I am   using 6.2.1 version of QNX on cPCI platform. The system I am  developing is a node (in an  IP netwrok) which 
directly gets IP data stream from air interface ( radio communication). This IP packet is to be routed by the node  to  
Internet cloud  through a Packet data Gateway. 
 
To do the above routing I intend to employ NAT ing  in the Node, which will translate the "Source IP address + Source 
Port number"  combination to  a new port number. The node will re-send  the received IP packet after modifying the 
Source IP address field in the received packet to that of the IP address of the Node itself and  the Source Port 
replaced with the newly translated  Port Number. 
 
However this needs lower level control of the packet. Normally we use socket programming APIs for IP communication, 
which will not be useful here. I have gone through the programmer's manual to  some  extent but have not been able to 
locate the APIs which will allow us to do NAT. Can some one help with inputs on how the above task can be achieved.  Are
 there APIs available at this level?
 
Help in this regard will be highly appreciated.
Regards,
Praveen.