Resource usage

Network Resources

Data rate

The MuonPi detector board will send measurement data to our data evaluation servers, the rate of which greatly depends on the exact event rate. In a proper setup these messages will average out to roughly 600 messages per minute with an average size of 110 bytes. This however includes the acknowledgement packets which account for two thirds of the number of packets but they are only small in size (>150 bytes).

Purple: All messages send between the MuonPi unit and muonpi.org
Green: Only MQTT publish messages, excluding acknowledgement messages

Histogram of packet sizes over 45minutes

Used Ports

Port	Application
51508	GUI connection
8888	pigpiod
1883 (out)	MQTT message publish

MQTT Packet

Detector telemetry and mesurement data is send to our servers via the MQTT protocol. Upon receiving a MQTT message from the client our servers respond with an MQTT acknowledgment packet which is in turn acknowledged by the client with a short TCP message.

Generally two types of MQTT messages are send, the event message and the log message.

The event messages consist of the following:

Type	Size
Ethernet frame	14 byte
IP4 Header	20 byte
TCP Header	32 byte
MQTT message	84 byte
Total	150 byte

The log messages consist of multiple MQTT messages packed into a single (sometimes two seperate) TCP packets

Example data of multiple MQTT packets being send to our data evaluation servers:

#	MQTT topic	timestamp (rising edge)	timestamp (falling edge)	-	Event counter	-	-	-
1	muonpi/data/user/0	1611698307.895514697	1611698307.895515885	70	35109	1	2	1
2	muonpi/data/user/0	1611698307.912153060	1611698307.912154247	70	35110	1	2	1
3	muonpi/data/user/0	1611698308.237550951	1611698308.237552160	70	35111	1	2	1
4	muonpi/data/user/0	1611698308.404480192	1611698308.404481380	70	35112	1	2	1
5	muonpi/data/user/0	1611698308.699026112	1611698308.699027299	70	35113	1	2	1
6	muonpi/data/user/0	1611698309.048519516	1611698309.048520724	70	35114	1	2	1
7	muonpi/data/user/0	1611698309.133318449	1611698309.133319657	70	35115	1	2	1

Log message

The log message contains various meta data about your MuonPi setup.

Example log message:

MQTT topic	Date and Time	Variable	Value	Unit	Description
muonpi/log/user/0	2021-01-26_22-08-43	RXBufUsage	0.0000000	%	Buffer usage incoming messages
muonpi/log/user/0	2021-01-26_22-08-43	TXBufUsage	0.0000000	%	Buffer usage outgoing messages
muonpi/log/user/0	2021-01-26_22-08-43	adcSamplingTime	2.4608333	ms
muonpi/log/user/0	2021-01-26_22-08-43	antennaPower	1.0000000
muonpi/log/user/0	2021-01-26_22-08-43	antennaStatus	2
muonpi/log/user/0	2021-01-26_22-08-43	clockBias	-319713.3333333	ns	Offset of GNSS clock
muonpi/log/user/0	2021-01-26_22-08-43	clockDrift	-440.3333333	ns/s	Drift of GNSS clock
muonpi/log/user/0	2021-01-26_22-08-43	fixStatus	3		GNSS fix status
muonpi/log/user/0	2021-01-26_22-08-43	fixStatusString	3D-Fix	ms	GNSS fix status
muonpi/log/user/0	2021-01-26_22-08-43	freqAccuracy	265.0000000	ps/s
muonpi/log/user/0	2021-01-26_22-08-43	geoHash	u0ypy122vb		GeoHash
muonpi/log/user/0	2021-01-26_22-08-43	geoHeightMSL	177.8400000	m	Height above mean sea level
muonpi/log/user/0	2021-01-26_22-08-43	geoHorAccuracy	1.2220000	m	Horizontal GNSS accuracy
muonpi/log/user/0	2021-01-26_22-08-43	geoLatitude	50.5000000	deg	Location latitude
muonpi/log/user/0	2021-01-26_22-08-43	geoLongitude	8.7000000	deg	Location longitude
muonpi/log/user/0	2021-01-26_22-08-43	geoVertAccuracy	0.8540000	m	Vertical GPS accuracy
muonpi/log/user/0	2021-01-26_22-08-43	ibias	10.2492675	uA	Bias current for SiPMs
muonpi/log/user/0	2021-01-26_22-08-43	jammingLevel	9.0000000	%	Jamming level of GPS antenna
muonpi/log/user/0	2021-01-26_22-08-43	maxCNR	43.0000000	dB	Carrier to noise ratio
muonpi/log/user/0	2021-01-26_22-08-43	maxRXBufUsage	25	%	maximum buffer usage for incoming messages
muonpi/log/user/0	2021-01-26_22-08-43	maxTXBufUsage	4	%	maximum buffer usage for outgoing messages
muonpi/log/user/0	2021-01-26_22-08-43	meanGeoHeightMSL	185.35	m	mean height above sea level
muonpi/log/user/0	2021-01-26_22-08-43	positionDOP	1.7333333		position dilution of precision
muonpi/log/user/0	2021-01-26_22-08-43	preampAGC	1482.0000000
muonpi/log/user/0	2021-01-26_22-08-43	preampNoise	-87.0000000	dBHz	noise level of SiPM preamp
muonpi/log/user/0	2021-01-26_22-08-43	rateAND	0.0000000	Hz	event rate (AND)
muonpi/log/user/0	2021-01-26_22-08-43	rateXOR	3.0525173	Hz	event rate (XOR)
muonpi/log/user/0	2021-01-26_22-08-43	sats	20.7777778		number of GNSS satellites
muonpi/log/user/0	2021-01-26_22-08-43	systemFreeMem	815.3660000	Mb	free memory space in host system
muonpi/log/user/0	2021-01-26_22-08-43	systemFreeSwap	104.8540000	Mb	free swap space in host system
muonpi/log/user/0	2021-01-26_22-08-43	systemLoadAvg	0.2758790		average CPU load
muonpi/log/user/0	2021-01-26_22-08-43	systemUptime	2.6875	h	uptime
muonpi/log/user/0	2021-01-26_22-08-43	temperature	41.5104167	degC	Temperature (on PCB)
muonpi/log/user/0	2021-01-26_22-08-43	timeAccuracy	31.5000000	ns	event timing accuracy
muonpi/log/user/0	2021-01-26_22-08-43	timeDOP	0.9233333		timing dilution of precision
muonpi/log/user/0	2021-01-26_22-08-43	ubloxUptime	9771	s	UBlox uptime in seconds
muonpi/log/user/0	2021-01-26_22-08-43	usedSats	11.6666667		number of satellites in use
muonpi/log/v/0	2021-01-26_22-08-43	vbias	31.6119833	V	SiPM bias voltage
muonpi/log/user/0	2021-01-26_22-08-43	vsense	0.2405174	V	Voltage accross sensing resistor

The only privacy sensitive information contained in these messages are the geolocation and ambient temperature. (ellaborate in Privacy)