Comment by arcticbull | Hacker News Reader

Comment by arcticbull | Hacker News Reader

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I agree with you, except about Bluetooth LE. LE (4.0) is a totally different protocol than 'classic' Bluetooth (<= 3), and shares no heritage. Nokia came up with the LE spec and dropped it down on the desk at the Bluetooth SIG and told them this was Bluetooth now ("wibree", [1]). The LE family is just a short couple of years old now, not 20.

For many of the tasks you'd want high bandwidth for, you probably want WiFi (or even point-to-point WiFi established over Bluetooth LE like AirDrop). LE is a huge step forward because it distinguishes between the two major use cases (low bandwidth - low power - promiscuous mode vs. high-bandwidth - paired) and allows for the development of standards which meet each use case without compromise. Part of why Bluetooth was pretty garbage before is that its use cases overlapped so heavily with WiFi, but it wasn't allowed to (or ever going to) replace it. This lead to this weird hybrid high-power, middling bandwidth, paired but you-probably-dont-want-it-to-be spec.

LE 2 (Bluetooth 5) addresses some of your concerns by increasing the bandwidth available for LE devices, without compromising on power efficiency.

[1] https://en.wikipedia.org/wiki/Bluetooth_Low_Energy

How do I tell if a device is Bluetooth LE though? It still pairs in the same list as all the other Bluetooth devices and I don't see anything that identifies it otherwise. So it kinda sucks for LE devices to get the "bad rep" because as far as consumers are concerned, LE devices suck as well, they just don't display those same issues all the time.

LE is a different spec and behaves completely different from traditional Bluetooth. People assume Bluetooth 4+ is LE but it's not. If you're pairing with a device in the traditional Bluetooth sense, it's not LE.

... ok, so how do you know you're using LE?

It's easier to tell when you're not using BLE. :)

The Tesla Model 3 uses traditional Bluetooth for phone calls and streaming but the Phone as a Key functionality is BLE. When you walk up to the car and try to open it and the car says FU then BLE isn't working.

When your Xiaomi Mi Band smartwatch hasn't buzzed all day but you pull your smartphone out of your pocket and have 8 missed calls, 100 messages, and 500 emails then BLE isn't working.

When you're at a Tech Conference and the Conference App uses BLE Beacons to help navigate you indoors and it can't determine your location then BLE isn't working.

If you're streaming audio over Bluetooth (i.e. headphones or speakers), you're not using BLE, you're using classic Bluetooth, and none of this matters. BLE didn't have the bandwidth for audio until 4.2, and still doesn't have an audio standard like classic Bluetooth's headset profile.

Bluetooth LE may be only a few years old, but it already has a split between insecure legacy pairing modes that shouldn't be used and actually-decent pairing modes that only work on newer devices.

Yeah if I recall that was due to issues with security if an attacker observed the initial key exchange in 4.0 and was resolved in 4.2 and 5, right?

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