You may add a line to /etc/networks so that your VPN will get a symbolic name. For example:
You may add this line to /etc/services. The effect is that you may supply a ‘tinc’ as a valid port number to some programs. The number 655 is registered with the IANA.
tinc 655/tcp TINC tinc 655/udp TINC # Ivo Timmermans <email@example.com>