802.1Q Vlan, ¾ Link Types of ports | TP-Link TL-SG3424P guide

packets of different VLANs. The switch can analyze the received untagged packets on the port and match the packets with the MAC VLAN, Protocol VLAN and 802.1Q VLAN in turn. If a packet is matched, the switch will add a corresponding VLAN tag to it and forward it in the corresponding VLAN.

6.1 802.1Q VLAN

VLAN tags in the packets are necessary for the switch to identify packets of different VLANs. The switch works at the data link layer in OSI model and it can identify the data link layer encapsulation of the packet only, so you can add the VLAN tag field into the data link layer encapsulation for identification.

In 1999, IEEE issues the IEEE 802.1Q protocol to standardize VLAN implementation, defining the structure of VLAN-tagged packets. IEEE 802.1Q protocol defines that a 4-byte VLAN tag is encapsulated after the destination MAC address and source MAC address to show the information about VLAN.

As shown in the following figure, a VLAN tag contains four fields, including TPID (Tag Protocol Identifier), Priority, CFI (Canonical Format Indicator), and VLAN ID.

Figure 6-2 Format of VLAN Tag

（1） TPID: TPID is a 16-bit field, indicating that this data frame is VLAN-tagged. By default, it is 0x8100.

（2） Priority: Priority is a 3-bit field, referring to 802.1p priority. Refer to section “QoS & QoS profile” for details.

（3） CFI: CFI is a 1-bit field, indicating whether the MAC address is encapsulated in the standard format in different transmission media. This field is not described in detail in this chapter.

（4） VLAN ID: VLAN ID is a 12-bit field, indicating the ID of the VLAN to which this packet belongs. It is in the range of 0 to 4,095. Generally, 0 and 4,095 is not used, so the field is in the range of 1 to 4,094.

VLAN ID identifies the VLAN to which a packet belongs. When the switch receives an un-VLAN-tagged packet, it will encapsulate a VLAN tag with the default VLAN ID of the inbound port for the packet, and the packet will be assigned to the default VLAN of the inbound port for transmission.

In this User Guide, the tagged packet refers to the packet with VLAN tag whereas the untagged packet refers to the packet without VLAN tag, and the priority-tagged packet refers to the packet with VLAN tag whose VLAN ID is 0.

¾Link Types of ports

When creating the 802.1Q VLAN, you should set the link type for the port according to its connected device. The link types of port including the following three types:

（1） ACCESS: The ACCESS port can be added in a single VLAN, and the egress rule of the port is UNTAG. The PVID is same as the current VLAN ID. If the ACCESS port is added to another VLAN, it will be removed from the current VLAN automatically.

TL-SG3424P specifications

The TP-Link TL-SG3424P is a high-performance managed switch designed to meet the needs of small to medium-sized businesses. Offering 24 Gigabit Ethernet ports, this device is an ideal solution for improving network efficiency and ensuring seamless data transfer across multiple devices. The switch not only facilitates connectivity but also provides robust management features to enhance the performance and security of your network.

One of the standout features of the TL-SG3424P is its Power over Ethernet (PoE) capability, which allows it to deliver power and data over the same Ethernet cable. This feature is particularly beneficial for deploying devices such as IP cameras, VoIP phones, and wireless access points without the need for additional power sources. With a total power budget of 250W, the TL-SG3424P can support a diverse range of PoE devices, providing convenience and flexibility in deployment.

In terms of management, the TL-SG3424P offers a user-friendly web interface, allowing network administrators to configure and monitor the switch with ease. It supports advanced Layer 2 features, including VLANs, Quality of Service (QoS), and Link Aggregation. These features enhance network performance by optimizing traffic flow and prioritizing essential applications. The switch also includes comprehensive security features, such as Port Security and Access Control Lists (ACL), which help protect against unauthorized access and ensure data integrity.

The build quality of the TL-SG3424P is robust, designed to handle demanding network environments. It includes a fanless design, which ensures silent operation, making it suitable for office environments where noise can be a distraction. The metal chassis is durable and built for longevity, ensuring that the device will withstand rigorous usage over time.

Furthermore, the TL-SG3424P supports SNMP (Simple Network Management Protocol), allowing for centralized network monitoring and management. This makes it easier for IT teams to keep track of network health and performance, enabling timely interventions when necessary.

In conclusion, the TP-Link TL-SG3424P is a versatile and powerful managed switch that combines PoE capabilities with advanced network management features, making it a perfect choice for businesses looking to upgrade their network infrastructure. With its reliable performance and robust features, it provides an excellent solution for enhancing productivity and connectivity in any office setting.

TP-Link TL-SG3424P manual 802.1Q Vlan, ¾ Link Types of ports

Models: TL-SG3424P