Power over Ethernet (PoE) is a technology that allows for the
transmission of electrical power and data over a standard Ethernet cable.
This eliminates the need for separate power cables and simplifies the
installation of network devices, such as IP phones, wireless access points,
and security cameras. PoE technology is widely used in both small and
large-scale network deployments.
There are two main PoE methods: Standard PoE and PoE+. In this article, we
will discuss these two PoE methods in detail.
Standard PoE: Standard PoE, also known as IEEE 802.3af, was introduced in
2003 and provides up to 15.4 watts of power to network devices. This is
sufficient to power most IP phones, wireless access points, and small
security cameras. Standard PoE uses two pairs of wires in an Ethernet cable
to transmit power to the device. The power is transmitted along with the
data in a single cable, reducing the number of cables needed to connect a
device to the network.
PoE+: PoE+, also known as IEEE 802.3at, was introduced in 2009 and provides
up to 30 watts of power to network devices. This is double the power
provided by standard PoE and is sufficient to power larger devices such as
pan-tilt-zoom (PTZ) cameras, video conferencing systems, and access points
with multiple radios. PoE+ uses all four pairs of wires in an Ethernet cable
to transmit power to the device, allowing for more efficient power
delivery.
Also, Check: Top 50+ Cisco VoIP IPT and above Level Interview Questions and Answers
It is important to note that not all network devices are compatible with
PoE technology. Devices must have built-in PoE support or use an external
PoE splitter to convert PoE power to the appropriate voltage for the
device.
In addition, PoE technology has evolved over time, and newer PoE standards,
such as IEEE 802.3bt, can provide even higher levels of power to network
devices. IEEE 802.3bt, also known as PoE++, can provide up to 90 watts of
power, making it suitable for powering devices such as thin clients, digital
signage, and even small laptops.
In conclusion, PoE technology provides a simple and efficient way to power
network devices over a standard Ethernet cable. Standard PoE and PoE+ are
the two main PoE methods and provide different levels of power to network
devices. As the demand for higher-powered devices continues to grow, newer
PoE standards such as PoE++ will become increasingly important in network
deployments.