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Loopback Listener

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M38a1
Posts: 2
Joined: 2014-05-19 14:27

Loopback Listener

Post by M38a1 »

Dear experts,

i have done a SC-setup with a repater in the middle. This means that winvnc.exe calls the repater and also the viewer.exe ... was a kind tricky to find the right commandline parmaters and order but now it works.

The challenge is that as well the connection form the viewer PC to the repeater and also from the server to the repeater is useing a TCP portforwarding with a loopback listener.

This means that 127.0.0.1:5901 looks to the viewer as if this would be the repeater - and 127.0.0.1:5500 looks to the server as if this is the repeater.

I didn't expected that but VNC repeater seems to have a problem if you use the loopback. Is there any version that fixes this. More or less it's the same as if there is a SSH connection on both sides.

If my findings are correct the viewer needs port 5901 TCP and winvnc the port 5500 TCP ... no UDP - no other ports ... correct ?

Thanks for your help
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Rudi De Vos
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Re: Loopback Listener

Post by Rudi De Vos »

Also Check
http://www.uvnc.eu/download/1210/Repeater.pdf

I try to understand what you want todo.
If you don't have a dedicated server, then you need to forward 2 ports
On the nat router you tell to forward 5901 and 5500 to the PC running the repeater...

In case you also want to run the viewer on that pc, you connect the viewer to
[v] proxy/repeater 127.0.0.1:5901
M38a1
Posts: 2
Joined: 2014-05-19 14:27

Re: Loopback Listener

Post by M38a1 »

Thanks for your answer ... but the issue is solved.

It took incedible 6 days until my question was accepted by a moderator so I was too impatient and worked on and solved it yesterday.

What happens in my solution is that there is a secured connection with two-factor authentication on the viewer and the server side which is done by pluging in a USB key. The VNC repeater is on a hosted server and the ID is stored as a variable.

So no matter how the PC is connected to the internet (direct or proxy) the tunnel is established and the VNC server is autolaunched with the correct command line parameters - simply by pluging in the "Server USB".

Same on the viewer side.

This allows to take over your working PC from everywhere no matter how you are connected to the internet and no matter if you are allowed to use RDP or not. You can run the connection without any configuration or local files on both sides and that's a kind of "cool stuff".

But as said that's up and running now so the only question I have no answer yet is:

Is there limit in the number of connections who can be used at the same time through a VNC repeater ?

Thanks Michael
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Rudi De Vos
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Posts: 6832
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Re: Loopback Listener

Post by Rudi De Vos »

Sorry, was a week on holiday. Uvnc is still a hobby.

The repeater limit is the bandwidth, there is no software limitation.
The repeater just pass data from A to B and B to A, he doesn't read the content. Using a heavy encoder put more load
on server/viewer and less on the repeater.
Sainsuper
40
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Posts: 96
Joined: 2008-04-02 10:47

Re: Loopback Listener

Post by Sainsuper »

hi M38a1, your soluzione is Intereting. How do you do to tcp port forwarding? With a Ssh server ?
Regard.
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