| Term |
Definition |
| Bluetooth |
Low speed short distance wireless standard specified by the Bluetooth Special Interest Group |
| Bluetooth master |
A master initiates a connection. A master may have multiple connections. A master decides which slave to poll. |
| Bluetooth slave |
A bluetooth slave receives a connection. Master and slaves can reverse after connection. |
| Bluetooth central role |
BLE standard. Device that monitors a number of bluetooth peripherals. |
| Bluetooth peripheral role |
BLE standard. Through Bluetooth 4.0, a device with peripheral role has only one bluetooth connection. At Bluetooth level 4.1, peripherals may have multiple connections. Used for low-power applications where a small battery can keep a BLE peripheral role device running for years. |
| BLE |
Bluetooth Low Energy communication standard. Defined in Bluetooth 4.0 and above. Used by sensors to conserve power. |
| BT |
Bluetooth Classic |
| GATT |
Bluetooth Low energy Generic Attribute A hierarchical data structure for bluetooth devices. |
| GATT client |
This is the central device. |
| GATT server |
A program that defines the attribute structure for BLE devices. This is a peripheral device, typically a sensor. |
| GLONASS |
Russian global satellite positioning system |
| GNSS |
Global Navigation Satellite System (generic) |
| GPS |
Global Positioning System (US) |
| GPSD |
Server that monitors the GPS and makes time and position information available to client programs, such as gpsmon and NTPD. Allows multiple programs to use the GPS. Detects leap second and tells NTPD of an upcoming leap second and its direction on the day of the leap second. |
| NMEA |
A serial port and messaging standard for marine equipment including GPS. |
| NTPD |
Program that provides time as a service. Time is input to NTPD from a GPS, the local system clock, or an external NTP server. The system clock and hardware clock is adjusted to match the external time source. |
| PPS |
Pulse per second |
| UBX |
Ublox proprietary GPS message format |
| VAP |
Virtual Access Point, software device used to define a WAN (Wi-Fi) connection. |
| Wi-Fi |
The various IEEE 802.11 standards |
| Wi-Fi Station |
The mode where the device attaches to a router to provide access to a LAN or the internet. Typically the remote system provides a gateway, DNS, and DHCP. |
| Wi-Fi Access Point |
The mode where the device acts as a router, providing a gateway, a DNS, and typically DHCP. |