AT-GS900/8POE Gigabit Ethernet Switch Installation Guide

Note

Power is supplied to the powered devices in the order that the ports are connected or on a first-come-first-served basis until the 65 watt limit is reached. If the switch is power cycled after the PoE devices are connected to the switch ports, the power is supplied to ports 1 through 8 in that order.

Table 5. IEEE 802.3af Class vs. Power Levels

 

 

Minimum Power

Maximum Power

Class

Usage

Levels Output at

Levels Output at

 

 

the PSE

the PD

 

 

 

 

 

 

 

 

0

Default

15.4W

0.44W to 12.95W

 

 

 

 

1

Optional

4.0W

0.44W to 3.84W

 

 

 

 

2

Optional

7.0W

3.84W to 6.49W

 

 

 

 

3

Optional

15.4W

6.49W to 12.95W

 

 

 

 

A port connected to a network node that is not a powered device (that is, a device that receives its power from another power source) functions as a regular Ethernet port, without PoE. The PoE feature remains enabled on the port but no power is delivered to the device.

Implementation A standard Ethernet twisted pair cable contains four pairs of strands for a total of eight strands. 10/100 Mbps network traffic requires only four strands (1, 2, 3, and 6), leaving four strands in the cable unused (4, 5, 7, and 8). 1000 Mbps network traffic uses all eight strands.

The PoE standard, IEEE 802.3af, describes two alternative ways for delivering power to a powered device (PD) over twisted pair cabling. Alternative A uses the same strands that carry the network traffic.

Alternative B uses the spare strands. The PoE implementation on the AT-GS900/8POE Gigabit Ethernet switch is Alternative A, where power is transmitted over strands 1, 2, 3, and 6.

PD’s that comply with the IEEE 802.3af standard typically support both power delivery methods. If a PD is compliant with the standard, it should be able to receive its power from the switch while using either a straight or cross-over cable. The PoE feature on the AT-GS900/8POE Gigabit Ethernet switch should also work with most legacy PD’s as long as the device can be powered on pins 1, 2, 3, and 6. A legacy device is a node that was manufactured before the IEEE 802.3af standard was completed and, consequently, may not adhere to the standard. If this is the case, a cross-over (MDI-X) cable may be needed to insure that the DC polarity is correct.

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Allied Telesis GS900/8POE manual Minimum Power Maximum Power Class

GS900/8POE specifications

The Allied Telesis GS900/8POE is a versatile and robust switch designed for small to medium-sized enterprises that require reliable network performance combined with power over Ethernet (PoE) capabilities. As part of the GS900 series, this switch offers a range of features, technologies, and characteristics that cater to modern networking demands.

One of the main features of the GS900/8POE is its eight 10/100/1000BASE-T Ethernet ports, which enable seamless connectivity for a variety of devices. Each port is equipped with Power over Ethernet capabilities, allowing the switch to deliver up to 15.4 watts of power per port. This is particularly beneficial for powering devices such as IP cameras, wireless access points, and VoIP phones without the need for additional power sources, minimizing installation costs and clutter.

The GS900/8POE also supports advanced Layer 2 switching capabilities, including VLAN (Virtual Local Area Network) support, which enhances network segmentation and security. By allowing administrators to create isolated networks within a larger network, VLANs reduce broadcast traffic and improve overall performance. Additionally, the switch supports Quality of Service (QoS) features, ensuring that time-sensitive applications, such as video streaming and voice communications, receive priority over less critical data.

Another noteworthy characteristic of the GS900/8POE is its fanless design, which makes it ideal for environments where noise levels need to be kept to a minimum. This design approach not only enhances the aesthetics of the deployment area but also increases reliability by reducing moving parts that could potentially fail.

Security is also a significant focus in the GS900/8POE's design, with features like MAC address filtering and DHCP snooping to protect against unauthorized access and potential network attacks. These safeguards ensure that network administrators can maintain control over connected devices and mitigate risks associated with security breaches.

In summary, the Allied Telesis GS900/8POE switch is a feature-rich solution that meets the demands of modern networks. Its PoE capabilities, advanced Layer 2 features, fanless operation, and robust security measures make it an excellent choice for businesses looking to expand their network infrastructure while keeping operational efficiency and reliability at the forefront. Whether used in a small office setting or for branch locations, the GS900/8POE provides a compelling balance of performance and functionality.