I agree with Mike.  Whenever I’m presented with another “do xxxxxx over wifi 
because it’s more convenient” I usually let them know I cannot guarantee that 
my wifi .. which is a requirement for and by the students .. will not interfere 
with their installation.  If they are ok with that, then go ahead.  I’d also be 
concerned about using a consumer-based home automation technology in an 
enterprise environment.  Was X10 not available ;)?

My personal opinion remains .. if it isn’t going to move, it shouldn’t be 
wireless.

All of that being said, maybe this is your opportunity to get more funding to 
move WiFi to 5GHz and leave 2.4 for IoT junk?

-Brian

From: The EDUCAUSE Wireless Issues Constituent Group Listserv 
[mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] On Behalf Of Mike Atkins
Sent: Thursday, March 23, 2017 11:35 AM
To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU
Subject: Re: [WIRELESS-LAN] Wireless Lighting Controls - impact on Wi-Fi or 
Wi-Fi's impact?

I would be concerned about your campus WiFi overrunning the ZigBee operation.  
We have a similar situation with ZigBee probes used to monitor freezer 
temperatures.  Campus WiFi is not heavily used in the kitchen areas so no 
issues to note for either side.



Mike Atkins
Network Engineer
Office of Information Technology
University of Notre Dame

From: The EDUCAUSE Wireless Issues Constituent Group Listserv 
[mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU<mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU>]
 On Behalf Of Williams, Jess
Sent: Thursday, March 23, 2017 10:07 AM
To: 
WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU<mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU>
Subject: [WIRELESS-LAN] Wireless Lighting Controls - impact on Wi-Fi or Wi-Fi's 
impact?

Our campus Facilities department is looking at a wireless lighting control 
system that uses a "Zigbee based" 2.4GHz wireless protocol.  An example use 
case for this system is a parking garage that has 86 lights which are connected 
using a mesh network, however I can see it spreading indoors at some point down 
the road.  At a minimum, I know this will raise the noise floor.  Does anyone 
have any experience with a similar situation/technology that can share how this 
impacts your campus Wi-Fi or how Wi-Fi has impacted the lighting control 
system, etc?

The product is AcuityControls XPoint Wireless lighting controls
http://www.acuitybrands.com/products/controls/xpoint-wireless#e8f40e39-86a8-4d2e-9072-e8b872bce11b


I'm told by the manufacturer that the default channel used is Zigbee Channel 
15, which is 2.425 MHz (5MHz total channel width).  The channel can be changed.

Vendor says:
"XPoint Wireless Mesh operate a low duty cycle, narrow band (5 MHz wide) 
communications at up to +18 dBm output power, whereas 2.4 GHz Wifi operates at 
a high duty cycle, wideband communications (typical 20 to 60 MHz wide) 
typically at up to +23 dBm (that’s log scale so that’s a 5 dB difference which 
is actually over 3x as powerful as our system). I’ve never once seen a 
confirmed case where our Zigbee based mesh network interfered with their Wifi." 
 They promise it won't interfere with Wi-Fi.

I'd be more comfortable with something that uses 900MHz instead of 2.4GHz.

Vendor documentation:
XPoint Wireless uses a low duty cycle, narrow‐band, Zigbee®‐based 2.4 GHz 
wireless protocol that is not
known to interfere with your 2.4 GHz WiFi or other systems. The low 
communication duty cycle,
combined with clear‐to‐send backoff capability from the IEEE802.15.4 radio, 
typically does not produce
measurable impact to WiFi performance and is usually difficult to observe in an 
RF spectrum analyzer.
Each XPoint Wireless Bridge and associated mesh network (typically up to 250 
wireless devices) can also
be programmed to use a specific Zigbee RF channel to avoid co‐channel 
interference with other installed 2.4 GHz equipment. Zigbee channels 11‐26, 
corresponding with 5 MHz‐wide frequency bands from
2.405 GHz to 2.480 GHz may be assigned to specific wireless mesh networks.

The wireless communication is secured and encrypted using AES 128‐bit 
encryption. The network
protocol includes “replay” protection, where each wireless message is uniquely 
encoded such that it
cannot be recorded and replayed at a later time.

Maximum RF power output is +18 dBm for Zigbee Channels 11‐25, 0 dBm for Channel 
26.
Output power is typically attenuated 2‐20 dB by LED luminaire housing.

Thanks,



Jess Williams

Sr. Network Engineer, Network Engineering
University of Tennessee at Chattanooga
Helping Students Achieve Excellence through Technology
jess-willi...@utc.edu<mailto:jess-willi...@utc.edu>
423-425-2372
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