Store Forward | Allied Telesis AT-FS750/24POE specs

Chapter 1: Overview

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Back Pressure and Flow Control

end node can receive or transmit data, but not both simultaneously, the end node is operating in what is referred to as half-duplex mode. If an end node can both receive and transmit data simultaneously, the end node is said to be operating in full-duplex mode. Naturally, an end node capable of operating in full-duplex can handle data much faster than an end node that can only operate in half-duplex mode.

The twisted pair ports on the AT-FS750/24POE Fast Ethernet Smart switch can operate in either half-or full-duplex mode. They are IEEE 802.3u-compliant and you can set them to Auto-Negotiation.

For Auto-Negotiation to operate properly on a switch, the end nodes connected to the switch should also use Auto-Negotiation. If an end node does not have this feature and has a fixed duplex mode of full-duplex, the result will be a duplex mode mismatch between the end node and a switch port. A port on the Fast Ethernet switch connected to an end node with a fixed duplex mode of full-duplex will operate at only half-duplex. This results in the end node using full-duplex and the switch port using half- duplex. This can produce network performance problems. If you encounter this situation, you must configure the port on the end node to use Auto-Negotiation or, if it lacks that feature, to half-duplex.

The switch uses store and forward as the method for receiving and transmitting frames. When a Ethernet frame is received on a switch port, the switch does not retransmit the frame out the destination port until it has received the entire frame and stored the frame in a port buffer. It then examines the frame to determine if it is a valid frame. Invalid frames, such as fragments or runts, are discarded by the switch. This ensures that only valid frames are transmitted out the switch ports and that damaged frames are not propagated on your network.

To maintain the orderly movement of data between the end nodes, an Ethernet switch may periodically need to signal an end node to stop sending data. This can occur under several circumstances. For example, if two end nodes are operating at different speeds, the switch, while transferring data between the end nodes, might need to instruct the faster end node to stop transmitting data to allow the slower end node to catch up. An example of this would be when a server operating at 100 Mbps is sending data to a workstation operating at only 10 Mbps.

How a switch signals an end node to stop transmitting data differs depending on the speed and duplex mode of the end node and switch port. A twisted pair port operating at 100 Mbps and half-duplex mode will stop an end node from transmitting data by forcing a collision. A collision on an Ethernet network occurs when two end nodes attempt to transmit data using the same data link at the same time. A collision causes end nodes to stop sending data. When the switch needs to stop a 100 Mbps, half-duplex end node from transmitting data, it forces a collision on the data link, which stops the end node. When the switch is ready to receive

AT-FS750/24POE specifications

Allied Telesis is renowned for its high-quality networking solutions, and the AT-FS750 series exemplifies this commitment with its robust functionality and advanced features. The AT-FS750/24POE and AT-FS750/48 are two powerful models designed to meet the diverse needs of modern networks, providing reliable connectivity and efficient power management.

The AT-FS750/24POE model is particularly notable for its Power over Ethernet (PoE) capabilities, allowing it to deliver power and data over the same Ethernet cable. This is especially beneficial for deploying devices like IP phones, security cameras, and wireless access points in locations where power sources may be limited. With 24 PoE-enabled ports, the switch can efficiently power multiple devices simultaneously, streamlining installations and reducing clutter.

Conversely, the AT-FS750/48 offers a more extensive configuration with 48 standard Ethernet ports. This model is ideal for larger networks that require seamless connectivity for a higher number of devices. Its robust architecture ensures optimal performance and reliability in demanding environments, making it a preferred choice for enterprises looking to enhance their infrastructure.

A key feature of both models is the Layer 2 switching technology, which ensures high-speed data forwarding and efficient traffic management within the local area network (LAN). This technology supports essential protocols such as VLAN (Virtual Local Area Network) tagging, enabling network segmentation and better security. The switches also boast a high switching capacity, ensuring minimal latency and maximizing throughput for connected devices.

Both AT-FS750 switches are designed with user-friendly management options. They support a web-based interface, simplifying configuration and monitoring tasks for IT staff. Additionally, the switches incorporate SNMP (Simple Network Management Protocol) for streamlined network management, allowing administrators to oversee network performance and troubleshoot issues effectively.

Another notable characteristic is their compact, fanless design, which not only reduces noise but also extends the lifespan of the equipment due to minimized thermal stress. The rugged casing ensures durability, making them suitable for various environments, from small offices to large enterprise networks.

In summary, the Allied Telesis AT-FS750/24POE and AT-FS750/48 switches provide a versatile solution for organizations seeking reliable and efficient networking capabilities. With PoE support, comprehensive management features, and robust performance, these switches are well-suited to meet the evolving demands of today's networking landscape.