[ns] [IEEE 802.15.4] About Pending Packets at Node's Queue?

Hi everyone! My question is about IEEE 802.15.4. 1: How to know about the total packets in a node queue? 2: How to know about the pending packets after when the node transmit the packets? For example: If a node has 50 packets in its queue and transmitted 40, so 10 are pending in its queue, whi

[ns] End-to-End Delay at MAC layer

Hello every one, I want to calculate end to end delay at mac layer [IEEE 802.15.4].