The server doesn't support that at the moment, and I see why that's
potentially a problem with '-maxconnections 1' (because, since
-maxconnections is implemented at the socket level, the TCP connection
that is held open while the authentication dialog is open counts toward
the connection limit.)  -rfbwait just specifies the maximum amount of
time that the server should wait for a network read or write to
complete.  The problem is that, when the viewer's authentication dialog
is open, the server isn't waiting for a read or write to complete.  It's
just sitting idle until the viewer sends it the expected authentication
credentials, and the RFB protocol doesn't require that those credentials
be sent in a timely manner.

TigerVNC has a parameter called "IdleTimeout" that drops a connection
after a specified period of inactivity.  That effectively prevents an
open VNC viewer authentication dialog from holding open a TCP connection
to the server indefinitely, but the problem with IdleTimeout is that it
doesn't just apply to authentication.  If, for instance, you specify
IdleTimeout=60, the VNC connection will be dropped if the user steps out
of the office for a minute.  That's not generally desirable behavior.  I
think the correct solution would be to implement an authentication
timeout-- to specify that, after the server enters the authentication
state for a particular connection, authentication must complete within a
specified period of time or the connection will be dropped.  I'm happy
to implement that feature as a funded development project.  Contact me
offline for an estimate if you are interested in pursuing that.

On 6/23/20 5:39 AM, Andrew wrote:
> Thank you for the reply. I am in progress of updating to 2.2.5. I do have One 
> follow-up question about the connections: if a user on the client machine 
> brings up the login prompt but does not enter any credentials, does TurboVNC 
> support a way to drop the connection after a period of time? I looked through 
> the man page for Xvnc and tried a couple of options like “-rfbwait” but it 
> didn’t seem to do what I wanted. I am able to achieve this behavior with 
> custom bash scripts, but if Turbo supports this natively that would be ideal. 
> There was a similar question asked a year or so ago, but there did not seem 
> to be a resolution reached at that time. Thank you again for your time. 

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