When two EchoVNC users connect to each other via a packet
relay server, any firewalls or routers on the user-side of the
connection see all of the Internet traffic as "outgoing". None
of the new connections appear to be "incoming", which any
firewalls or NAT'ing routers are there specifically to prevent.

Which is all to say, if you use EchoVNC to make your VNC
connections, you won't have to worry about making any
"port forwarding" adjustments anymore.

You also won't need to worry about your partner's IP address
anymore. An EchoVNC connection uses whatever "nicknames"
or aliases the users choose. So you can make an EchoVNC
connection to "Bob'sOfficePC" rather than "66.123.20.58".
That's progress.