The ABCs and 123s of PoE
By Thomas Lewis, Texas Instruments
Power over Ethernet (PoE) is a long-established, well-adopted power delivery technology that injects power over 100 meters of standard Ethernet cable defined in IEEE 802.3TM standards. It radically simplifies installation for traditional end equipment such as IP phones, wireless access points, and IP cameras. With the power source increased up to 90W, new PoE end equipment like intrusion control panels, advanced occupancy detection, industrial lighting, medical devices, professional AV equipment, and digital signage are taking advantage of standardized PoE benefits.
As PoE installations proliferate, so have the range of PoE capable devices using different brand names and terminology with no visible way to distinguish between standardized and non-standardized solutions. Interoperability issues and market confusion have resulted. The Ethernet Alliance, a global consortium dedicated to market education and advancement of Ethernet technologies, has introduced the Ethernet Alliance (EA) PoE Certification Program to distinguish PoE standards-compliant products from non-standard PoE implementations. Its goal is to improve end-user experience by vastly improving interoperability and eliminating market confusion.
With all of this excitement, also come interoperability complexities and challenges that strike to the core of what made PoE so popular to this point. The new Gen 2 EA PoE Certification Program rises to meet these challenges and extends multiple benefits across the entire PoE business ecosystem, including component manufacturers, system vendors and ultimately consumers. Table 1 summarizes the benefits.
|EA PoE Certification Program benefits||PoE system stakeholder benefiting|
|Integrated circuit vendors||End-equipment manufacturers||System installers||End users|
|Ease of installation||X||X|
|Enhanced designer support||X||X||X||X|
|Improved designer perception of PoE||X||X||X|
|Reduced evaluation costs, faster time to market||X||X|
|Avoiding unnecessary development/lost opportunity costs||X||X|
Table 1: PoE Certification logo benefits and beneficiaries
The new IEEE 802.3bt™ standard and Gen 2 EA PoE Certification progam utilizing distinct logos will enable vastly improved interoperability and cannibalize multiple non-standard solutions that jumped in and temporarily filled the technology void while the new standard worked its way through IEEE 802.3 committee work. Those competing interim solutions were quite the assortment of alphabet soup and muddied the industry’s ability to speak clearly.
The need for simplified terminology to aid industry communication is also clear. Moving forward, the Ethernet Alliance will refer to PoE technology and certification options according to the brands and associated programs shown in Table 2. Simplifying the language utilized across the industry will greatly ease confusion and aid efforts to explain what’s needed.
|Brand||Standard||Clause Title||Ethernet Alliance
|PoE 1||IEEE 802.3af||Clause 33:
Power over Ethernet over 2 Pairs
|PoE 2||IEEE 802.3bt||Clause 145:
Power over Ethernet
|SPoE 1||IEEE 802.3cg||Clause 104:
Power over Data Lines of Single Pair Ethernet
Table 2: PoE brands, associated standards, and EA PoE Certification
You will note inclusion of “SPoE 1” and its association with the IEEE 802.3cg specification. This is, of course, a brand new IEEE 802.3™ specification for Single Pair Ethernet (SPE). Like other copper Ethernet solutions, SPE delivers power and data with a single connection. We expect a transformative effect in Operational Technology (OT) networks, building and industrial automation, because of this capability.
The Ethernet Alliance chose this new language for three reasons:
- It makes the connection between IEEE 802.3™ products and Ethernet Alliance testing suites exceptionally clear.
- It follows other industry-standard nomenclature such as USB x and Wi-Fi x, where the “x” indicates a specific generation of those technology types.
- It provides extensibility for branding additional PoE technologies defined by IEEE 802.3 standards.
When you see the brand labels “PoE 1” and “PoE 2”, and the Ethernet Alliance logo, it will clearly delineate IEEE 802.3 PoE solutions, the generation of IEEE 802.3 PoE solution, and whether the solution has undergone Ethernet Alliance testing.
For more information about the Ethernet Alliance PoE Certification program, please visit https://ethernetalliance.org/poecert/
Bio: Thomas Lewis is an Ethernet Alliance member and Marketing & Applications Manager for Power over Ethernet (PoE) Solutions at Texas Instruments. In this, role he is responsible for all elements of the marketing strategy and applications support for its PoE product portfolio.