Does an iBeacon have to use Apple's company ID? If not, how to identify an iBeacon?

Question

According to the iBeacon spec, iBeacons have to broadcast 0x004C as the company ID in the advertisement's manufacturer data. 0x004c is Apple's company ID as assigned by the Bluetooth SIG.

I'm confused by this because other than the company ID, there doesn't seem to be any other data that definitively identifies a BLE device as an iBeacon. The next two bytes fixed to 0x02 and 0x15 and the rest is configuration dependent.

At one point I figured that if the first four bytes of the mfg data are 0x4c 0x00 0x02 0x15, then it is an iBeacon. Then, I found iBeacons that used other company ID's. I have Nordic Semiconductor iBeacon samples, for example, that use 0x59 0x00, which is Nordic's company ID.

Even if I look to make sure the 0x02 and 0x15 are where they are, and that the device is unconnectable, and the mfg data is the exact length, this doesn't seem to be definitive.

How to definitively identify an iBeacon?

Answer 1

You can see the byte sequence of an iBeacon transmission in my answer here.

The bottom line is that the exact header (including the company code) must be as specified for iOS to interpret an advertisement as an iBeacon transmission and to return the results using iOS CoreLocation APIs. If a different company code is used, it will simply not be detected by these APIs. Even though different companies manufacture beacons meeting the iBeacon specification, the all use the Apple company code.

The fact that some chip manufacturers give example code using different company identifiers (e.g. Nordic Semiconductor 0x59 0x00) may just be a way of getting around intellectual property restrictions. Apple insists that those who market their products as iBeacon compatible sign an agreement saying they will not disclose the specification. Nordic may be attempting to comply with this agreement by changing the company identifier in its sample code. Regardless of the reason, the fact remains that iOS devices will not interpret such a transmission as an iBeacon packet with an unexpected company code.

Answer 2

Since there is no standard defining a "beacon", different manufacturers have their own advertisement formats. Therefore you will have to make up a list of advertisement patterns you want to snap up. Each company defines what their data means so just looking at the first 2 bytes in the manufacturer data does not work since some company might use the prefix 0x02, 0x15 for something else.

Answer 3

You can download the iBeacon specification here (requires accepting licence agreement).

The specification states that the Company ID:

Must not be used for any purposes not specified by Apple.

Using these 2 bytes for their intended purpose of identifying the manufacturer is acceptable. Using these 2 bytes to broadcast additional information would probably fall outside of the licence agreement.

The information contained in the spec should be enough to help you. If you see a length of 0x1A, and 0x02, 0x15 in their respective places, it is most likely an iBeacon packet.