Chapter 18: Setting LLDP and LLDP-MED

Overview

Link Layer Discovery Protocol (LLDP) and Link Layer Discovery Protocol for Media Endpoint Devices (LLDP-MED) allow Ethernet network devices such as switches and routers to receive and/or transmit device-related information to directly connected devices on the network that are also using the protocols, and to store the information that is learned about other devices. The data sent and received by LLDP and LLDP-MED are useful for many reasons. The switch can discover other devices directly connected to it. Neighboring devices can use LLDP to advertise some parts of their Layer 2 configuration to each other, enabling some types of misconfiguration to be more easily detected and corrected.

LLDP is a “one hop” protocol. LLDP information can only be sent to and received by devices that are directly connected to each other, or connected via a hub or repeater. Devices that are directly connected to each other are called neighbors. Advertised information is not forwarded on to other devices on the network. In addition, LLDP is a one-way protocol. That is, the information transmitted in LLDP advertisements flows in one direction only, from one device to its neighbors, and the communication ends there. Transmitted advertisements do not solicit responses and received advertisements do not solicit acknowledgements. LLDP cannot solicit any information from other devices. LLDP operates over physical ports only. For example, it can be configured on switch ports that belong to static port trunks or LACP trunks, but not on the trunks themselves, and on switch ports that belong to VLANs, but not on the VLANs themselves.

Each port can be configured to transmit local information, receive neighbor information, or both. LLDP transmits information as packets called LLDP Data Units (LLDPDUs). An LLDPDU consists of a set of Type-Length- Value elements (TLV), each of which contains a particular type of information about the device or port transmitting it.

A single LLDPDU contains multiple TLVs. TLVs are short information elements that communicate complex data, such as variable length strings, in a standardized format. Each TLV advertises a single type of information, such as its device ID, type, or management addresses.

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AT-9000/52, AT-9000/28SP, AT-9000/28 specifications

The Allied Telesis AT-9000/28 is a versatile and robust network switch designed for organizations seeking to enhance their networking capability. This Layer 2 managed switch delivers a high degree of performance and reliability, making it an ideal choice for businesses that require a seamless network experience.

One of the main features of the AT-9000/28 is its 28 ports, which include 24 Fast Ethernet ports and 4 Gigabit Ethernet uplink ports. This allows for flexible network configuration and scalability, accommodating both wired and wireless devices efficiently. The switch also supports auto-negotiation and auto-MDI/MDI-X, which simplifies installation and connectivity by automatically detecting and configuring the appropriate settings.

The AT-9000/28 employs advanced switching technologies, such as IEEE 802.1Q VLAN tagging, which enables the segregation of traffic for improved security and performance. This feature is crucial for businesses that require data isolation between different departments or user groups. In addition, the switch supports quality of service (QoS) protocols, allowing for traffic prioritization. This is particularly beneficial for organizations that handle multimedia applications or VoIP services that demand reliable bandwidth.

Another significant characteristic of the AT-9000/28 is its support for port mirroring. This capability is essential for network monitoring and troubleshooting, as it allows administrators to track and analyze network traffic efficiently. Furthermore, the switch supports multiple user authentication methods, including RADIUS and TACACS+, thus enhancing network security.

The AT-9000/28 is built with energy efficiency in mind, featuring Energy Efficient Ethernet (EEE) technology. This reduces power consumption during periods of low traffic without compromising performance, which aids in lowering overall operational costs.

In terms of management, the AT-9000/28 offers versatile management options, including a web-based GUI, Command Line Interface (CLI), and SNMP support. This flexibility enables network administrators to configure, monitor, and troubleshoot the switch easily.

Overall, the Allied Telesis AT-9000/28 is a reliable switch well-suited for a variety of network environments. Its combination of performance, security features, and energy efficiency makes it an excellent choice for organizations looking to optimize their network infrastructure. With robust capabilities and advanced technologies, the AT-9000/28 stands out as a valuable addition to any networking setup.