配对蓝牙设备是否有优势？

Question

I have made an app on iOS and Android that can connect to a BLE device. I connect to the "device by service" and things work well.

A customer is asking me why the device is not showing in the list of bonded bluetooth devices. I didn't need pairing to connect because I found code that didn't require it, but now that I think, I wonder :

What would be the benefits to have a paired device ?

Would it connect faster ? Hold connection better ? ...

Answer 1

Security, mainly.

Sending data to a non-paired device requires that the device be discoverable and open to receiving data from random devices. This isn't always the case for reasons of security, and so many devices ship with both disabled.

The attack vector is something like this: you'll always have to pick a device in the list of discovered devices. It's not too difficult to create a device with "<CEO>'s iPhone" as the name and wait until he tries to send the secret memorandum to his iPhone, then intercept it.

Additionally, bluetooth stacks have been known to have vulnerabilities that can be exploited by sending data to the device, which was made more problematic by devices auto-accepting data without confirmation.

Paired devices create a pre-existing relationship between the two, allowing your user to be notified when something out of the ordinary happens. This is always a good thing.

It is indeed also true that not having to go through device discovery (which may take up to a few seconds) improves performance when doing the initial connection setup, but I wouldn't see that as the major reason.