[Tinyos-help] Doubts on Base station tutorial and AM type

[Nithin Dara]

Hi all,

In the base station tutorial, when a packet is received from the radio, the
mesg is copied into the queue, and then later a it is sent over the serial
with the same id of the radio packet. Why should it  with the same id?

I understand the sender and receiver should have the same id, but why the
radio's receiver and serial's sender should be the same?