By Sreeram Krishnamachari, Global Product Line Manager, HP Networking
Recently, I’ve witnessed some great networking technologies reach the market: 10G on copper, FCoE, switch virtualization, unified management—the list goes on. All these technologies aim to solve one problem or another for network administrators.
But once in a while, I come across a solution that’s looking for a problem. Case in point: Cisco’s recently announced UPoE, or Universal Power over Ethernet. A proprietary version of PoE (Power over Ethernet) technology, UPoE is a new module for the Catalyst 4500, which delivers up to 60W/port at the switch. And this module will work only with the (super) expensive SUP 7.
A Power over Ethernet (PoE) primer
To clarify, PoE enables power delivery through CAT cables for network connectivity. When PoE was introduced about 8 years ago, it delivered up to 15.4W per port. It was used primarily for powering up access points located in ceilings, where it is difficult to build out a power outlet.
Over time, as the price for PoE declined, other applications like VoIP phones and cameras began adopting the technology. Approximately four years ago PoE+ was introduced. It increased power consumption to 30W/port and provided more granular power delivery. Interestingly, since the introduction of PoE+, very few applications have taken advantage of its extended power.
I recently browsed more than a dozen powered device (PD) vendor websites for IP cameras, VOIP phones & PoE access points, and took note of the peak power consumption. Out of 104 devices I looked at, only three consumed more than class 3 PoE power. And these devices used only 16 to 18W of peak power. And this is the situation for a standards-based technology (IEEE 802.3at). For the statisticians in you, check out the normal distribution of the peak-power consumption of these devices in the adjacent image:
Is UPoE’s really worth it?
Now, a networking vendor introduces a 60W per port proprietary technology without the backing of ANY standards.
And the proposed use for the technology is to power other switches. The question I can’t help asking myself is why? UPoE sounds like a solution looking for a problem.
- In general, PoE is not an efficient technology for transmitting large amounts of power. Approximately 18% of power is dissipated through the cable. In other words, for every $1M of electricity I buy, I lose $180K to dissipation!
- Switches, unlike phones or access points (APs), are in fewer, more specific locations within a campus – it is much easier, greener and economical to provision a power outlet in a closet vs running long UPoE cables.
- Even assuming a plethora of applications to take advantage of this higher power range will emerge, there is no guarantee that these future devices will run on Cisco’s UPoE implementation as it is not standards based.
Read about PoE’s implementation issues yourself
For the record, when Cisco introduced its proprietary version of PoE several years ago, it created all sorts of problems in connecting standards-based PoE devices to its switches. It was due primarily to implementation differences between what was defined and approved by the IEEE standards body and Cisco’s proprietary implementation.
You can read about the issues in Cisco’s support forum.
So to summarize, there are few to no applications for UPoE. It is proprietary, costs a fortune and isn’t very sustainable!
Is UPoE really solving a problem? Or is it a solution just looking for a problem?
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