The Commetrex Outlook | May 2014

FaxTap for SIP, Release 2.0 on the Way

There are two versions of FaxTap for SIP: one for the end user that just wants to solve an FoIP problem, and one for the lawful-intercept (LI) OEM. Fax Tap for SIP 2.0, slated for release in late June, includes added features for both types of users.

FaxTap is an FoIP analysis tool that picks up where Wireshark leaves off. Wireshark will display the envelope of the PCM data, give you a SIP ladder, and, if it’s a T.38 call, give you something of a T.30 ladder. But it doesn’t render the image nor does it give you the T.30 ladder for a G.711 call. FaxTap does all of this and much more, including full support for T.38 version 3 with V.34 support. Version 2.0 will be easier to use and remove a hole in the LI OEM version that today the bad guys can sneak through.

For the end user we are adding a GUI to do something about the number of command-line arguments that must be passed in. This means that front-line tech support, in addition to the motivated equipment OEM, can easily take advantage of FaxTap for SIP, a product that is removing the mystery from FoIP call analysis.

As for the LI OEM, we are adding support for NSS/NSF (Non-Standard Facilities and Non-Standard Services). This is a tough nut to crack since NSF and NSS give the two communicating terminals the ability to step outside the T.30 protocol, which governs how standard fax terminals communicate. If the caller recognizes the answering machine’s ID and NSF and wants to utilize a proprietary facility, it may reply with an NSS, at which point FaxTap is in the dark, and must resort to guessing about what is going on.

The biggest guess is what modem is being used. If the two terminals are using a standard fax modem, FaxTap can analyze the frequency components of the data and hope that it gets a match to the signature of a standard fax modem. It will then attempt to decode the image data and then present the data to FaxTap’s image-conversion facility. If the image can be decoded … great. Otherwise FaxTap outputs the decoded binary file.

The same process is used to track multiple transitions from voice to fax to voice, etc, which the T.30 standard also supports.

If you are an LI OEM, why not add support for fax since FaxTap makes it easy and affordable? So, look into FaxTap for SIP 2.0. Interested? Email us or call 770-449-7775.

Fax Boards? Why Talk About Fax Boards?

Well, although less than half the ports in fax servers sold today are PSTN-connected, OEMs and their channel can’t ignore the 25% of ports that remain PSTN. But that doesn’t mean that enterprises are enthusiastic about investing over $15,000 for a T1 fax board. Not using the MIPS available on ultra-powerful PCs and paying through the nose for DSP-based fax boards hasn’t made sense for 10 years, and buyers are insisting on alternatives if they aren’t quite ready to move to FoIP.

You may recall that BladeWare, which uses the host PC to handle all the fax media processing tasks, has for years supported the Sangoma PSTN-interface boards. As BladeWare supports the entire telephony product line (ISDN PRI, BRI, POTS, etc.) this instantly put BladeWare at the front of the line when it came to PSTN support. And, remember that $15,000 fax board? Well, with BladeWare it’s $3,000, including the per-port software license fee.

But just because PSTN interfaces will go the way of the telegraph sometime in the next decade, we’ve not been resting on past development projects. We’ve invested significantly in BladeWare’s Sangoma support to make it easier for the OEM to develop and support. Moreover, demand for this product line will actually grow significantly when BladeWare’s voice support is released.

So, we’re making sure our OEM customers have the cost-effective PSTN support they need to remain competitive.

Take a look at our PSTN product line on our website.

T.38 Over TCP For BladeWare

T.38 specifies support for both TCP and UDP (UDPTL) as T.38’s transport. Although T.38 over TCP is rarely used, we’ve added it to BladeWare in release 2.4.12 at the request of one of our OEM customers. But why, you ask, is the use of UDP almost universal, after all, TCP is error free, while UDP is best effort? Well, read on…

The long and short answer is latency. TCP was developed specifically for two servers to exchange large data files. Although the faster the file transfer the better, real-time streaming and latency were not top design considerations. However, UDP was designed specifically for low overhead and latency, just what you want in a real-time media transport.

But UDP lacks the features essential for error correction. Enter UDPTL, which adds sequence numbers to the UDP packets, allowing the T.38 application layer to implement forward error correction and redundancy, which are used by the T.38 session if negotiated by SDP.

TCP is so rare that the IETF’s standardization of secure fax in UDP Transport Layer (UDPTL) over Datagram Transport Layer Security (December 2013) is specific to UDPTL. TCP is not mentioned, possibly because TCP has standardized security (TLS) and it’s rarely used.

Want to talk secure fax? Call 770-449-7775, and press 1.

Voice Moves

Yeah, we’re fax guys, but we’ve been developing and licensing voice technologies to OEMs for 20 years. And we even have the industry’s highest-performance VXML interpreter based on VXi, for which we offer a commercial license. And then there’s BladeWare Studio, a suite of products including Studio Client and Studio Server, which gives you a GUI-based application developer and standards-based server to publish your vendor-independent VXML-based apps. But, for most developers, that’s not good enough: where’s the voice platform?

Unless the OEM already has a voice platform, there’s no place for that nice high-performance interpreter to execute. That’s where BladeWare voice comes in. BladeWare is Commetrex’ value-adding telephony platform which currently supports fax for both PSTN and SIP, but it’s readily extensible to include support for additional media and networks, such as voice, video, and WebRTC. But, although we’ve had great G.168 LEC, vocoders, CPA, and tone technologies for OpenMedia, our signal-processing subsystem, for a long time, there’s a lot more to comprehensive voice support. So we’ve been working on it.

Finally, last week we completed a project to take what OpenMedia calls Media-Stream Transforms (MSTs … the “algorithms”) and integrate them into OpenMedia, then we added the other MSTs needed to make our voice feature “comprehensive” for messaging, voice response, and gateway applications. Call it BladeWare voice Phase I.

Phase II requires that we drop this voice subsystem into BladeWare and integrate it with BladeWare’s call-control subsystems. We’ve had it relatively easy until now since supporting voice in SIP is much more complicated than fax. So, stay tuned.

Want to learn more about our voice initiative? Need a voice subsystem for your new server or gateway? We now have it on the shelf. Give us a call or email us today.

Rendezvous In Vegas Or New Orleans?

Commetrex and our sister company, NetGen Communications, will be exhibiting at ITEXPO Vegas in August. We’ve moved up to a bigger booth and will be sharing the space with New Rock Technologies, NetGen’s partner out of Shanghai, China. Please plan to stop by booth 520 and learn more about Smart ATA, NetGen’s soon-to-be-announced wireless IP PBX, and other solutions we offer to make FoIP work for you.

Not going to the show in Vegas? You’ll have another chance to catch us at Cloud Partners in New Orleans in September. This will be our first time exhibiting at this show, but we’re extending our market reach and are very excited about the new opportunity.

We hope to see you at one of these events. In the meantime, visit our website or drop us an email.