VNC Protocol Compatibility

Jason Harris smeger "at" geekspiff.com
Fri Feb 2 22:46:00 2007


How specifically does UltraVNC fail to maintain compatibility with  
the RFB protocol?  From my perspective, it's a VNC server - my users  
connect to it using my client (Chicken of the VNC) and they file  
compatibility bug reports on my client when issues crop up relating  
to UltraVNC.   Walks like a duck, quacks like a duck...

Are you referring to some subtle breaking of the RFB protocol or are  
you talking about something like file transfer?

Jason Harris

On Feb 2, 2007, at 2:30 PM, James Weatherall wrote:

> Steve,
>
> You've both missed the point and are unfortunately mistaken.
>
> It's not a question of "branding", it's a question of protocol
> compatibility.  The UltraVNC project does not retain compatibility  
> with
> the RFB protocol, which is why it isn't compatible with standard VNC
> releases.  By contrast, the TightVNC hobby project has been able to
> proceed, adding custom features to our core system and using their own
> custom protocol elemants while retaining compatiility with the  
> standard.
>
> As far as "branding" is concerned, please bear in mind that VNC is
> developed by RealVNC Ltd.  TightVNC and UltraVNC are projects based  
> on our
> codebase, not "brands" of our software.
>
> I hope this clarifies your misunderstanding of the situation.  Your
> customers will be happier knowing that your products use fully
> VNC-compatible software rather than software that breaks compatibility
> with the protocol!
>
> Cheers,
>
> Wez @ RealVNC Ltd
>
>
>
>
> On Fri, 2 Feb 2007, Steve Bostedor wrote:
>
>> James and everyone else,
>>
>> I agree that it's not  RealVNC 4.x brand compatible but it is VNC  
>> compatible
>> in the sense that it is using a VNC protocol and works with any  
>> VNC that is
>> not the RealVNC brand 4.x base.  That's like saying that it's not  
>> Microsoft
>> Windows compatible unless it runs on Windows Vista.  :)
>>
>> UltraVNC and TightVNC are very popular versions of VNC that are  
>> actively
>> developed and very feature rich thanks to these "hobbiests".  They  
>> should
>> not be ignored simply because they don't use the same code base as  
>> the
>> RealVNC branded 4.x code base.
>>
>>
>> I don't mean to be the annoying accuracy cop here but this  
>> distinction needs
>> to be clear.  UltraVNC and RightVNC are RFB compatible VNC servers  
>> that
>> branch from and improve upon the original 3.x code base while  
>> maintaining
>> backwards compatibility (unlike the 4.x code base).
>>
>> Steve Bostedor
>> Bozteck Solutions
>> http://www.bozteck.com
>>
>>   ------------------------------------------------------------------
>>    Take control of your network with
>>    VNCScan Enterprise Network Manager
>>    Download: http://www.vncscan.com
>>   ------------------------------------------------------------------
>>
>>
>>
>> -----Original Message-----
>> From: James Weatherall [mailto:jnw "at" realvnc.com]
>> Sent: Friday, February 02, 2007 1:01 PM
>> To: 'Steve Bostedor'; vnc-list "at" realvnc.com
>> Subject: RE: Hitachi-ZYWRLE Encoding Number (was RE: Introduction  
>> of New VNC
>> codec)
>>
>> Hi Steve,
>>
>> As I pointed out in my original response, the problem with them  
>> having
>> patched against the UltraVNC hobby project is that that's not
>> VNC-compatible.  Better to product patches against something VNC- 
>> compatible,
>> or, better still, the standard VNC codebase, if you want people to  
>> be able
>> to use it!
>>
>> Cheers,
>>
>> Wez @ RealVNC Ltd.
>>
>>
>>> -----Original Message-----
>>> From: Steve Bostedor [mailto:sbostedor "at" vncscan.com]
>>> Sent: 02 February 2007 17:29
>>> To: 'James Weatherall'; 'Hitachi Systems & Services, Ltd.';
>>> vnc-list "at" realvnc.com
>>> Subject: RE: Hitachi-ZYWRLE Encoding Number (was RE:
>>> Introduction of New VNC codec)
>>>
>>> Why not patch against both?  The UltraVNC and TightVNC
>>> flavors are just as
>>> popular as RealVNC.  Why limit yourself to just one version of VNC?
>>>
>>>
>>> Steve Bostedor
>>> Bozteck Solutions
>>> http://www.bozteck.com
>>>
>>>   ------------------------------------------------------------------
>>>    Take control of your network with
>>>    VNCScan Enterprise Network Manager
>>>    Download: http://www.vncscan.com
>>>   ------------------------------------------------------------------
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: vnc-list-admin "at" realvnc.com
>>> [mailto:vnc-list-admin "at" realvnc.com] On
>>> Behalf Of James Weatherall
>>> Sent: Friday, February 02, 2007 7:31 AM
>>> To: 'Hitachi Systems & Services, Ltd.'; vnc-list "at" realvnc.com
>>> Subject: Hitachi-ZYWRLE Encoding Number (was RE: Introduction
>>> of New VNC
>>> codec)
>>>
>>> Hi Noriaki-san,
>>>
>>> I've had encoding number 17 allocated to Hitachi ZYWRLE - using this
>>> encoding number will ensure compatibility with standard VNC and
>>> VNC-compatible releases.  The next release of the VNC codebase will
>>> therefore include an encoding "place-holder":
>>>
>>>   const int encoding3rdPartyHitachiZYWRLE = 17;
>>>
>>>>> I note that you have a version of the UltraVNC hobby project
>>>> patched with
>>>>> your scheme.  Since the UltraVNC project is not
>>>> VNC-compatible, you will
>>>>> need to switch to a VNC-compatible codebase if you want to
>>>> provides VNC
>>>>> viewers & servers with your custom encoding.
>>>>
>>>> You say that I need to make patch for RealVNC server, don't you?
>>>> (Sorry to my poor understanding to English...)
>>>
>>> Not necessarily - which particular VNC version, or VNC-based
>>> software, you'd
>>> like to patch your encoding against is entirely up to you.  I'd  
>>> would
>>> recommend either patching against the standard VNC release, or a
>>> VNC-compatible project such as TightVNC.
>>>
>>> Regards,
>>>
>>> --
>>> Dr James Weatherall
>>> Chief Engineering Officer - http://www.realvnc.com - RealVNC Ltd
>>> _______________________________________________
>>> VNC-List mailing list
>>> VNC-List "at" realvnc.com
>>> To remove yourself from the list visit:
>>> http://www.realvnc.com/mailman/listinfo/vnc-list
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>
> -- 
> Dr. James "Wez" Weatherall
> --
> Chief Engineering Officer
> RealVNC Ltd. - The home of VNC - http://www.realvnc.com
> _______________________________________________
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> VNC-List "at" realvnc.com
> To remove yourself from the list visit:
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