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Google Voice Discovered Allowing Pure VoIP Calls 110

From the article "Google Voice users learned late Monday that the service now has a way of making purely Internet-based phone calls. Making a SIP call with a 'sip:' prefix, the Google Voice phone number and skips the conventional phone network entirely, saving users cellphone minutes. Disruptive Telephony tested it and found that a call worked 'great.'"
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Google Voice Discovered Allowing Pure VoIP Calls

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  • Sniffing? (Score:2, Interesting)

    I'm too lazy to look it up. Do they encrypt the SIP data or can anyone in the middle listen in with WireShark?
    • Re: (Score:1, Funny)

      by Anonymous Coward

      Not encrypted at all.

      Plus Google records all your calls. I wouldn't trust Google for anything. I have no idea why people like Google.

    • Re:Sniffing? (Score:5, Informative)

      by Onuma ( 947856 ) on Tuesday March 08, 2011 @04:44PM (#35423062)
      Unless I'm misreading the chart, it seems like gvoice has SRTP encryption. []
      • Re: (Score:2, Redundant)

        +5 informative to you, sir. Nice work.
      • You are misreading the chart
      • by forand ( 530402 )
        How are you gleaning this from the link provided? The server software which Google Voice may be running, YATE, is not listed on the link you provided.
      • by Anonymous Coward

        SRTP doesn't provide end-to-end encryption - only as far as the SIP server, Google would still be able to decrypt the data.
        It's also useless unless the SIP packets are encrypted with TLS, as the encryption key is sent through the SIP signalling in plaintext.

        If they support ZRTP, that would provide end-to-end encryption.

        But since it's going out to the PSTN, they *are* the other end, so that they can decrypt the voice and sent it over the PSTN. There's no way to avoid that.

    • by suso ( 153703 ) *

      I'm too lazy to look it up. Do they encrypt the SIP data or can anyone in the middle listen in with WireShark?

      You can always speak in Swahili. Oh wait, Google Translate knows Swahili. Damnit!

      • But there are thousands of languages that they don't translate. There are hundreds if not thousands of languages that are not documented either. So, all you have to do is make friends with some aging Native Americans and learn their language! Some native languages of (North and South) America only have a handful of speakers left and are sparsely documented or undocumented and dying out as national languages (English, Spanish, Portuguese) displace them. There are also lots of undocumented languages in remote

  • With the Google Talk Voice and Video plugin, you have been able to make free internet calls for a long time now, and they will even remain free (in the US anyway) for the rest of the year at least. In fact, on the Google Voice page, it has the option of calling from gchat, and I do that now quite frequently as it's easier and better quality than my phone.

    • by Anonymous Coward

      But it looks like now someone can call you OUTSIDE of gmail. Hopefully they'll add sip login so that google voice users can call too and not only receive.

      • by Anonymous Coward

        I don't understand what you mean by this.

        Google Talk is based on XMPP and the service supports jingle (audio/video) and federation (connecting to other XMPP servers). I have been able to do audio and video calls from my account to Google Talk users for quite awhile. If there is also SIP support that is not a bad thing but it's not like audio calls between Google Talk users and users of other servers is something new.

        • You can make phone calls, to peoples' mobile phone, or home landline, using a data-only connection on your mobile phone running Google Voice. And they can call your Google Voice number from their home landline and it rings on your mobile phone thru the data connection. (Mobile phone without a minute plan).
          • by lee1 ( 219161 )
            Really? On what phones? It can not do this on the iPhone.
            • Android 2.3 can make SIP calls over the phone's data connection, right from the built-in phonebook. My old Nokia E61 could do it too.

              • by caspy7 ( 117545 )

                Both of these comments are accurate.
                Data calls cannot be made using the iPhone's Google Voice App, but they can using Android's. The iPhone app forces you to use your carrier's phone network.

    • Now it seems i can hook up a sip client on my phone/ipod and use this. This is major news to me.

    • The awesome thing about this is that I can use an ATA to make a phone call directly from my desk phone without having to use the web interface or having Google call me. Also, I can use the SIP support built into Android 2.3 to make calls via wifi.

      • I currently use as a SIP provider to do just this. It's not free, but at $2.95 a month for a dial-in number, and $0.02 a minute for outbound calls to the US, it's pretty darn close. Call quality is comparable to land line phone calls.

        Is it just because SIP + Google Voice will presumably be free that people are getting so excited?
        • I use Callcentric as well, but I think the reason people are excited is because lots of people use Google Voice (for the follow-me services and voicemail-as-text, mostly), so the userbase is a lot larger than anything Callcentric is likely to have in the near future. And when you are talking about communications technology, "network effects" that depend on having a large number of users are very important.

          But the upshot for people who already have a SIP provider like Callcentric handling their home phone i

    • by cjb658 ( 1235986 )

      I'm confused. The article makes it sound like this lets you call someone else's Google Voice number using any SIP client, but it doesn't help you make or receive calls if you have Google Voice?

      Here is what I'm trying to do. I have an Android phone and Google Voice. I get poor cell phone reception at my house, so I would like to be able to use Wifi on my phone to make, and more importantly, receive calls.

      Does this make that possible?

  • by Anonymous Coward

    This works mint. I saw the Tweet this morning and tried it out and boy does it work. I use Sipdroid in London and top hole!

  • by Anonymous Coward on Tuesday March 08, 2011 @04:41PM (#35423024) now silent. See -->

    • Great. You broke it, Slashdot. Good going.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      So basically Google gTalk is just SIP with some features (not very surprising) and they had an open gateway. Now they closed it.

      What is surprising is why people even care whether gTalk is accessible with SIP or not. SIP is freely available with tons of providers of hardware phones (eg. grandstream) as well as PBX software (eg. Asterisk) as well as termination/origination providers to/from PSTN networks (eg.,, etc. etc. etc.)

      This is only inaccessible if you are behind some retarded NAT

    • by mysidia ( 191772 ) on Tuesday March 08, 2011 @05:02PM (#35423266)

      My (faint) suspicion is some VoIP telespammers/tele fraudsters saw the Slashdot article/blog and immediately started abusing the feature...

      As nice as 'free SIP access' to the POTS network through Google voice might sound, it's not sane.

      Even less sane than having offering open SMTP relays, anyways; since the telephone network is so poorly equipped to deal with any type of abuse (other than it actually being a crime if the perp happens to live in a 'civilized' country, and happens to be traceable).

      • IIRC, you need to verify that you have a mobile (or POTS) number to sign up for a Voice account, so anyone who can get an account already has access to the POTS network.

        Also, if Gizmo5 offered the same access, why wasn't it a problem for them? Or was it?

      • Why would they just start abusing it now rather than when it was introduced on

        • by mysidia ( 191772 )

          Why would they just start abusing it now rather than when it was introduced on

          Higher bar. Brute force SIP dialing against possible google voice phone numbers to spam them is a lot simpler than trying to automate access to a Web GUI that potentially has captchas involved.

      • As nice as 'free SIP access' to the POTS network through Google voice might sound, it's not sane.

        I'd be happy with just inbound access to Google Voice via SIP. I forwarded my cell calls from Asterisk to Google Voice via PTSN - seems right silly.

    • Crap.

      They bought out Gizmo5 a year and half ago, just about the time I was seriously looking at SIP for home use. One day it was there, the next .. nope. I saw this and figured that Google was finally tying Gizmo5 to gVoice. Well, crap. It doesn't seem to be so ... at least not yet.

    • I'm guessing they quickly got some very loud "feedback" from the cellular providers.

  • by morgandelra ( 448341 ) on Tuesday March 08, 2011 @05:00PM (#35423248)

    If you take an android device with google voice installed. Tell it use google voice for all calls. The get an Xlink device ( []). Peer the XLink to your android device via bluetooth. Now you have analog dial tone coming out of the XLink and you can put it into a PBX or regular analog phones.

    • by Anonymous Coward

      Yes, that is definitely just as easy and convenient!

    • by h4rr4r ( 612664 )

      So what was the point of that considering that you have to still have to pay for cellular minutes?

      • ... dirt cheap android tablet + wifi ftw

        just sayin'

        • by h4rr4r ( 612664 )

          I am just pissed that I cannot cancel the voice on my smartphone. I would much rather just use VOIP over wifi and 3G.

          • I don't have that problem. But I am a special case, being that my cell carrier is my employer. I keep 15-20 numbers active on all sorts of phones for testing.

            • by h4rr4r ( 612664 )

              My employer pays for my cell plan, but if I could have data only I would get to pocket about half the stipend.

          • Verizon and T-Mobile allow you to have a data-only plan on your smartphone, something like $50/mo. Not dirt cheap, mind you, but no sense in paying an extra $20 for voice that you're never going to use, right? Dunno about Sprint, though, and it's not an option o AT&T.

      • Re: (Score:2, Informative)

        by Anonymous Coward

        You don't. I cancelled my voice plan with Verizon. I'm at $50 a month right now for my data-only Droid contract.

    • If you take an android device with google voice installed. Tell it use google voice for all calls. The get an Xlink device ( []). Peer the XLink to your android device via bluetooth. Now you have analog dial tone coming out of the XLink and you can put it into a PBX or regular analog phones.

      Dude, the entire point is not needing to have a phone other than the google voice number.

    • You can do this without the Bluetooth peering using a VoIP box [].

    • Or you can by an SIP phone.
  • Would this necessarily mean they'd allow a SIP client to connect and receive incoming calls?

    This move makes sense now that they really killed Gizmo5. In effect, they've finally pushed that feature set to all Google voice numbers.

  • by thanasakis ( 225405 ) on Tuesday March 08, 2011 @05:06PM (#35423304)

    Gizmo5 (acquired by Google) will be shutting down on April 3rd. So no more SIP from them. Does anyone know whether it will become possible to make calls to normal numbers by using a google account? Right now it is possible to make calls from within gmail by adding credit to one's account. What is not possible is to use SIP equipment (many good adsl routers and ATA devices have fxp ports and VoIP SIP functionality) to make these calls. So many of us that were using gizmo5 SIP are left in the cold. Any good gizmo5 alternatives anyone?

    • Try They have an integration with gtalk so you can use gvoice as a trunk without a separate service. If you have an android phone, you can download sipdroid and it will give you the option to automatically set up a pbxes account linked to your gvoice account. You can then point other sip devices to your pbxes account as well. Works great for me.

      • I set up an account there using Sipdroid, the only issue is that when I call my GV number, my phone will ring like normal (due to my real cell number being set as a number to call in the GV settings) AND over SIP, so the phone is ringing 2 things at the same time. Weird. :)

        • by enFi ( 1401137 )
          I tried this (and was very excited to find it), but sipdroid seems to have trouble staying logged in to pbxes, so I only sometimes get incoming calls (or can make outgoing calls); and call quality is ok-to-poor (but it is free).
    • by bryansj ( 89051 ) on Tuesday March 08, 2011 @05:31PM (#35423626)
      I use an Obi110 device to make and receive calls on my home phone using Google Voice. It was the best $50 I've spent on a VoIP solution. It will remain free until at least the end of the year while GV is still free. Before that I used a Linksys PAP2 connected to an Asterisk server to do the same thing.
    • Yes, I've been making real, 100% VOIP calls on my Android device over WiFi with my GV for a while. There's a whole project dedicated to it: []
      Personally, I use the IPKall + Sipsorcery method, but I hear signups at Sipsorcery are currently closed. I'm not sure what's available in the meantime.

    • I switched away from Gizmo5 when I noticed there was high latency on the line and a delay in ringing the IP phone. You could try to use They are a PSTN to SIP broker and provide a telephone number for free. You could forward your Google Voice to this number and calls route normally inbound.
  • Gizmo5 (Score:2, Informative)

    by Anonymous Coward

    After purchasing gizmo5, they destroyed my home phone service. I was not allowed to renew my call in number forcing me to use google voice to rout my incoming calls. At the same time, they took away my year subscription to modify my outgoing caller id with the purchase caller ID option, they refunded me by giving me $4 of call out minutes (dumb asses!). Every time I call out, the call appears to be coming from a number that has now been canceled for about a year, and cannot be modified. Now, about a week ag

    • by Bert64 ( 520050 )

      Not sure about where you are, but some countries have telecoms regulators giving you the legal right to port your telephone service to another provider...
      I would never let myself depend on such a service without having an exit strategy, and being able to take your number and move it to a different provider at will is a pretty good one.

  • by Anonymous Coward

    Phono is a simple jQuery plugin and JavaScript library that turns any web browser into a phone; capable of making phone calls and sending instant messages. You can even connect to SIP clients; all with a simple unified API.

  • You can already make this sort of call via the Gmail interface.

  • by Anonymous Coward

    By emailing me (a up-to-now satisfied Gizmo5 user) about discontinuation of the gizmo5 service less than a month from now, without having a viable SIP-compatible alternative already prepared, I've already made other arrangements that don't involve Google.

  • Isnt this how they already do it?

  • When are we going to get rid of the echos of the 1920's and just treat data as data.

    Then I guess there will be a "data" tax instead of a gazillion weird phone taxes.

  • Now if Google Voice would only let me forward my google voice number to a SIP URI, then I would be in great shape.

    I have been doing this with Gizmo for some time and it worked great, now that its disapearing. I could forward GV to Gizmo and then send Gizmo to a SIP URI that terminated in my hosted Asterisk server and from there I could do basically whatever I wanted.

    I would also like the ability to forward my Google Voice number to an international number, which Google Voice doesn't offer even as a paid service.

    While I'm complaining, It would also be great if I could purchase GV credit and send outbound traffic from my Asterisk or Kamailio to GV via SIP.
  • "Google Voice Discovered Allowing Pure VoIP Calls"

    Can someone translate this abortion of a sentence into English? Slashdot needs to hire some editors.

  • Man would of been nice to point a red 5 server at it.

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