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ADTRAN's Port Scheduler GREENS the NetworkADTRAN's Port Scheduler GREENS the Network

For every phone or other PoE device that you power down, you save energy; weekends and holidays mean more savings

Matt Brunk

June 8, 2009

3 Min Read
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For every phone or other PoE device that you power down, you save energy; weekends and holidays mean more savings

Before purchasing our new ADTRAN 1335 router, I asked ADTRAN pre-sales whether or not I would get the feature for automatically turning on/off PoE ports. Forgetting about this project, I was recently reading about ADTRAN's new 1534/1544 switches with the new feature -Port Scheduler--that is used for this capability. It was one of those rare moments that I didn't mess around with our new router settings under "Port Scheduler" until I read the new switch brochure. ADTRAN uses a wizard to setup Port Scheduler and it takes 10 minutes--9 to think about it and then one to implement.For those using DHCP for their IP/SIP phones you may want to think this one out a little further because you don't want to jam the server with DHCP requests all at the same time, and you also need to allow time for the phones/devices to boot. If opening hours are 8:00 am then you don't want phones to begin to power ON at 8:00 am because callers and users may end up disappointed. Another consideration is to ensure that dial tone isn't turned off where you may need it 24x7 for emergency or operational situations. The more phones you have, of course, the more input/feedback you will need to gather in order to implement Port Scheduler. Port Scheduler offers other options and be sure to get Network Time Protocol (NTP) working and on the right time zone.

Benefits of using Port Scheduler:

* For every phone or other PoE device that you power down, you save energy; weekends and holidays mean more savings

* Less power consumption means lower energy bills but it also means reduced heat in the closets

The (potential) disadvantage of using Port Scheduler:

* We've been pushing 24x7 access to dial tone and with phones booting up once a day, will something go wrong? Then on the flip side of this, if the system responsible for giving out IP addresses fails, does it matter?

* IF you are running one phone/computer through one cable then you need to consider how to implement software updates to the computer

* Not knowing the personnel that return to the office during off-hours and weekends to work may disrupt their work without a desk phone or access point

Our access points use about 7 WATTS of power while all of our IP/SIP phones are around 3 WATTS. Just one IP/SIP phone that is turned down from 6:00 pm-6:00 am provides a daily savings of 36 WATTS. Then, if that phone isn't needed during weekends that's 72 WATTS for either day during the weekend. Over one year (261 weekdays {*36WATTS} + 114 weekend days {*72 WATTS}) that's 17,604 WATTS for just one phone. Translate this to the utility then 17,604 WATTS equals 17.604 kWh (Kilowatt Hours) and the cost is about .12 per kWh or $2.11 per phone per year. Assume the same times for each access point and the savings is 41,076 WATTS or 41.076 kWh per year or $4.93 annual savings for one antenna.For every phone or other PoE device that you power down, you save energy; weekends and holidays mean more savings

About the Author

Matt Brunk

Matt Brunk has worked in past roles as director of IT for a multisite health care firm; president of Telecomworx, an interconnect company serving small- and medium-sized enterprises; telecommunications consultant; chief network engineer for a railroad; and as an analyst for an insurance company after having served in the U.S. Navy as a radioman. He holds a copyright on a traffic engineering theory and formula, has a current trademark in a consumer product, writes for NoJitter.com, has presented at VoiceCon (now Enterprise Connect) and has written for McGraw-Hill/DataPro. He also holds numerous industry certifications. Matt has manufactured and marketed custom products for telephony products. He also founded the NBX Group, an online community for 3Com NBX products. Matt continues to test and evaluate products and services in our industry from his home base in south Florida.