Software serial and new soft serial not working

Hello,

I am working with the Due. The newsoftserial examples do not compile and say that it has been moved to the core and now software serial should be used. Now I say #include<SoftwareSerial.h> and it says no such file or directory. Some please let me know as to how I can overcome this issue.

How many hardware serial ports does the Due have? Why do you also need SoftwareSerial? Why do you assume that SoftwareSerial is compatible with the Due?