[Tinyos-help] Collection: Loosing Connection to a Node

[Omprakash Gnawali]

On Sun, Apr 6, 2008 at 2:00 PM, Bulut ERSAVAS <bfersavas at gmail.com> wrote:
> Hi Phil,
>
> Thank you for your comments as well. Our application is based on
> MultihopOscilloscope with no significant changes. We added LPL
> functionality, would this cause any issues (sleep interval is 1000ms)? In
> addition, we inserted Dissemination capability.

We have done some testing with CTP+LPL. The problem is the root is
generating beacons every second and if you are using LPL with a sleep
interval of 1000ms, the nodes are probably not sleeping. Are the nodes
sleeping much at all? My guess is, they are not because the root is
keeping the medium busy all the time.


>
> If, let's say, the RSSI worsens by about 10dB and a node looses its
> neighbor; it will be able to re-discover the neighbor if RSSI get backs to
> normal, right?
>

Yes, that is what should happen. When you observe this problem next
time, you can snoop the packets. The CTP beacon is encapsulated in a
LEEP frame so you should be able to see if the node has any neighbor
or not...

If you reboot and the problem goes away, CTP has a bug...

What platform/radio are you using?

To answer your earlier question, yes, we do observe fewer packets from
nodes farther away, but we are talking about a difference of less than
1% between nodes that are 1 hop and 4 or 5 hops away, in our
experimental scenarios. Yours is different, of course.What kind of
loss are you seeing?

- om_p