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iBeacon packets

  • Updated

iBeacon advertising packets are the messages that your beacons transmit continuously announcing their presence to nearby devices. When you receive your beacons, they will already be transmitting iBeacon advertising packets. Kontakt.io beacons start to send advertising packets as soon as their battery is installed.

  • Advertising packets are compatible with Apple iBeacon™ standard.

  • Advertising packets for the default Kontakt.io Beacon preset are transmitted every 350ms.

  • iBeacon packets are broadcasted as a connectable undirected advertising (ADV_IND).

    Only the Beacon Pro model broadcasts iBeacon packets as non-connectable undirected advertising (ADV_NONCONN_IND).

iBeacon packet structure

  • After 9 bytes of constant preamble, the Proximity UUID, Major and Minor values are transmitted.

  • UUID is 16 bytes long, Major and Minor are 2 bytes long. Together they form an ID for your iBeacon. Mobile devices recognize which Beacon they approach on the basis of these values.

  • The final byte is the packet is used to calculate distance from the iBeacon. It represents RSSI value (Received Signal Strength Indication) measured at 1 meter from the iBeacon. The value of this byte changes automatically if the user changes the transmission power (Tx power) for the iBeacon, but it's also configurable if a user wants custom calibration for each beacon and Tx power level.

Byte offset

Default value

Description

0

0x02

Data length – 2 bytes (constant preamble)

1

0x01

Data type – flags (constant preamble)

2

0x06

LE and BR/EDR flag (constant preamble)

3

0x1a

Data length – 26 bytes (constant preamble)

4

0xff

Data type - manufacturer specific data (constant preamble)

5

0x4c

Manufacturer data (constant preamble)

6

0x00

Manufacturer data (constant preamble)

7

0x02

Manufacturer data (constant preamble)

8

0x15

Manufacturer data (constant preamble)

9

0xf7

Proximity UUID 1st byte

10

0x82

Proximity UUID 2nd byte

11

0x6d

Proximity UUID 3rd byte

12

0xa6

Proximity UUID 4th byte

13

0x4f

Proximity UUID 5th byte

14

0xa2

Proximity UUID 6th byte

15

0x4e

Proximity UUID 7th byte

16

0x98

Proximity UUID 8th byte

17

0x80

Proximity UUID 9th byte

18

0x24

Proximity UUID 10th byte

19

0xbc

Proximity UUID 11th byte

20

0x5b

Proximity UUID 12th byte

21

0x71

Proximity UUID 13th byte

22

0xe0

Proximity UUID 14th byte

23

0x89

Proximity UUID 15th byte

24

0x3e

Proximity UUID 16th byte

25

xx*

Major 1st byte (randomly generated)

26

xx*

Major 2nd byte (randomly generated)

27

xx*

Minor 1st byte (randomly generated)

28

xx*

Minor 2nd byte (randomly generated)

29

0xb3

Calibrated RSSI@1m (for TX power level 3)

* - random values

iBeacon setting parameters

Proximity UUID

Main iBeacon identifier. This column accepts only universally unique identifiers (UUID) in their canonical format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Default value is f7826da6-4fa2-4e98-8024-bc5b71e0893e.

Major & Minor

Secondary iBeacon identifiers. They both accept unsigned 16-bit integers, which means you can enter numeric values from 0 to 65 535. There is no default value for either of them. If you don’t specify yours, they will be randomly generated for each beacon. Combination of UUID, Major and Minor should be unique across all of your iBeacon beacons

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