Enterprise networks continue to expand, growing more
versatile and complex. Devices once considered peripherals—wireless access
points, security cameras, intelligent building systems and voice-over-IP (VoIP)
phones—are now important network assets. As more devices are added, the cabling
infrastructure needed to support them will have to expand and the option to power
them over structured cabling becomes more attractive.
Over the last decade, Power over Ethernet
(PoE) has emerged as a key powering strategy allowing network managers,
installers and integrators to use structured cabling to provide both power and
data to many of their network devices. The original PoE standard, IEEE 802.3af,
limited the technology to devices requiring less than 12.95 watts of power.
Less than three years after the first standard was published, an initiative was
started to implement updates addressing the growing demand for more power.
The revised PoE standard IEEE 802.3at, also known as PoE
Plus or PoE+, was adopted in 2009 and raised the PoE power supply to 25.5 watts.
Since then, the industry’s interest and demand for higher power PoE solutions
continues to snowball. The IEEE PoE Task
Force is already well into the development of the next evolution of the
standard. The new standard, to be named IEEE 802.3bt, is intended to deliver up
to 49 watts of power to PoE-enabled devices.
CommScope has developed a white paper to provide customers
information on laying the groundwork for this higher level of PoE. In this
white paper CommScope recommends the following for additional margin and
flexibility of 4-pair PoE:
6A cabling: To help minimize thermal loading and its associated costs,
CommScope recommends running Category 6A cabling to each powered device, preferably
using a zone cabling architecture.
of power delivery: In order to accommodate future capacity upgrades and
ensure diversity in power delivery, it is also suggested that network managers
plan for at least two runs of Category 6A cabling per powered device to each
zone distributor. This will allow each device to be powered from two different
- Reliability testing: If connectors are unplugged under load, an inductive current is created within the connector that may spark at one or more contact surfaces, causing the surfaces to corrode. It is recommended that connecting hardware be qualified to support PoE and 4-pair PoE applications by using the test schedules in IEC 60512-99-001.
If you would like to download this white paper, click here
and look on the right-hand side of the web page under “Related Resources.”