VNC4 accepts connection 5900 but refuses 5901
jnw "at" realvnc.com
Tue Jul 20 16:09:00 2004
I'm afraid your understanding of TCP is incorrect.
When a service listens on a particular port, any number of connections can
be made by clients of that service, to that port, from any number of hosts,
within reason. How many clients the particular service chooses to support
is a different matter, of course.
Wez @ RealVNC Ltd.
James, correct - VNC on Windows.
I had assumed (mistakenly it appears) that because VNC was using tcp (versus
udp) that as soon as one viewer had connected that port 5900 would be
dedicated to that connection ie. a point to point usage. This was further
reinforced when I looked into the ssh tunneling techniques to find that only
one port needed to be mapped for VNC to operate.
I had also assumed that when ssh was involved that the VNC Server and Client
were not negotiating another port to use after session setup because that
would risk going outside the ssh encryption.
If the viewer/server do negotiate a discrete port like 32K I presume ssh
inspects the packets and seamlessly invoke listens on the relevent hosts for
the nominated tcp ports.
Please confirm/explain/elaborate on the points where I still have it wrong.