[Tinyos-help] boomerang lowpower mesh

[Anthony Dern]

Esteemed list members,



I have an application that was done in boomerang v1.4 (same issue if I
upgrade to 1.5). my mote application is based on the standard Delta app from
Moteiv, with some changes to the data packet to include some sensor data. It
is running on TelosB motes (both Tmote Sky and Xbow). the app is built using
"make tmote lowpower,5".  I am reading the sensor and sending the data
packet from each mote every 10 minutes. Typical system of 80-100 motes.
(though I see the same issues with a test system of 12 motes)



I am using a Moteiv Tmote Connect as a gateway. I have a service that I
wrote that runs on a windows machine that connects to the tmote connect,
receives incoming packets, and routes the data to a sql database.



The system seems to work fine (at least acceptable) if all of the motes are
within single-hop distance of the gateway. When I get a network that
actually relies on multihop, the system falls apart, with close to a 50%
packet loss.



My service is recognizing Uart Detect Request packets and sending the proper
response. It also sends a Uart Keep Alive packet every 5 seconds. The
symptom that I am seeing is that I will get packets from the motes normally
for a while, then I stop getting packets from all but mote address 0 (on the
gateway) this situation will continue for a while then I start getting
packets normally for a while again. It seems to be acting like node 0 on the
gateway is losing its "base station status" and all of the packets being
transmitted by the other motes are going into the ether.



One concern that I have is that even though I am sending the Uart Keep Alive
message, I will continue to get Uart Detect Request packets from node 0. As
I understand it, this should not be happening.



I should also note that I was sent several patches by Rob Szewczyk. These
patches replace files in the CC2420Radio, MultiHopLQI, netsync, and sp
directorys at \opt\moteiv\tos\lib. These files were sent to me as fixes for
an earlier lowpower mesh issue. They were not incorporated into the 1.5
version of boomerang.



Also to note, sometimes when the communication "comes back" I get a number
of packets that were queued in the network somewhere.



Thank you in advance for your time. I appreciate the help I hope I have
included enough information.
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