Universal Power over Ethernet
Power over Ethernet (PoE) has made it very easy to deploy VoIP telephones, wireless access points, and many other network connected devices. The Institute of Electrical and Electronics Engineers (IEEE) ratified the PoE standard 802.3af in 2003 which allocated 15.4 watts of power to a device. The next standard was 802.3at and was ratified in 2009 providing 30 watts of power to a device. This allowed an ethernet switch to power more powerful devices.
As with anything in technology, the demand for PoE devices has grown over the years. As a direct result, a new PoE standard, 802.3bt, is in the process of being ratified by the IEEE that will deliver up to 60 to 100 watts of power to a device. Previous iterations of PoE utilized four out of the eight wires within an ethernet cable. 802.3bt utilizes all eight wires, hence the nickname 4PPoE (4 Pair Power over Ethernet). The IEEE estimates that the 802.3bt standard will be ratified in September 2018 (IEEE).
|802.3af “PoE”||802.3at “PoE+”||802.3bt Type 3 “4PPoE”||802.3bt Type 4|
|Year Ratified||June 12, 2003||January 31, 2009||Est. September 2018||Est. September 2018|
Note: Type 4 will require a new ethernet cable standard to be introduced
Cisco first introduced their interpretation of 802.3bt in 2011 (Cisco) and call it Universal Power over Ethernet (UPoE). UPoE is designed to handle the increased demand from multi-radio wireless access points, thin clients, pan/tilt/zoom cameras, digital signage, building automation systems, sensors, etc. Imagine powering a thin client and a telephone by just the ethernet cable itself. This reduces clutter and eases deployment. Imagine installing LED lights that are powered by UPoE. This would give facility managers greater control over the look, feel, and power usage of the lighting system. The future will bring us more products that will push towards greater consolidation, ease of deployment, and broadened expectations of what is possible.
Wireless demand has grown year over year ever since its inception. The newest wireless technologies push the wired backbone to extremes. Replacing current generation wireless access points with new models could lead to bottlenecks. Most installations run a single ethernet cable to the access point location. In the wiring closet, the access point connects at 1Gbps. Next generation access points are capable of exceeding 1Gbps of throughput, thus placing a bottleneck on the connection between the wiring closet and the access point. Such access points usually have two 1Gbps ethernet ports on them to help prevent any slowdowns. What if you only pulled a single ethernet cable to older access points and you want to swap them out for newer models? One option would be to pull an additional cable to every access point in the building, leading to increased material and labor cost. In a massive building with difficult to access cable runs, this could be very costly.Another option is to purchase a multi-gigabit switch which could help to avoid material and labor costs while limiting or eliminating the bottleneck between the switch and access point. A multi-gigabit switch, such as the Cisco C9300-24UX has the capability of connecting to devices at 100Mbps, 1, 2.5, 5, or 10Gbps. The IEEE standard name given to multi-gigabit is 802.3bz-2016. The main driving force for creating this standard is the new generation of wireless access points that can exceed 1Gbps of throughput and greater capabilities with Cat5e cables. Utilizing a multi-gigabit switch, a Cisco 3800 access point can connect up to 5Gbps on a single ethernet cable (Cat6 or higher).
Combining the Two
The combination of Universal PoE and Multigigabit Ethernet help to futureproof a network for whatever may come. However, these technologies might not fit every installation. A great understanding of the current network along with a well thought out timeline will make the decision easier.
Cisco. 7 July 2011. <https://blogs.cisco.com>.
Cisco Aironet Series 2800/3800 Access Point Deployment Guide. 25 January 2018. 13 March 2018. <https://www.cisco.com>.
IEEE. 9 November 2017. <http://www.ieee802.org>.