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Protocol 3.3?

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dframeli62
Posts: 2
Joined: 2019-12-06 15:09

Protocol 3.3?

Post by dframeli62 »

I have a number of equipment simulators that internally have their own Protocol v3.3 compliant VNC server.

As such, I can remotely access the simulators interface using VNC.

I can, for example, VNC into a simulator using RealVNC v4.5.1… (I’m prompted for a password, I enter it and I’m in)

And, I can VNC into the simulator using UltraVNC v1.1.0.2… (I’m prompted for a password, I enter it and I’m in)

*But*, for some reason I cannot VNC into the simulator using UltraVNC v1.2.2.4 or 1.2.3.0 (or any version of uvnc released since v1.1.0.2…)… (I’m never prompted for a password, and it takes a very long time before the attempt eventually fails, and ultimately, I never can VNC into the simulator using a recently released version)

I tried matching my uvnc v1.1.0.2 and v1.2.2.x/v1.2.3.0 settings, but the later versions just don’t seem able to connect.

Can anyone tell me why an older revision of uvnc works, but later revisions cannot?

If so, can you recommend any setting changes I could make that would allow me to use a newer revision?
Last edited by dframeli62 on 2019-12-07 13:54, edited 1 time in total.
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Rudi De Vos
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Re: Protocol 3.3?

Post by Rudi De Vos »

Uvnc use rfb 3.8 protocol but should be backward compatible
The older version used rfb 3.3

We did some tests with our own old servers, do you now any windows vnc server that can be used to simulate the issue ?
dframeli62
Posts: 2
Joined: 2019-12-06 15:09

Re: Protocol 3.3?

Post by dframeli62 »

These equipment simulators are running an older version of RedHat Linux.

I don't know of any Windows based servers that uvnc does not work with (old or new version).
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Rudi De Vos
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Re: Protocol 3.3?

Post by Rudi De Vos »

Tested with an old uvnc server 3.3 from 2005 and this works.
Possible they use some rfb3.3 dialect, need at least something to simulate it to be able to check the code.
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