[Tinyos-help] Re: Is it possible to change a collection tree's root?

[Philip Levis]

On Aug 1, 2007, at 4:38 AM, Hugo Sousa wrote:

> I've even tried changing the CtpRoutingEngineP parameters in CtpP,
> like Phillip said in another thread, but still doesn't work. Isn't CTP
> prepared to handle tree root changes? What about topology changes?

In theory, it should handle tree root changes and topology changes  
fine. We've certainly tested the latter in testbeds, and I've tested  
the former in simulation. All a node does is try to route through the  
neighbor that has the lowest cost route. The only possibility I can  
think of is that nodes which are close to the old root are forming  
large routing loops as they try to find a route. But this would  
increase their route cost, causing them to be unattractive as next hops.

Do you have a wired backchannel? CTP has extensive logging  
information that it can send to the serial port, with which you can  
figure out exactly what's going on.

Phil