Network professionals should start paying a lot more attention to keeping their wiring closets cool and energy efficient as power consumption grows, according to Ethernet switch makers Cisco and Nortel.

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 15W IP phones. Obviously 30W 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 Cat-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 centre 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 centre. 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."

Ethernet switches going soft

Another big trend for new and future switches is the expanding role of software in the devices, panelists said.

This goes far beyond GUI-based configuration tools and network monitoring applications. Software making its way into edge and core switches provides services such as security with network access control, intelligent endpoint device discovery, WLAN/LAN integration, and acceleration and routing of higher-level messaging protocols

"It used to be that software in networking was something that you used to configure a switch. Then you wanted software to get the hell out of the way, Cisco's Leary said. "That's no longer the case. Now it's software and hardware working in concert. There's a lot of flexibility in terms of service deployment. The hardware now accelerates software and provided advanced services. That notion of years ago, that if it's not in software it's slow... that's not what's going on now."

Of course, just because newfangled switches are on the way doesn't mean IT shops will rush out to buy them. A quick show-of-hands poll of the audience members -- prompted by Dell'Oro analyst and panel moderator, Seamus Crehan -- demonstrated that most among the 100 or so attendees were keeping wiring closet LAN switches around for about four years.

"People will re-deploy and reuse products that have worked well for them in the past," Nortel's Gupta said. "We have seen product life cycles go sometimes for eight to 10 years."