From the horse’s mouth
I have often heard the line that the Power-Over-Ethernet technology, which supplies power to a network device connected via twisted-pair Ethernet cable using that same cable, and HomePlug powerline-networking technology are mutually exclusive technologies.
What is Power-Over-Ethernet and what is it used for?
The common 802.3af and 802.3at Power-Over-Ethernet technologies make use of the Category-5 “twisted-pair” Ethernet cabling that is used to transfer data to the network also as a power-supply cable. The main advantages are that you don’t have to have an AC outlet close to a network device and you can just run one cable to that device to allow it to function.
The typical implementation is either an Ethernet switch that has Power-Over-Ethernet ports providing power to a VoIP desk telephone, wireless access point or IP-based video-surveillance camera. This appeals to businesses as a way of providing centrally-managed power for these devices as well as allowing for simplified cost-effective installation and reliable operation.
What is HomePlug AV powerline network technology
The HomePlug AV network technology uses the building’s existing AC wiring as a data conduit. This provides a “no-new-wires” wired network setup for homes and other installations where it is not cost-effective to have Ethernet wiring in place and has shown a strong appeal for temporary wired-network setups.
Even if a building has Ethernet wiring in place, the HomePlug AV technology works as a way of extending this network in a temporary or semi-permanent manner. In some cases, the HomePlug technology can work as a cost-effective wired network link between a house and an outbuilding such as a detached garage if there is AC wiring in that building which isn’t separately metered.
Of course most of these network segments have network client devices connected via a short Category-5 Ethernet cable to a HomePlug-AV-Ethernet bridge adaptor typically referred to in the UK as a “homeplug” in the case of the common single-port wall-wart device.
Why am I impressed with the Asoka PL-9660POE “homeplug”
This adaptor is both a single-port HomePlug-AV-to-Ethernet network bridge along with a Power-Over-Ethernet power supply according to the 802.3af standard. Here, I could connect a Wi-Fi access point or VoIP desk telephone that can be powered using Power-Over-Ethernet to this device and it provides power to that access point while linking it to the HomePlug AV powerline-network backbone.
The advantages seen here is that I only use one AC outlet to link the network device to the HomePlug segment as well as providing power to it rather than having to have another AC outlet or double-adaptor being used for another wall-wart. You also benefit from only needing one cord between the device and this HomePlug adaptor which is easier to manage in to an aesthetically-pleasing setup. This is of importance when you are using an wireless access point to extend your wireless network and you would find that having that access point up high with a clear line of sight to the laptops, tablets and smartphones used in that area would yield optimum network performance and battery runtime for the mobile devices. It is compared to using a HomePlug wireless access point which will typically be installed at floor level and obscured by furniture and may not be able to perform adequately.
What about transportability when you are thinking of that VoIP desk telephone? Typically, a furniture and equipment arrangement may suit one’s current needs but these needs do change. This adaptor may allow you to reposition the phone to a newer location as you see fit even in a semi-permanent manner such as if you are moving the cash-wrap stand in your shop to a newer location to cater for a sale or you simply wanted to bring the VoIP conference phone out only when needed.
This device may also help with legitimising the Power-Over-Ethernet technology for the home network. Examples of this could include “two-piece” HomePlug access-point kits; small consumer-AV applications like tabletop Internet radios, network speakers or digital picture frames; or even all-in-one computers that can be powered through the Ethernet conneciton. To the same extent, computers like tablets, small notebooks and “adaptive all-in-one” computers of the same ilk as the Sony VAIO Tap 20 can benefit from using their Ethernet port as a power connection option to charge up their batteries or allowing the user to avoid compromising battery runtime,
Even an Internet-gateway router could be powered using this method as an alternative to the separate power brick that these devices come with. As well, using a Power-Over-Ethernet power splitter which provides 12 volts or 5 volts DC to a device that isn’t capable of Power-Over-Ethernet from an 802.3af Power-Over-Ethernet connection could yield benefits to the home network by eliminating the need to use a “wall-wart” or “power-brick” and a separate AC outlet to power network devices.
Points of improvement with this device
Here, the HomePlug standard that this device supports could be the HomePlug AV 500 / IEEE 1901 standard for better data throughput. This is more so as this standard becomes the norm for most HomePlug AV segments. As well, a variant that supports the 802.3at Power-Over-Ethernet Plus standard could be made available and pitched towards set-top-box applications. But these improvements may require further power-supply engineering to cater for higher power loads.
Similarly, the Asoka “homeplug” could be made available under an OEM-contract to other vendors to sell to customers so as to make the concept more ubiquitous. For example, having this fitted with the Continental-standard AC plug and sold in to France could work hand-in-glove with the “décodeurs” (TV set-top boxes) that are part of the many “n-box” triple-play Internet services offered in that country. Here, these would work as a convincing easy-to-implement alternative to a “homeplug / power-supply” box like the Freeplug that is used to link the “n-box” Internet gateway device and the “décodeur” set-top box. These boxes typically have three wires with one to the power outlet and two to the “n-box” or “décodeur” device.
I just hope that this device isn’t just a “flash in the pan” when it comes to HomePlug and Power-Over-Ethernet but a way to prove to the industry that these technologies complement each other.