It’s nearing the end of the year so some of the punditry have started making prognostications. Those who don’t look back at the year just past for fear that the coming year holds untold terrors. And of course, top ten lists start showing up well beyond the confines of David Letterman’s Late Show.
It’s been a while since I paid any attention to OnSIP. Since they are my primary ITSP this very fact is probably “a good thing.” It means that we haven’t had any issues. However, they have been making a few changes in their service. These changes bear closer examination.
Dr. Linden collected a nice stable of facts in making his points regarding the use of G.722. It’s simply old and less than optimal for use over IP networks. It’s not as bandwidth efficient as many of the new codecs, resulting is lower call quality for a given data-rate. He points to a 2007 study of ITU standard wideband codecs that is quite clear that G.722 is back-of-the-pack from a pure performance perspective.
The post is a great collection of information and he is absolutely correct in making all of his points. But I think that there may be more to it than the argument he lays out, strong though it may be.
David Frankel’s ZipDX is the topic of an article over at Telephony Online. VUC regulars have been able to enjoy the benefits of the ZipDX wideband conference bridge for the past couple of months. The company has offered up their conference bridge to users who have the necessary phones to join the call in G.722-based wideband.
Ok, this is going to be a rant. Consider yourselves warned. And worse than that, it’s more or less a repeat of a rant from not long ago. The theme is essentially “Eating Our Own Dog Food” and it harkens back to thoughts of the Emperors New Clothes, or perhaps the state of the mechanics own car.
To what I am I referring? Well, in this case it’s the Squawk Box podcast from Feb 29. The topic was, netbooks vs smart phones and was extremely interesting. However the call, and resulting podcast, was also profoundly aggravating.
As expected the VUC call on Nov 7 about wideband VoIP proved very interesting. It was well attended with a dozen participants on the ZipDX wideband bridge and another twenty on the Talkshoe narrowband conference bridge. Our guest, David Frankel of ZipDX, did a good job of introducing wideband telephony, it’s advantages and some of the issues surrounding its implementation.
We recorded the call in several places so that we have both wideband and narrowband recordings available for comparison after the fact. History has shown that many people download the conference recordings, even many months after the original conference date. It’s evidence of “the long tail” phenomenon that we hear about so often.
However, some people are very visual so I thought I’d bolster the archive recordings by doing some simple visual analysis of the spectral energy distribution in each type of call. Happily, Cool Edit Pro (now Adobe Audition) makes it really simple to generate both waveform and spectral views of an audio clip.