I've seen some interesting and informative posts regarding POE here. Thanks to those who've contributed. I thought some folks here might be interested to know that POE, when it was introduced in commercial LAN applications a half-dozen years ago, had already been used in numerous similarly configured wiring arrangements by telcos over the ages for powering remote devices and for loopback and other diagnostic purposes. In fact, subsequent to (or at about the same time) that the technique being sanctioned for Ethernet use, ANSI ratified a similar standard for powering field equipment in residential access networks and other outside plant carrier/telco applications, as well.
When it became an option for Ethernet in commercial wiring environments it effectively put a kibosh on many fiber to the x plans, and to a limited extent some wireless plans, as well, by changing the nature of the argument used to remove the 100 meter limitations prescribed for desktop and LAN switching elements. It effectively guaranteed the perpetuation of product sales, professional services and labor for the copper carter that included, but was not limited to: copper cable companies; architects, electrical and structural engineers, consultants and facilities planners; certain union classifications (signal grade electricians) within enterprises who design, engineer and install not only cabling systems but the equipment closets used for 100-ft proximate switches, HVAC and UPS systems in closets needed to meet distance constraints. Sometimes those closets could number four to six per floor, depending on the size of a floor plate. In a forty-story building this easily results in 38 * 4 or 152 fully conditioned equipment rooms and two data centers (primary and backup) for the building. The alternative approach, using fiber, would have extended a fiber to every end point via passive optical cross-connects on each floor - requiring no conditioning and saving about 30,000 sq ft of commercial real estate - homing to two or three data centers via diverse paths, or using alternate riser systems. The Majority Won. Frank --- DTI Consulting Inc. 212-587-8150 Office 347-526-6788 Mobile -- NYCwireless - http://www.nycwireless.net/ Un/Subscribe: http://lists.nycwireless.net/mailman/listinfo/nycwireless/ Archives: http://lists.nycwireless.net/pipermail/nycwireless/
