MikroTik

I want to know if i can do s/d nat with my mtk but without changing the ports used, only the ip address, that is for putting an sip telephone in my private network (wich uses random ports), using only one private IP address (doing NAT).

certainly.
you can nat and enter 0-65536 for ports.

if i put that in to port my mkt doesn´t change the original port? sip works with random ports, so i want to keep the original port