[Tinyos-help] [TinyOs 2.x] ACK Bug?

[Michael Schippling]

Yup. Life is much easier in simulation.
thx
MS

Philip Levis wrote:
> 
> On Jan 2, 2009, at 11:19 AM, Michael Schippling wrote:
> 
>> Hmm...interesting. Why would #2 happen? Message overrun?
> 
> The current (2.1.0) code flushes only when a node receives a packet 
> whose length is longer than the FIFO (128 bytes). Older stacks would 
> flush on additional error conditions.
> 
>>
>>
>> If it was only #1 it would seem that you would have at worst
>> a 1::2^16 chance of a falsely correct CRC and then an even
>> smaller chance of it being the type field that was corrupted.
> 
> You'd think so, but... I'm not 100% sure. There could be other things 
> going on in the radio stack. *shrug* If I had a free day or two I might 
> try to get the bottom of it. But since assuming an L2 ack implies an L3 
> delivery is a bad idea to start with, I made TOSSIM keep this in account.
> 
>>
>>
>> That said, the chance of missing a valid ACK is much greater
>> than getting a false one.
> 
> Yes. False positives are rare, but they happen.
> 
> Phil

-- 
Platform: WinXP/Cygwin
TinyOS version: 1.x, Boomerang
Programmer: MIB510
Device(s): Mica2, MicaZ, Tmote
Sensor board: homebrew