You Don't Know Jack about VoIP

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You Don't Know Jack about VoIP

Posted by michael on Tuesday September 21, 2004 @06:05AM from the single-purpose-phone-lines-so-old-skool dept.

gManZboy writes "Phil Sherburne and Cary Fitzgerald, two senior technologists over at Cisco, have written an in-depth overview of VoIP for developers and the like (not for everyone who's ever used a phone). Like Queue's earlier You Don't Know Jack about Disks, this article covers the history, the basic technologies, how they work, and where they're headed. If you found the blog post yesterday lacking, check this one out."

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Re:wheres the link:"you don't know jack about disk by grub · 2004-09-21 06:10 · Score: 5, Informative

here you go

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Trolling is a art,
Test your connection... by fiji · 2004-09-21 06:13 · Score: 5, Informative

Before you waste time trying to get VoIP (or paying for VoIP from a provider) going it is worth testing your connection to see if it can support VoIP calls at a reasonable quality. You might want to test your line at various times during the day... I get crappier calls in the evening.

Anyway, http://testyourvoip.com/ provides a decent free testing serice just using a web browser.

-ben
Which service is better? by exhilaration · 2004-09-21 06:16 · Score: 4, Informative

If you're in the market for a VOIP service, Geekbooks did a pretty decent comparison of different services. Does anyone have any other links?
Re:What we want from Pa Cisco by jaymzter · 2004-09-21 06:23 · Score: 4, Informative

Your comment sounds pretty interesting, since you seem to know what you want, but apparently haven't looked anywhere other than Cisco.

Avaya's IP telephony products provide your encryption, Cell+Wifi with auto switch over, and my favorite, all the servers run GNU/Linux! No video phones yet.

I hear they're really expensive, but I really don't have any clue as to that, I just fix the stuff.

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If thou see a fair woman pay court to her, for thus thou wilt obtain love
Re:VoIP = fad by Ugodown · 2004-09-21 06:24 · Score: 4, Informative

Yeah, Primus VIOP is only $20 /m when whith Telus it's at leas $30 /m for basic service. Plus you can have a extra line for $4 extra that you can place anywhere in Canada. So even though I live in Edmonton I could have a local number in Toronto that I could make local calls to there from. Also people could call me on that line locally and it would ring here in E-town.

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--- to swing on the spiral...
Re:What we want from Pa Cisco by chipperdog · 2004-09-21 07:35 · Score: 3, Informative

>Server software that runs on Linux for those of us that like a standard back office.
like asterisk
It supports many VoIP standards, pots, BRI, PRI, etc...
BANDWIDTH is not free by vpreHoose · 2004-09-21 07:45 · Score: 3, Informative

Where every Cisco VoIP system falls down is on the ammount of bandwidth required to support VoIP. From a telco operator perspective (voice or data) your greatest operational expendature is your bandwidth. Using IP or SIP costs you far more in bandwidth than is economic (when compared to alternatives). Yes you can multiplex voice and data but that takes even more bandwidth than doing it seperately! GSM is probably the most efficient way to carry voice over a digital channel. Does very well at 22kbit/sec. You even can do voice over GPRS at 33kbit/sec (the latency sucks, but you can do it). But try running a SIP session and it simply doesn't work. The protocol to establish the session and the overhead cannot be done on a low bandwidth channel. VoIP makes sence only when bandwith is free, but in the real world it isn't and the commercial imperative is to make the most of it.