Monthly Archives: May 2009

Mythbusting HD Voice: Frequency Response vs Data Rate

snom_820_links_hoch_perspektive_200pxOne common misconception that keeps coming up is the assertion that the higher quality audio available through the use of wideband telephony (aka HDVoice) requires more bandwidth on the network. This is simply not true.

The terminology gets confusing for some folks. On the one hand we’re talking about frequency response of the audio channel being much greater, 50 Hz to >7 KHz for most wideband codecs, as compared to 300 Hz to 3.4KHz for the reference standard G.711. All that extra information has to go somewhere, right?

Read More

Magic Jack: Secrets Of Success?

magicjackusbwidgetSome time ago in a informal VUC post-call session Karl Fife brought up Magic Jack as a topic of discussion. He felt at the time that they were very possibly doomed to failure by their business model. I doubt that this is the case, and laid forth the logic of my belief. Well, earlier a recent thread over at BroadbandReports.com hinted at support for my theory.

It helps to start out understanding Magic Jack and their business model. Simply put, you pay $40 in the first year to establish an account and get the Magic Jack device. Thereafter you can make calls over your broadband by plugging a traditional phone into the MJ dongle, and the dongle into your PC.

Read More

HDVoice Summit: A Beginning

polycom_ip650_256This past week I had the pleasure of attending The HD Communication Summit hosted by Jeff Pulver in New York City. The summit was a one day event intended to rally a number of players in the telecom world around moving beyond the PSTN with the rollout of wideband telephony services.

The event was the first of its kind, and drew a group of over 100 attendees most of whom were telecom industry insiders. For me it was exciting and enlightening to be in the presence of such a group of knowledgeable people.

The day was marked by a number of presentations from various parties and a handful of panels. There’s simply too much to convey in a single post so I’ll start with some of my more general impressions of the issues discussed.

Read More

Choosing A Router/Firewall For A Small Office

net4801_2_lOne project that I’m am about to start is moving from my m0n0wall router to a new one build around pfsense. The motivation for the project is the integration of our Comcast Business Class internet service into the rest of the household. At present there are two separate networks, with only a few devices enjoying the high speed cable service. The pfsense system will be configured for dual WAN, accessing both the cable service and Covad DSL circuit.

My existing m0n0wall runs on an old Soekris Net4801. In service for many years, it has been extremely reliable. If m0n0wall does what you need I have no hesitation in recommending the software. Support from the user community is tremendous as well.

Read More

PhonerLite: Codec vs Sample Rate

In the post-roll after last weeks VUC call with Michael Iedema of Askozia Project I took a little time to join the call using the PhonerLite soft phone. I didn’t tell people right away, but some later commented that I sounded like I was back to narrowband (G.711) During the formal portion of the call I was on the bridge using Eyebeam in wideband (G.722)

Read More

Open Source Hardware Where Art Thou?

audiocodes-mediapack-114VoIP Supply’s Garrett Smith has an interesting post the other day. Actually, we can cross reference a couple of posts to follow his line of thinking. Firstly, he offers some advice on selecting an analog gateway in a post titled, “Four Keys To A Successful Voip Gateway Purchase.” It’s a good basic overview on VoIP gateways for the beginner.

I’ve made my thoughts on gateway/ATA devices well known in the past (here, here and here). I see them as relics of a prior era of VoIP, and to be avoided if at all possible. However, some people feel that they are truly necessary. Whatever floats your boat.

A little later on over at VoIP Supply’s VoIP Insider Blog Garrett poses the question, “Where Are The Open Source VoIP Gateways?” That is a fine question and one the deserves an answer. It also needs to be broken down a bit to get to a clear answer.

Read More
Back To Top
%d bloggers like this: