zTx&Rx: the port can both transmit and receive LLDPDUs.

zRx_Only: the port can receive LLDPDUs only.

zTx_Only: the port can transmit LLDPDUs only.

zDisable: the port cannot transmit or receive LLDPDUs.

2)LLDPDU transmission mechanism

zIf the ports are working in TxRx or Tx mode, they will advertise local information by sending LLDPDUs periodically.

zIf there is a change in the local device, the change notification will be advertised. To prevent a series of successive LLDPDUs transmissions during a short period due to frequent changes in local device, a transmission delay timer is set by network management to ensure that there is a defined minimum time between successive LLDP frame transmissions.

zIf the LLDP admin status of the port is changed from Disable/Rx to TxRx/Tx, the Fast Start Mechanism will be active, the transmit interval turns to be 1 second, several LLDPDUs will be sent out, and then the transmit interval comes back to the regular interval.

3)LLDPDU receipt mechanism

When a port is working in TxRx or Rx mode, the device will check the validity of the received LLDPDUs and the attached TLVs, save this neighbor information to the local device and then set the aging time of this information according to the TTL value of TTL (Time To Live) TLV. Once the TTL is 0, this neighbor information will be aged out immediately.

The aging time of the local information in the neighbor device is determined by TTL. Hold Multiplier is a multiplier on the Transmit Interval that determines the actual TTL value used in an LLDPDU. TTL = Hold Multiplier * Transmit Interval.

¾TLV

TLV refers to Type/Length/Value and is contained in a LLDPDU. Type identifies what kind of information is being sent, Length indicates the length of information string in octets and Value is the actual information to be sent. The basic TLV Format is shown as follows:

Each TLV is identified by a unique TLV type value that indicates the particular kind of information contained in the TLV.

The following table shows the details about the currently defined TLVs.

TLV type

TLV Name

Description

Usage in

 

 

 

LLDPDU

 

 

 

 

0

End of LLDPDU

Mark the end of the TLV sequence in

Mandatory

 

 

LLDPDUs. Any information following an End Of

 

 

 

LLDPDU TLV shall be ignored.

 

 

 

 

 

 

 

196

 

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TP-Link TL-SG3424P manual ¾ TLV, TLV type TLV Name Description Usage

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.