Hello folks.
My client is unsatisfied with my response to his query below.
Can you please either
1.confirm that my response is professionally satisfactory, or
2. please tell me if I am mistaken, or what would be good to add to my response?
Thank you.
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CLIENT: You stated, “This error message was discovered during the investigation and I would like to know what it means and what generates this error.”
"Apr 8 11:22:49 NCI: E1: Sensor receive failure (-1), 104
Apr 8 11:22:49 NCI: E1: Fatal condition, shutdownNci needed, Receive Failure
Apr 8 11:22:49 NCI: CLEANAIR: Slot 1 error detected"
MY RESPONSE: A sensor receive failure is caused when the wireless access point is unable to decipher the electromagnetic information in the signal from the client device.
After much research, it is clear that this error is almost always caused by typical environmental obstacles of wireless technology.
Despite abundant users experiencing this issue, the internet revealed zero instances of direct solutions to this issue; thus, deduction concludes that the only solution is to follow best wireless deployment practices such as:
- configuring nearby APs to use different frequencies and channels, adjusting antenna gain, and raising the minimum noise floor,
- eliminating electromagnetic interference such as close proximity to microwaves and other wireless appliances and clients,
- eliminating physical interference such as pine trees, metallic structures, and utilization during precipitation.
I've included below, relevant links and snippets for your knowledge base. Because this sensor receive failure is such a common problem, there has been at least one professional conference (listed below) to solve the issue as technology advances.
Speaking generally—The most important factor regarding wireless network stability is to confirm that an initial site survey was performed correctly. This is vital, because not only can a poor site survey result in coverage holes which cause radio resource management (RRM) instability, but also too much coverage, as well as too strong radio power will also cause RRM instability in which clients disconnect because of aggressive roaming triggers. The AP’s and controllers in the wireless deployment behave as a single self-correcting organism—one change often affects all other devices.
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Cisco bug search...
-Cisco 3800 AP FW stopped working on Radio 0
-COS AP sensor failing
-AP 3802 CleanAir Resets with error: CLEANAIR: Slot 0 error detected
-Frequent Cleanair down events at AP3800
-Cleanair Slot 1 down events in 3800 AP
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21st European Symposium on Computer Aided Process Engineering
https://www.sciencedirect.com/topics/computer-science/sensor-failure
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https://help.brinkshome.com/hc/en-us/articles/224877388-I-am-getting-a-sensor-failure-What-is-causing-that-How-can-I-fix-it-
"The wireless sensors are powered by small batteries, which leaves open the possibility that an unusual power drain can deplete the batteries and cause a sensor failure."
"Check for wireless environmental interference:
Wireless internet routers near the panel can cause interference.
Wireless internet routers near the sensors can cause interference.
Plaster walls with metal wire can cause interference.
AC lines running directly behind the panel can cause interference.
Some cordless phones can cause interference, try powering down and test again.
Check for a wireless doorbell near the panel."
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https://www.accentsjournals.org/PaperDirectory/Journal/IJACR/2013/9/23.pdf
"The most formidable gainsays of physical layers are fixed bandwidth, limited transmission range and poor packet delivery due to interference, attenuation, etc. According to [1], transmitter faults, receiver faults, the upper layer faults and noise are primarily considered as the sorted out fault occurrence at physical layer. The performance of both transmitter and receiver are commonly quantified by error vector magnitude. Here, performance degradation/ encounter of malfunctions at transmitter or receiver lead to transmitter or receiver faults respectively. Sensors in WSN are densely deployed, hence signal interferences is inevitable among the sensors. Unwanted variations in signal such as noise could also lead to a fault. The major causes of this noise are cross-talk, impulse noise, thermal noise. Such faults degrade the signal to noise ratio. Thus interference, multicasting and synchronization are most notable categories of physical layer design management. Interface error between host and network interface unit are referred to as upper layer faults. Common interface error that occurs in the network is intermittent. To obtain reliable WSN-physical layer, efficient error control strategies to be implemented according to the parametric schema of specified International Journal of Advanced Computer Research (ISSN (print): 2249-7277 ISSN (online): 2277-7970)
Volume-3 Number-3 Issue-12 September-2013 157 wireless medium. In order to ensure a FT in WSN system, several aspect of physical layer designing has to be considered, since it has potential to block the failure of node that may happen due to planned failures such as energy depletion."
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