Glossary

Common terms used in this manual.

A

Alias: Short numeric identifier for Sparkplug metrics

B

BCD: Binary-Coded Decimal encoding

Burst Polling: Temporary high-frequency polling

C

Coil (CS): Modbus read/write bit

D

DDATA: Sparkplug device data message

DBIRTH: Sparkplug device birth message

DCMD: Sparkplug device command message

E

Edge Node: Gateway instance in Sparkplug terminology

H

Holding Register (HR): Modbus read/write register

I

Input Register (IR): Modbus read-only register

Input Status (IS): Modbus read-only bit

M

Modbus: Industrial communication protocol

MQTT: Message transport protocol

N

NBIRTH: Sparkplug node birth message

NDEATH: Sparkplug node death message

P

PDU: Protocol Data Unit (Modbus addressing)

Poll Rate: Frequency of tag reading

R

RBE: Report by Exception

S

Slave ID: Modbus device identifier

Sparkplug: MQTT-based industrial IoT protocol

SSO: Single Sign-On

T

Tag: Individual data point from device

Tag Group: Collection of tags with same poll rate

TLS: Transport Layer Security

U

Unit ID: Same as Slave ID