Commetrex, Inventor of TerminatingT.38, Announces Fax Triangle for Enterprise Fax

Roswell, GA, February 28, 2006 – Commetrex Corporation, well known for its innovations in fax technology, including the invention of terminating T.38, has announced the “Fax Triangle,” licensed technology that it bills as providing unprecedented functionality to the enterprise system developer.


Today’s enterprise servers are being designed to inherently support not just PBX functions, but voice and fax messaging. Frequently, voice support extends beyond messaging to include conferencing and voice-based information services (IVR). Fax support goes beyond traditional fax-server functions to include least-cost routing. Commetrex says its Fax Triangle provides unprecedented support for least-cost-routing and terminations in systems that support both PSTN and IP networks.


Using one leg of the Fax Triangle, the IP-networked distributed enterprise can use T.38 fax relay to send faxes in real time between office fax terminals without them being routed over the PSTN. The second leg of the triangle allows the system to terminate faxes between the server and both internal or PSTN-connected fax terminals. The third leg uses Commetrex’ TerminatingT.38 to terminate (send-receive) faxes that can be routed over the IP network.


For remote gateways that support T.38, the call stream is routed through the T.38 fax protocol engine. Gateways that do not support T.38 resort to what is known as “G.711 pass-through”. In G.711 pass-through the analog stream is packetized into an RTP stream, so it must be modulated/demodulated by analog modems, which are also included in the Commetrex package.


Cliff Schornak, Commetrex’ CTO, explained, ”A dual-transport-capable system can send-receive faxes from any PSTN-connected fax terminal or any IP gateway. However, in least-cost-routing applications, the user may wish to route the fax through the system to a G3 fax terminal located either “behind” the system (on premises) or out to the local PSTN, requiring fax-relay capability. In this case, the fax media stream is not terminated into the Fax Triangle’s T.30 protocol engine. Instead, it is sent to the T.38 relay engine. From there it is routed through analog modems and onward to the intended destination.


Fax Triangle supports the following functions (or sides to the Triangle):

  • T.38 (IP) fax send-receive (side A),
  • T.38 fax relay (side B) and
  • PSTN (analog) fax send-receive (side C)

About Commetrex


Commetrex Corporation develops and markets enabling technologies designed to shorten the time to market and reduce the development cost of integrated-media telecommunications equipment. Long known for its market-leading fax and other licensed technologies, Commetrex has recently completed a multi-year development effort to offer the equipment developer middleware software products and a media-stream framework, plus a comprehensive line of PCI and CompactPCI DSP-resource and network-interface boards.