Sending packets internally from a node

Good Morning All,
Hope every body is fine :)
I have a few questions, i will be really thankful if some body can please
guide me, i am stuck and feel like i am in no mans land or on mars :(
I want to send a copy of each packet received at one node (say X1) to
another node (say X2).  I have the reference of X2 inside X1, I have
studied a lot of stuff for this purpose but i am unable to find an entry
point to start implementation :(

2ndly, is there a way to find out (using C++) that X1 is in range of X2?


Thanking you in advance, please somebody at least give me a hint.


Warm Regards,
Zubair Ahmed Khan