Subject: [Drip] Authentication Formats Follow-Up

From: "Wiethuechter, Adam" <[email-masked]>
Date: Fri, 31 Jul 2020 08:24:42 -0400

All,

Thanks to everyone who participated yesterday in the meeting! There was
some great discussion with Stu's presentations that I hope to see more of
here.

I wished to send an email following up my slides as I went through them at
warp speed right at the end and felt bad about leaving everyone behind and
not getting the chance for clarification on anything I said. Also I feel
like there were some great talking points I couldn't get to.

One slide I did really go past was slide 14 that discusses the FEC
justifications. While no actual flight testing has been done with this
(just bench testing from code I wrote on both sides - so bad protocol
implementation practice), it is being planned and prototyped on the
receiver end soon by another member of the AX team. We believe that its
inclusion will improve the timings and distances of Bluetooth 4 from slide
3.

So this thread is open to any questions, comments or concerns regarding the
draft and my presentation slides (attached for ease of access).

-- 
73's,
Adam T. Wiethuechter
AX Enterprize, LLC

---

From: Robert Moskowitz <[email-masked]>
Date: Fri, 31 Jul 2020 09:00:15 -0400

On 7/31/20 8:24 AM, Wiethuechter, Adam wrote:
> All,
>
> Thanks to everyone who participated yesterday in the meeting! There 
> was some great discussion with Stu's presentations that I hope to see 
> more of here.
>
> I wished to send an email following up my slides as I went through 
> them at warp speed right at the end and felt bad about leaving 
> everyone behind and not getting the chance for clarification on 
> anything I said. Also I feel like there were some great talking points 
> I couldn't get to.
>
> receiver end soon by another member of the AX team. We believe that 
> its inclusion will improve the timings and distances of Bluetooth 4 
> from slide 3.

I want to add some discussions Adam and I have had on timing.

First a UA moving at 60MPH = ~42FPS.  So you have 7s warning with BT4 
and ~42s with BT5.

Now this is bad in his worst timing of 45s and even 2s eats up critical 
time to respond, but things are really not so bleak. Adam's code is in 
Python and quite removed from the actual radio driver.  Let's look over at:

See: 
https://www.bluetooth.com/blog/exploring-bluetooth-5-how-fast-can-it-be/

One BT 4 packet takes 80 + 150 + 328 + 150 µs = 708µs

I do not think BT has an cts/rts like wifi.  So the UA COULD stream the 
10 auth frames and:

So 10 take 7.08ms.  Closer to radio coding will greatly reduce timing..

Though someone may make a recommendation for some timing, maybe one 
frame's worth between the packets.  We would need to ask some BT RF 
experts about this.

>
> So this thread is open to any questions, comments or concerns 
> regarding the draft and my presentation slides (attached for ease of 
> access).
>
> -- 
> 73's,
> Adam T. Wiethuechter
> AX Enterprize, LLC
>
>

-- 
Standard Robert Moskowitz
Owner
HTT Consulting
C:248-219-2059
F:248-968-2824
E:[email-masked]

There's no limit to what can be accomplished if it doesn't matter who 
gets the credit