Why is 802.3at important? Remember, about a year ago, Michael Finneran wrote in The End of Ethernet? Wrong Question that, "along the way the role of the wired and wireless LANs will work themselves out." Companies are not going to rush to replace their "legacy" Cat5/5E wiring infrastructures, and to best utilize the existing wiring, it's possible to use one drop for one faceplate and get 4 GIG switched ports, with the first two providing PoE to the desktop--but only if you have a switch or mid-span solution that provides 802.3at PoE that forwards on ports 1 and 2 to take advantage of 3Com's 3CNJ2000, formerly known as "network jacks" now labeled "IntelliJacks." Still, 25.5 Watts per PoE port will juice more than IntelliJacks.The 3Com IntelliJacks save on labor, time, costs, and use existing infrastructure. The hook may be in performance if your Cat5/5E drops are too long, but the 3Com jack has potential to double up PoE gig ports meaning: use one PoE GIG port on a switch and get two GIG PoE and two GIG non-PoE ports delivered via the IntelliJack to the desktop, cubicles or work area, and this helps to reduce the physical number of cable drops. The street price is right around $150 and no installer required, meaning this is a labor saving device.
Last fall, I followed up with Shorten The Cable Drops! stating why cable drops need to shorten in length after mentioning it in SIP Means Change. Other arguments are that the closets don't or won't support more juice (power), real time communications is mostly lip service and Category 6A means an interim step or quantum leap depending upon how you look at it, and then LAN switches must support 802.3at to take advantage of that 25.5 Watts when using 3Com's solution. 3Com's IntelliJacks make sense because if you use the LAN switch capable of supporting 802.3at then you could reduce the closet footprint in some cases. Do the math and you may find that maybe 612+ Watts per switch is too much of a stretch to begin with. The IntelliJacks don't make the facilities problem go away but the IntelliJacks do make better use of available facilities. For new work, doing more with less wiring makes sense with the IntelliJack.
In the SMB/E and campus environments, we can do a lot with very little infrastructure combining these solutions. I think the larger enterprise is seeking "uniformity." Whether or not uniformity is maintained within the cable plant remains to be seen. Not all remain pure (this is meant to challenge you) and even for the ones that do remain healthy and managed, real time communications eludes you unless you redefine "real time." The time is closing in on the managed infrastructure and cabling practices of old. One cable to the desktop is no longer a "soft benefit" of adopting IPT but what you are now seeing is a "requirement" and no longer a benefit.
