This tag carries information about the specific VLAN to which the frame and packet belong. This method allows packets that are encapsulated for several different VLANs to traverse the same port and maintain traffic separation between the VLANs. The encapsulated VLAN tag also allows the trunk to move traffic end-to-end through the network on the same VLAN.

Access Port Vs. Trunk Port ?

Here is the difference between Access and the trunk port shown below

Access port

It supports a single VLAN
It connects end devices to the network.
It uses only one encapsulation protocol – IEEE 802.1Q
It does not support VLAN tagging.
Traffic is part of the same broadcast domain.
Voice VLAN is the feature that is supported in Access Port.
It supports untagged frames.

Trunk Port

It supports multiple VLANs.
Multiple VLANs are allowed to traverse and add tags.
It connects switches or routers together.
It uses encapsulation protocol – IEEE 802.1Q and ISL
It supports VLAN tagging.
It allows segmentation into separate broadcast domains.
Voice VLAN is a feature that is not supported in Trunk Port.
It supports tagged frames

Difference Between Trunk Port and Access Port