Comment by ChrisMarshallNY | Hacker News Reader

Comment by ChrisMarshallNY | Hacker News Reader

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ChrisMarshallNY

The "LE" is more about behavior, rather than some power-saving tech. It affords low-energy-use behavior. Short bursts, ad hoc connections, small amounts of data, etc. If we make it behave like Classic, it will suck energy like Classic.

I like using BLE, more than Classic (BR/EDR). It's a bit pedantic, getting things set up, but that can be abstracted, fairly easily[0].

If we program for iOS/WatchOS/TVOS/iPadOS, we'll generally be using LE, as Core Bluetooth is designed around LE. Classic is there, but IOBluetooth is only meant for MacOS, and is a private API, on the other platforms.

LE is basically meant for short busts of control information, or small bits of data. Its encryption is pretty good. You can actually have a meaningful dialogue, just using the advertising information, so a connection is not always required (beacons use this).

I have heard that they will be adding some high data-rate stuff to LE, so we may be seeing true LE headphones, in the future.

[0] https://github.com/RiftValleySoftware/RVS_BlueThoth

This is exactly right from my experience in having worked on a few different BLE devices, one of which you've almost certainly used.

If you use it like classic bluetooth, you're going to have a bad time like classic bluetooth. Information in advertising packets (which can be as infrequent as a few seconds) is also used extensively in sensor applications which can last a few years on a coin cell battery.

If you live in the middle ground where you want to maintain connectivity, but sporadically send chunks of data on the order of a few to 100s of k, that's where it gets a bit tricky. BLE is still much better for power than classic in those scenarios, but the protocol isn't really intended for that type of bandwidth, and you might end up with a lot of custom stuff on top.

The extended advertising support in BLE 5 helps there, does it not?

If you're sending data via advertisements, yeah. Otherwise, you want Data Length Extension.

> so we may be seeing true LE headphones, in the future

LE Audio has been worked on for a long time, the last missing pieces have been finalized just about a month ago and the marketing push appears to be beginning around this time. From what I recall they expect the first LE Audio peripherals by the end of the year (but pessimistic me would say it's more likely the middle of next year). High-end phones with Bluetooth 5.2 and Android 13 should already support it.

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