[Tinyos-help] about CTP

[Omprakash Gnawali]

On Wed, Mar 12, 2008 at 6:50 AM, jiwen zhang <zhangjiwen029 at gmail.com> wrote:
> Hello all :
>    as we know , ACKs is on link layer , that is to say if a mote receives a
> packet , it will return an ACKs to the sender. but how to ensure data
> transmission in network layer ? for exaple , in a mulitihop sensor network ,
> a mote receives a packet and returns the ACK. maybe it has received many
> packets waiting to send and the queue is full , so it has to discard it , so
> the packet may not get to Root(in CTP) . (i don't know if i say it clealy ,
> in short, i want to know whether there is a  route layer ACK in CTP)

No, there isn't.

>   how the problem is solved in CTP ?

If the packet was not acknowledged (you can look at the ack bit of the
packet), you retransmit.

- om_p