Re: [GnomeMeeting-list] Encrypted video

[Craig Southeren <craigs postincrement com>]

On Mon, 05 Jan 2004 23:59:24 -0800
Derek Simkowiak <dereks realloc net> wrote:

>      Hello all,
> 	I am seeking advice for a proof-of-concept project.
> 
> 	I want to build a network of webcam users who can video chat together, but with all traffic encrypted.

..deleted

Derek,

You pose an interesting question :)

While there may be a single commercial products that meets your needs,
if you want to use Open Source then you will almost certainly need to
use a collection of programs.

If I wanted to solve this problem for myself, I would use the following:

a) Use a standard client like GnomeMeeting to be the video and audio
endpoint. Problem solved :)

b) To do the encryption, you will need to use a H.323 proxy (and
possibly a gatekeeper) that can combine the video and audio streams into
an encrypted channel and then demux at the other end. I'm not aware of
anything that can actually do this, although I vaguely remember that
GnuGK might have some capabilities in this regard. You may want to check
out http://www.gnugk.org for more information. (For what it is worth,
this exact feature is on my To Do list for my own routing gatekeeper :)

c) For a multi-person conference, you will need an MCU. The only MCU I
know of is OpenMCU, and it is not production ready code (see my blog at
http://users.tpg.com.au/adsl87w7/blog/ for more information)

So if I was going to solve this problem, I would have some code to write
and debug. Oh dear :(

In your email, you dismiss using a general purpose VPN to solve the
problem, but I would not be so quick to do this. Firstly, unless I am
mistaken, the only common point between all of the machines is the
central server. If that box is locked down, viruses/worms etc cannot be
spread to other machines. There are a few Open Source VPN products, but
I have had a lot of success with a program called CIPE. See
http://sites.inka.de/sites/bigred/devel/cipe.html for more information
on this.

In relation to NetMeeting, that particular program implements
encryption and authentication via T.120. As far as I know, those methods
are only implemented by high-end video conferencing equipment. It is NOT
based on H.235

   Craig



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 Craig Southeren, craigs postincrement com http://www.postincrement.com
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