ios – How does Airdrop use Bluetooth LE

I do know apple by no means printed the main points of how does Airdrop works, however there are various analysis defined the essential logic for Airdrop: BLE + peer to see wifi.

References:

https://weblog.cryptographyengineering.com/2024/01/11/attack-of-the-week-airdrop-tracing/
https://www.linkedin.com/pulse/how-does-apple-airdrop-works-when-you-connected-same-wifi-kulatunga-khvuc/

Based mostly on the articles above, the BLE (close by gadget discovery) circulation seems like this:

1. File sender begin broasting an ID, e.g “Hey, I am [email protected], I would prefer to ship information”
2. File receiver receives it, checks if this sender ID and its privateness setting, if permits the sender to ship (both setting is Everybody, or the sender is inside receiver’s contacts), construct BLE connection and reply again its title
3. File sender will get the names for all receivers close by from step2, and present these customers on the Airdrop web page
4. As soon as person faucets on a person, sender begins the peer-peer wifi and ship obligatory wifi setting data to that receiver
5. Receiver will get the wifi data, construct peer-peer wifi connection
6. Begin file transferring

Based mostly on this circulation, and my understanding for BLE, the file sender would be the Peripheral (as a result of it’ll begin with broadcasting) and the file receiver would be the Central.
If that’s the case, then which means the Peripheral might be related to a number of Centrals when there are a number of receivers showing on the sender display.

However primarily based on my analysis, peripheral CANNOT hook up with a number of centrals.
So that may result in one other end result, which implies the file sender can solely be the central.

So my query is:

If the file sender is the Central, how can the sender begins with broadcasting its ID so receiver
can use it to test if its inside contacts? And what is the course of above ought to seem like?

Thanks upfront.