AT-GS950/48 Gigabit Ethernet WebSmart Switch Installation Guide

Ethernet Switching Basics

MAC Address Table

An Ethernet switch interconnects network devices, such as workstations, printers, routers, and other Ethernet switches, so that they can communicate with each other by sending and receiving Ethernet frames.

Every hardware device on your network has a unique MAC address. This address is assigned to the device by the device’s manufacturer. For example, when you install a Network Interface Card (NIC) in a computer so that you can connect it to the network, the NIC already has a MAC address assigned to it by its manufacturer.

The MAC address table in the AT-GS950/48 Gigabit Ethernet Smart switch can store up to 8K MAC addresses. The switch uses the table to store the MAC addresses of the network end nodes connected to the ports, along with the port number on which each address was learned.

A switch learns the MAC addresses of the end nodes by examining the source address of each packet received on a port and adding. It adds the address and port on which the packet was received into the MAC table if the address does not already exist. The result is a table that contains all the MAC addresses of the network devices connected to the switch’s ports, and the port number where each address was learned.

When the switch receives a packet, it also examines the destination address and, by referring to its MAC address table, determines the port on which the destination end node is connected. Then it forwards the packet to the appropriate port and on to the end node. This increases network bandwidth by limiting each frame to the appropriate port when the intended end node is located, freeing the other switch ports for receiving and transmitting data.

If the switch receives a packet with a destination address that is not in the MAC address table, it floods the packet to all of the ports on the switch. If the ports have been grouped into virtual LANs, the switch floods the packet only to those ports which belong to the same VLAN as the port on which the packet was received. This prevents packets from being forwarded into inappropriate LAN segments, decreasing network security. When the destination end node responds, the switch adds its MAC address and port number to the table.

If the switch receives a packet with a destination address that is on the same port on which the packet was received, it discards the packet without forwarding it on to any port. Since both the source end node and the destination end node for the packet are located on the same port on the switch, there is no reason for the switch to forward the packet.

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Allied Telesis AT-GS950/48 manual Ethernet Switching Basics, MAC Address Table

AT-GS950/48 specifications

The Allied Telesis AT-GS950/48 is a robust and high-performance managed Gigabit Ethernet switch designed to meet the demands of modern networks. Ideal for small to medium-sized businesses and enterprise environments, this switch delivers flexible, reliable, and high-speed connectivity while ensuring ease of management.

One of the standout features of the AT-GS950/48 is its offering of 48 Gigabit Ethernet ports, allowing for extensive connectivity options. These ports support auto-negotiation and can automatically detect the highest speed supported by connected devices, ensuring optimal performance. The inclusion of 4 additional SFP (Small Form-factor Pluggable) ports enhances the flexibility of the network design. These SFP ports enable fiber connections, making it easy to extend the network over longer distances or connect to different types of media.

The switch supports advanced Layer 2 features, including VLAN (Virtual Local Area Network) support, which allows network administrators to segment network traffic for enhanced security and performance. The AT-GS950/48 also incorporates features such as Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP) that prevent loops in the network and promote redundancy, ensuring uninterrupted service even in complex networking environments.

Additionally, the AT-GS950/48 supports Power over Ethernet (PoE), which enables the switch to deliver power to connected devices such as IP cameras, VoIP phones, and wireless access points through the Ethernet cable, reducing the need for additional power sources. This PoE capability allows for easier installation and flexibility in deploying network devices.

Allied Telesis places a strong emphasis on security, and the AT-GS950/48 reflects this commitment with features like IEEE 802.1X authentication, which secures network access by allowing only authorized users to connect. The switch also provides access control lists (ACLs) to enhance security by filtering traffic based on various criteria.

With built-in web-based management, the AT-GS950/48 enables administrators to easily configure, manage, and monitor the switch through an intuitive interface. It also supports SNMP (Simple Network Management Protocol) for integration into existing network management systems.

In summary, the Allied Telesis AT-GS950/48 combines high port density, advanced networking features, power delivery capabilities, and robust security measures, making it an excellent choice for organizations looking to build a resilient and efficient network infrastructure.