What Gives with V.34 Fax?

Currently, there are not many V.34-capable gateways available, and only one V.34-capable FoIP fax server. This is so despite the fact that over half of the machines installed in the last five years support V.34. So, what gives?

Well, for one thing (and trust us when we say this) it’s difficult to implement. It’s still heavily encumbered with patents. And another is that, compared with V.17, it’s a resource hog, both MIPS and RAM, which can give an embedded-system designer pause. Then, there’s the added complexity of handling V.34 in SIP signaling. Lots of moving parts.

But we’ve stolen a march on our competitors and now done it all. BladeWare is shipping with T.38 version 3 with V.34, G.711 pass-through IP fax with V.34, and V.34 in PSTN applications on all of the Sangoma telephony boards. But with some HMP servers only supporting 60 or 120 ports of T.38, which is easy on the MIPS, what kind of capacity can you get with V.34 on an HMP system? Well, the answer is plenty with BladeWare.

Over the years we’ve been able to do a pretty good job of optimizing our ANSI-C-coded fax modems, so our V.34 got off to a good start. Then, Moore’s law and multi-core processors to the rescue! It turns out that our modems just love multi-core architectures. Both Linux and Windows do a fine job of putting the modems on one core, where they appear to fit into cache and just rip. The other core in a dual-core machine takes care of the application and file I/O, which is an important aspect of any fax application.

You want performance? Well, how about this! On a dual-core 3-GHz PC we can run 60 V.34 transmits sending to 60 V.34 receive channels and only use 30% of the computer’s MIPS. And, with the Sangoma digital boards supporting up to 8 spans in one PCI or PCI Express slot, who needs expensive fax boards.

So, if you’re looking for V.34, you know where to get it!

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