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Free Software Voice Over IP Solutions?
Shisha asks: "I'm looking for some Voice over IP solution for Unix (Linux, and Solaris in particular). I want to call friends in Prague from the UK. Is there any way how to make the phone call go over the net?" I know there are programs like CCFAudio, Ethernet Phone, FreeWebFone and Speak Freely, however I haven't used any of these programs so I can't say to how well they perform. Have any readers out there tried any of these or have other VoIP solutions that they use that deserve mention?
Caller gets on computer,
which is (or gets on) internet via local 'phone/DSL/cable/intranet-gateway/etc.,
caller starts GnuPhonella, enters international phone number
GnuPhonella locates a DestinationCityLocalArea GnuPhonella node that isn't busy, and negotiates service,
Destination node dials *OUT* into DestinationCityLocalArea,
where someone asnwers by *ORDINARY* phone, and
conversation ensues. (FAX could be done similarly).
Does this exist (I mean for cheap h/w with GPL s/w)? Note that it requires simultaneous internet connection and POTS voice dialout at the destination, to get to an ordinary phone in that area, but with non-phone internet connections becoming common (especially in businesses) that should be less and less of an obstacle.
What cards can dial voice connections for your computer? Any voice modem? Or is there more to it? Special wire to audio card from modem like CD wire? Can you have both?
GnuPhonella nodes could be identified first by their international phone prefix paths, so knowing the number you want to dial could do an automatic search for the a node at that area.
BTW, what would be the legal difference between a group doing this as (a) internal between branches of a business, (b) internal to a human family, (c) a private club, (d) an informal group of friends, or (e) an anonymous public association?
i was implementing a VoIP solution for a company a few weeks ago where linux based kiosk terminals where euquiped with phones that should be able to make VoIP calls to a central callcenter including video. i looked at the existing software. H323 seems to be the way of the futurere and there are already H323 based solutions on the way. openh323.org. even thought they where not stable enought for my needs yet. but at least the demo appication (voxialla) was able to interoperate with the M$ netmeeting shit. video transmition with H263 codec (for low bandwith) is also on the way. for my solution i decided to use quicknet telephony cards (it greatly enhances the telphony experience if you have a real phone connected to your computer which can also ring and is independent of the sound card). those have a DSP on board which does voice compression accourding to the most important standads. it has a GPL'ed kernel driver. (the only downside is the DSP code itself is not open but that is not that much of a problem).
i decided to just adopt the demo code that came with the quicknet cards for my appolication since it was more stable then the H323 things. (it is easy since the compression is already done on the card). for the video thing i used a parallel netscape server push with 1 picture every 3 or 4 sekunds 160x120 (about 2k Byte) in size). greetings mond.
Nautilus is a free(and open-source) voice over IP(or serial connection) program that focuses on encryption, however you can turn it off if you don't want it, or if you run into truble with export laws. I have ran it many times with it's 2.4Kbit codec, and it sounds much better that anything else I have ever heard over 56k modems. Since your only using 2.4kbit/s, if you are using it over bad links, it can easily resend data and have plenty of bandwith still left over.
It will run under DOS,Windows,and many types of Unix
Get it hereLinuxTelephony
openphone.org
Packetizer.com
SpeakFreely.org
Voxilla.org
___
Windows For Telepaths
You open the box labeled "Windows TP", carefully extracting the pouch labeled "License Agreement". You examine the contents of the pouch, finding an inflatable beanie bearing the Windows logo rather than the familiar 3.5" diskette package. You inflate the beanie, insert two "C"-size batteries (not included), and carefully place it on your head. You press the Start button.
Immediately, the image of an hourglass comes to your mind. You find yourself trapped; unable to move anything in your body save your eyes. After an indeterminable delay, you regain control of your senses. You are suddenly compelled to speak your name and business affiliation. You then retrieve your Windows TP package and chant the Product-ID number.
Suddenly you see the words "Windows is detecting new hardware" flash before your eyes. You crash to the floor, writhing in agony. You feel every muscle in your body contract and retract in turn. Your mind is filled with the image of a blue inchworm, creeping slowly across a grey field. The creature finally reaches the edge of its domain, and your seizure ceases. You take a moment to regain your composure, and you are reminded of your high school anatomy course as a complete listing of every organ in your body appears before your eyes. You browse the list for a moment, and utter the phrase "OK". After a short delay, you hear the sound of a trumpet echo through the recesses of your mind.
You find yourself in a large, barren space. You look around, and discover images labeled "My Brain", "Recycle Bin, and "Set up the Microsoft Network". You feel compelled to utter the word "Start", after which a list of options floods your mind. Weary from the detection phase, you utter the word "Shut down". You close your eyes, and blackness surrounds you. You feel yourself start to drift into sleep. Your peace is interrupted, however, as a bright orange light invades your nothingness. "It's now safe to shut down your mind".
You drift into unconsciousness, and sleep for several hours. When you awaken, you are frozen in place as you see clouds and blue cycling colors. After a short eternity, the familiar "My Brain" icon reappears in your mind. But something is terribly wrong; you can feel it in your gut. Just outside the range of primary vision, you can sense something lurking about you on all four sides.
You slowly look up, and see the word "Safe Mode" glaring back at you. You back away slowly, swivel your head, and there it is, behind you as well. Your heartbeat quickened and you are terrified as you turn to your left and your right and it meets you there as well, its cold, heartless glare filling your soul with despair.
Quickly, you summon Control Panel, System, Device Manager. You feel yourself frantically gasping for air as you run through the list of installed devices. You come upon "Respiratory System" and are horrified to see a black exclamation point on a yellow field next to the entry "Lungs". You close your eyes and utter the word "Properties". On the closed curtains of your eyelids, you see your life flashing before your eyes.
You force yourself to concentrate on your situation, attempting to discover which system devices are in conflict, when suddenly your entire body seizes up in pain. You lose all sense of reality. You are floating through the clouds as you hear a voice echo through your mind: "This program has performed an illegal operation and will be terminated." You start to black out and suddenly you remember your situation. You stare in horror at your blue extremities, knowing that, without oxygen, you will not last much longer. With all the consciousness you can muster, you force yourself... To reboot.
You awaken in a place that is dark, but familiar. A solitary white prompt on a black field greets you. You look behind you and see the wreckage of the operating system that nearly spelled your demise. "Cannot find a file that may be needed to run Windows". You turn around to face the prompt, and a wide grin comes across your face. You take a deep breath and revel in the life-giving atmosphere. You laugh as you utter the words, "DELTREE WINDOWS".
Suddenly you find yourself on the floor of your home. You find the charred remains of the Windows TP beanie littering the floor. You carefully gather them up, stack them neatly on an altar, and burn them, promising yourself never to risk your life with Microsoft again. You bury the ashes, knowing that your life is again in order.
crap generating idiot
Get & try RAT: Robust Audio Tool at http://www-mice.cs.ucl.ac.uk/multimedia/software/r at/ It's open source, and they have builds for major platforms (FreeBSD, HP-UX, IRIX, Linux, NetBSD, Solaris, SunOS, and Windows 95/NT). Au regards, Fh
There are some problems with the H323 specification in general though. For example:
There are of course many options in the VoIP world right now - SIP is a protocol that works to simplify the processes of the H323 stack. As far as I know, there are a few different implementations of SIP and none of them work very well with each other. You can read more about it here.
A friend of mine has written some very good articles about Linux and Internet Telephony:
Linux Journal Article
SVLUG Presentation
I personally think that the best solution right now in terms of interoperability, quality and Free-as-in-speech-ness is OpenH323 with OpenPhone. Our company uses a combination of Quicknet PhoneJACKs, OpenH323, and a few CIPE VPN tunnels to connect people from CA to Texas to Australia at their Linux boxes using real-live ringing phones - at essentially no cost. Quality is very very close to a typical old-guard phone call, even from San Francisco to Sydney over the Internet, _and_ encrypted. Blows my mind whenever I use this stuff. The Quicknet cards have GPL'd drivers and are in the current kernel tree. They seem to add a ton of power to the call by offloading alot of the work to hardware DSPs.
SIP is the IETF standard for signalling of VoIP calls (as well as other multimedia conferences). It is supported in products by 3Com, Nortel, Cisco, ... Very cool.
You can check it out in the kdenonbeta package of KDE 2.0.