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Power over Ethernet nice now, better soon
Modern digital technology is catching up with the telephone system from the 1950s. How? Ma Bell used to send voltage down the phone wires to ring the bell on your phone. Today, PoE (Power over Ethernet) sends voltage down the network wires to power a variety of digital devices. That's helpful, but a coming upgrade may really make some powerful, or rather less power-hungry, news.
Officially, the standard for Power over Ethernet is IEEE 802.3af. Practically, PoE switches (called PSE for Power Sourcing Equipment) can deliver just under 13 watts to devices (called PD or Powered Device). Since most desktop computers have power supplies delivering 300 watts or more, you might think PoE can't do much. For computers, you're right, but let's look at what's at the end of many powered Ethernet cables.
The two most popular PoE devices are Voice over IP telephone handsets and wireless access points. While phones tend to be on desks close to power plugs, running the power and voice/data signals over the Ethernet line does reduce the number of cables spawning under your desk. This is a bit handy but not a huge deal maker.
Continued
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