Power over Ethernet is a technology for wired Ethernet, the most
widely installed local area network technology in use today. PoE
allows the electrical power necessary for the operation of each
end-device, to be carried by data cables rather than by separate
power cords. It minimizes the number of wires that must be used
in order to install the network, resulting in lower cost, less
downtime, easier maintenance and greater installation
flexibility. PoE enables quality power for IP telephones (VoIP)
and many other low power Ethernet network devices like the
Wireless LAN access points and security cameras.
The main benefits of Power over Ethernet are:
- Quick, cost-effective installation that uses existing
data network cables without the need for additional power
sockets or wiring
- Easy, plug-and-play installation with no configuration required
- Centralized power management for improved energy
efficiency, reduced electrical costs and enhanced
troubleshooting capabilities
- Intelligent device detection that checks attached devices
to ensure that they can accommodate power signals
- Enhanced availability for continuous, high-quality data communications
- Cost-saving backup protects against overloads and shorted circuits
- Investment protection for legacy systems
IEEE 802.3af standard
The IEEE 802.3af standard has been approved on June 12, 2003, by
the Institute of Electrical and Electronic Engineers (IEEE).
The IEEE 802.3af standard defines the specifications to deliver
Power over standard Ethernet cables and in particular the
following issues:
- Legacy Installation - Power over Ethernet ensures safe
delivery of power to existing legacy devices as well as power-
enabled terminals.
- Preservation of Cabling Infrastructure - PoE avoids
altering existing wiring and does not damage cabling
infrastructure already in place.
- Data Integrity - Power delivery over Ethernet cables does
not cause data degradation or loss of data integrity.
IEEE802.3at DTE Power Enhancements Task Force
The IEEE has approved in September 2005 the creation of the
IEEE802.3at DTE Power Enhancements Task Force.
The 802.3at standard should extend the 802.3af power delivery
and port-level resiliency capabilities, what would largely
extend the number of applications that could benefit from Power
over Ethernet.
Power over Ethernet Midspan Range of Products
Microsemi's IEEE 802.3af standard compliant 6500 and 3000 Power
over Ethernet Midspan families, as well as the 6000G (Gigabit)
and 8000 (High Power) Midspans offer a highly cost-effective and
reliable means for upgrading the network to Power over Ethernet
without replacing existing Ethernet switches. Microsemi's PoE
Midspan products offer a number of advantages. A single Cat 5
cable provides both data and power eliminating the need for a
separate wire to power the end devices. Wireless LAN APs and
security cameras can be installed without the additional expense
of contracting an electrician to install AC outlets where
deployed. It further gives the option to install in places where
performance is optimum and not tethered to an existing AC
outlet. This is especially vital for devices like Wireless LAN
APs, which may be installed in hard to reach places like the
ceiling in order to achieve the broadest coverage.
Microsemi Acquired PowerDsine
Microsemi Corporation (Nasdaq:MSCC) has acquire PowerDsine Ltd.
With this acquisition, Microsemi, a world leader in the design
and manufacture of high performance analog solutions and high
reliability semiconductor solutions, expanded its portfolio of
product offerings to include a broad range of Power over
Ethernet ("PoE") solutions and further enhances its strong
analog and mixed signal design capabilities.
PowerDsine design, develop and supply integrated circuits,
modules and systems that enable the implementation of Power over
Ethernet in local area networks, providing the capability to
deliver and manage electrical power over data network cables.
PowerDsine offer integrated products and system solutions to
communications equipment manufacturers in the telecom and
datacom industries who incorporate them into, or bundle them
with, their products. PowerDsine is a founding, active and
contributing member of the IEEE 802.3af and 802.3at Task Forces
and the Ethernet Alliance.
