Ethernet switch makers Cisco and Nortel this week said network professionals should start paying a lot more attention to keeping their wiring closets cool and energy efficient as power consumption grows.
During an Interop panel discussion called "Making the (New) Switch," product planners and managers from these vendors shared the new directions their Ethernet switch designs are taking, as well as what IT shops should do to be ready for them.
One technology that enterprises are widely upgrading to in wiring closets is Power over Ethernet (PoE). Issues that arise from this technology include heat dissipation from the increased power draw of PoE gear, as well as management and allocation of power. The emergence of higher-powered PoE, or PoE Plus, is another issue LAN managers should keep an eye on in the future.
"PoE Plus will push a whole bunch of new electrical dynamics for supplying power," said Mark Leary, senior strategist, network systems at Cisco. "But there are a lot of considerations. We're already seeing wiring closets running rather hot when supporting a lot of 15-watt IP phones. Obviously 30 watts really would push that up."
Cabling could be another issue for PoE Plus. "It's the same situation as when we went to Gigabit over copper," Leary said, adding that many users thought existing Category 5 could support the higher speed reliably, but discovered it could not. "Users may find the same thing" with PoE Plus, he said.
The idea of powering new kinds of endpoints intrigued some in the audience. "Being able to power laptops or small desktops or thin clients would be a fantastic help," said one audience member, who did not want to be identified.
Sanjeev Gupta, Nortel's director of Ethernet switching, was more skeptical of the near-term demand for PoE Plus.
"I think it's a solution in search of a problem," he said. "There aren't enough end devices around that would require it."
One network equipment customer on the panel suggested maybe more DC power options should be available to enterprises, as new PoE standards emerge and VoIP and wireless LAN (WLAN) deployments demand more juice coming from overheated wiring closets.
"If you just had DC power supply directly into switches, that could be more efficient electrically," said David Peers, manager of network development and engineering at the University of Nevada, Las Vegas. He said this is already happening with servers as vendors look to make racks of data center boxes run cooler. "That should be more of an option in switches."
Nortel's Gupta said this strategy is used in large carrier networks, and could translate to enterprise data centers, but would be impractical for wiring closets.
"Today there are switches that use DC," he said. "Central office devices do this. Not many enterprises have the capacity to support that,however. This requires special air-flow and other requirements that just won't be in a wiring closet."
DC power to switches aside, Ethernet vendors said the emergence of the green issue in IT is forcing them to rethink how their gear is powered and the electricity managed.
"With PoE and the greening of IT, we're trying to find ways to make [switch] power supplies more intelligent," Cisco's Leary said. "If a switch has [certain PoE] requirements, you may not necessarily have to be burning a whole power supply all of the time. So you're going to see a lot of smart power management facilities over the coming years. It's a huge issue in the data center. And it's going to be an even bigger issue in the wiring closet if we do indeed start to hook up 300 to 400 end-user devices, drawing power out of the wiring closet. The wiring closet better be very cool."