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About us

PSGw testimonial:
"...I am delighted to announce that the interface between Skype and SIP works like a charm, and at the remarkably good voice quality often reported by Skype users. We run PSGw with single Skype account to receive calls and route them to our telephone operator, to be forwarded on our Asterisk PBX to the intended recipient (or conference box). Source:
Read all testimonials - H.239 details

H.239 details provides contract development for products that requires H.239 support.
Contact Roman Skvirsky with your requirements for a rapid response and aggressive pricing.


   1. General description
   2. General technical specifications
   3. Compatibility
   4. Sample application

1. General description: H.239 is a feature of H.323 recommendation. H.239 describes how to send additional video stream in a parallel to main video picture.
For example, it is possible to see speaking person within main video screen and see his (or her) desktop with diagrams or screenshots.
Few vendors (Polycom, Tangberg) supports H.239 recommendation in their H.323 stacks. offers H.323 stack with H.239. We can provide either H.323 component or application with H.323 and H.239 or deliver full H.323 stack so you can build own H.323 application with H.239 features.

Contact Roman Skvirsky for details.

2. General technical specifications

H.323 stack features


  • G.711-uLaw-64k
  • G.711-ALaw-64k
  • Speex
  • G.726
  • iLBC
  • GSM
  • G.723.1
  • H.261
  • H.263

ITU Recommendations in stack

  • H.225
  • H.245
  • H.450
  • H.224
  • H.460
  • H.239

3. Compatibility

All major H.323 stacks:
  • Cisco
  • Polycom
  • Tandberg
  • RADVision
  • Alcatel
  • OpenH.323
and many others.

4. Sample H.323/H.239 application

Sample H.323/H.239 demonstration application is available here:
Unpack this simple application and place or accept H.323 call to it - you can view or send H.323 and H.239 video streams.
Latest news

February 22, 2010.
New version of H.323/SIP SoftPhone released
February 21, 2010.
New version of H.323/SIP MCU (Conference Server) released
October 2, 2009.
Press about us
May 18, 2009. is one of the Top 10 Finalists of Cisco Developer Contest !!!
March 20, 2009. introduces H.323/SIP Video Softphone for PDA - Windows Mobile 2003/5.0/6.0 Video SoftPhone for SIP and H.323 networks
July 14, 2008. introduces "Web-2-Phone" - Flash-based phone with SIP/H.323/Skype support
July 19, 2007.
PSGw 3.5 (SIP version) demo released
February 1, 2007.
PSGw for Linux 1.6 (SIP version) released
January 1, 2007.
Merry Christmas and Happy New Year!
July 24, 2006.
PSGw for Linux 1.5 (SIP version) released
July 18, 2006.
PSGw 3.5 Standard and Pro now has unique feature - arbitrary SIP destination!
July 1, 2006.
PSGw 3.3 Pro (SIP and H.323 version) allows to set SIP and H.323 DTMF type
June 29, 2006.
PSGw 3.3 Standard (SIP version) allows to set SIP DTMF type
June 20, 2006.
PSGw for Linux 1.2 (SIP version) is released for beta-testing!
May 18, 2006.
Updated PSGw has codec management feature and prefix for Skype username


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