Is it possible to connect SQL Server via internet without opening port

Question

Is it possible to connect SQL Server via internet without opening port like teamviewer software ?

 

When installing the software to connect SQL database over the internet, I have to declare to open the port to get data. I want to make this installation simple, I can rewrite the SQL Server data connection without opening the same port like temview software or Ultraview software? If so how would the code be written or there is a sample for this case ?