Difference Between Trunk Port and Access Port

When it comes to networking, two terms that are “access port” and “trunk port" arises in our mind. They both sound familiar but both of these types have different functions. While commonly associated with Cisco, access ports and trunk ports are standard networking concepts utilized across various network equipment vendors. Access Port is a port that is assigned to a single VLAN whereas Trunk Port is a port that is assigned to multiple VLANs. Let's see in what aspects they differ.

What is a Trunk Port?

A trunk port is a type of port used to connect switches or routers, transmitting data from multiple VLANs simultaneously. It uses tagging to ensure data reaches the correct destination, offering higher bandwidth and lower latency. Operating at layer 2 of the OSI model, it utilizes IEEE 802.1Q encapsulation for traffic delivery.

Advantages

1. It offers higher bandwidth and lower latency.
2. It sends all signals across a single trunk link which is for each switch or router.
3. It can carry traffic for several VLANs simultaneously. 

Disadvantage

1. It is quite complex to set up when compared with the Access port.

What is an Access Port?

An access port connects virtual machines to a switch or VLAN, transmitting data within a single VLAN. While it avoids signal issues, it may not be efficient for complex networks, though it can be optimized as a host port.

Advantages

1. It sends and receives frames that aren’t tagged.
2. There are no signal issues in the access port as the frame remains in a single VLAN.
3. To decrease the time it takes the designated port to begin to forward packets, use the host port.

Disadvantages

1. It can carry traffic for only one VLAN.
2. Only an end station can be set as a host port.

Difference between Trunk Port and Access Port

The main and basic use of these both the trunk port and access port is to move traffic between VLANs. The user can carry more than one VLAN traffic from one switch to another switch with Trunk Port whereas data is transmitted simultaneously with Access Port. Both ports have their own pros and cons and it all depends on the user to select which port according to their own requirement.

Conclusion

Traffic between VLANs must pass through both trunk and access ports. Trunk ports facilitate the transfer of multiple VLAN traffic streams across switches, while access ports enable data transmission within a specific VLAN. Each port has its own strengths and limitations, with the choice depending on the user's specific needs.