13 Comments

Summary:

GoogleFi, Google’s Mountain View network, may be good for data connections, but is it good enough for making voice calls? In order to find out answers, I headed down to Mountain View to conduct some first hand tests, and well, make some VoIP calls. Voice over […]

GoogleFi, Google’s Mountain View network, may be good for data connections, but is it good enough for making voice calls? In order to find out answers, I headed down to Mountain View to conduct some first hand tests, and well, make some VoIP calls.

Voice over WiFi has the potential to be one of the most disruptive applications for city-wide WiFi networks, unlocking callers from expensive cellular networks. But MuniFi and even WiFi hotspots, many (including Om) argue is not yet reliable when it comes to making phone calls and the devices are still quite complex.

So during another hot daytrip to sunny Mountain View, we took our handhelds and laptops in tow, and spread out our gear under a tree in a city park. First we just tested basic Skype running over a Mac laptop.

The biggest issue is just sitting in a spot with a fast enough connection to the closest access point. After a few tries, we were able to connect and make a regular Skype call to another Skype user online, and managed to get pretty decent voice quality. It’s not as easy or clean as cellular, but it works well enough and it is free!

Test one out of the way, it was time to stress test the network using non-PC devices. We fired up the Nokia 770 Internet Tablet running the Gizmo Project application, which can connect VoIP calls to regular phone numbers. It costs a few cents to make outgoing calls, but we could call anyone over the public phone system and its still pretty cheap.

One problem we noticed with the service is there was a slight lag time between when I called and the listener got the signal. The lag time was large enough to be noticeable. Despite that the call quality was quite clear. Our Pocket PC phones did not play nice with the network, but that might be some configuration issues on our end.

So what is our conclusion? If your call is critical and you’re in a big hurry, and not willing to tinker with new technology, stick to your cellular handset.

Now, if you’re willing to give up the ease-of-use of your mobile handset, then, Google’s Mountain View network is not bad. If you find a spot where the signal is pretty strong, the calls can be as good as cellular calls. It might be just me, but the prospect of cheap or free phone calls over a free network, is something to get excited about.

  1. You’ll really use it only if you have an easy-to-use dual mode device.

    Share
  2. The Nokia 770 can connect automatically to a preconfigured network, so if I could connect a Bluetooth headset to it (still haven’t done that) then making a call over WiFi would be pretty similar to using a mobile phone.
    I’m in Thailand and the quality of the call from Gizmo (to a thai landline) wasn’t quite up to the mobile phone quality, but that seemed to be mainly due to the low volume on the microphone, I was able to hear the other party much better than they could hear me.

    Share
  3. This market is ripe for an iPod like device that takes the task that took you God knows how many hours to complete (find network, fiddle with configs, run dedicated software) and complete them in an instant. A device that would always (try to) be online and able to send and recieve calls instantly. Maybe even we could send small files and text messages.

    We could call it a portable communicator, or even, um, a mobile phone.

    Share
  4. I can’t wait to have access to Google’s Wifi network, but in the meantime I have a Verizon EVDO card, and there is nothing better than being able to parade around town knowing you are fully connected. I think it might be prohibited in the terms of use to make voip calls on the EVDO network, but I “know” someone who has, and the call quality is excelent.

    Share
  5. Paul: Part of the hassle is that Google Wifi runs the same kind of browser-interdiction process that most wifi systems do – you have to log in before you actually have connectivity.

    Now that this is becoming so common, maybe someone needs to come up with an API so that it can be automated. Perhaps an appropriate hidden field in the redirected page, and an appropriate standard for local storage of user credentials. Users should never haev to see these pages. Same problem with FON.com access points, T-mobile, etc. (And, this is why I think we’ll mostly see the first round of VoIP-over-Wifi handsets having some sort of browsers)

    Share
  6. Hi. I have been using VoIP extensively since 1996 (impersonating old man.. I was designing VoIP based business phone systems back when you kids were still in diapers). In fact, I did one test of VoIP over Ricochet nearly ten years ago. It worked, sort of.

    Technically VoIP over ____ works fine if you have 60-100kbps of bandwidth, less if you’re using low bitrate codecs like GSM or G729.

    The main issue is not the transport layer, but the handsets and their (in)ability to switch easily between different modes. Of course the cellular handset vendors will be pressured heavily by carriers not to make this too easy.

    Another point, an innovative mobile operator (they do exist) could make wireless VoIP moot by enabling conventional cellular users to dial VoIP numbers like any other number. If I could call from T-Mobile to someone’s Skype or Gizmo number (cellular to T-Mobile, voip from T-Mobile to ___), that’d be extra convenient, require no special handset s/w, and probably worth a few cents to avoid the hassle of fighting with Windows Mobile.

    Something people often overlook about cellular is that people are happy to pay a premium for ubiquitous, and generally reliable, coverage.

    Share
  7. Actually, it looks like T-mobile is about to launch just such a product. Buy the right handset, and have or buy a supported Wifi AP, then get better coverage at home, and, presumably, when in the warming glow of Wifi provided by an T-mobile partner.

    You missed something important to VoIP, that’s not strictly required for most other apps: reliable, preferably low, latency. If your latency is highly variable (typical, for instance, with many of the 3G network layers, apparently because voice packets get priority over data ones), then it’s much harder to get a good MOS score.

    Share
  8. I’ve got a Dell Axim X51v (Windows Mobile 5.0) with built-in WiFi and Bluetooth. I paired it with my bluetooth headset which I usually use with my cellphone and installed Skype on the Axim. I can now make Skype calls to any phone in the US for free and the quality is great. People I’m speaking with don’t even know I’m not on a regular cell phone. Since I’m using my regular headset, I even forget it’s a VOIP call sometimes. The only problem is the funky caller ID that Skype sends out for SkypeOut calls. With a reliable WiFi connection, I think we’re there today! I do this at home regularly since I no longer have a landline. When I know I’m going to make a long call, it’s nice to save my cell minutes for other uses.

    Share
  9. Jesse Kopelman Thursday, August 3, 2006

    TM how’s your batter life using Skype on the Axim? I found it pathetic on my Windows Mobile device. 3 hour talk time with CDMA, 20 minutes with Skype over WiFi.

    Share
  10. A major contributor affecting voice quality in a Voice Over IP System is inter packet jitter. Inter packet jitter is the difference in time of packets arriving into a CODEC’s buffer.

    As jitter increases, packet loss can occur creating noticeable voice QoS issues.

    The issue with WiFi is an inability to control QoS as it relates to the Media Access Control (MAC) layer – in WiFi it’s the radio interface. There is a specification that provides for better MAC control allowing for consistent QoS for voice called 802.11 D.

    I’m interested in hearing more about your testing, at different times of the day , varying areas that may be congested and if the access points are using 802.11 D.

    Share
  11. I don’t have any networks in my usual locations that require more than a WPA key, but i take the point. Having a username/password login to the network is so outdated though, I don’t see why anyone implements it that way, except that it’s easiest and requires no client software. I also have to admit that i planned one network back in 2001 with exactly that approach.
    On the point about QoS, the only quality that matters is ‘good enough’. I find it funny to hear people refer to mobile and reliability in the same breath – but mobile quality/reliabilty is definitely good enough to make it useful!
    /Paul (written on my Nokia 770 over public wifi)

    Share
  12. 802.11e is actually the specification that has Qos implementation. The lack of QoS support in devices makes it a challenge for VoWifi. So even if there are devices that support 802.11e, you have to have wireless cards that support this standard. The technology is not just there yet.

    However, some devices in the market allow users to change settings that can help prioritize voice. Like the Linksys WRT54GL; this device can be upgraded with a dd-rt or other firmware that allows users to change settings that can GREATLY impact the voice quality. I did some test with this device and the change in quality was quite noticeable.

    I think one of the major applications that will be useful for VoWifi initially is group-based Push to Talk (PTT) over Wifi using VoIP technologies. Since there is no need for a consistent stream, delays might be acceptable in some cases.

    Share
  13. VoIP on WiFi…

    Interesting to see how the market is moving towards convergence applying Voice Over IP to new network models.
    The folks at GigaOm have recently tested VoIP on the GoogleFi Mountain View network.
    Their preliminary testing yielded good results, however…

    Share

Comments have been disabled for this post