Skype-ifying your voice applications
March 31st, 2008 by Dan YorkToday over on his Tech News Comments blog, Markus Göbel writes about how he uses an application on our Evolution site as a bridge from Skype to the phone network. People who call him on his Skype ID ring him on his desk phone or cell phone. It’s a great little demonstration of our transfer capabilities.
Markus also wonders what I think about this solution, especially given that I had written about Skype’s lack of interoperability on my Disruptive Telephony blog earlier this year. Well, first off, I’m delighted that Markus is experimenting with our platform and we do appreciate his kind words and writing about his experience. We’re glad to see he liked our Designer tool. We’ve put a lot of work into making that an easy and simple way to create voice applications without requiring you to learn all the intricacies of VoiceXML.
Second, he’s right that I’ve known about the “Skype-to-phone” capabilities of our platform and in fact I’ve used it for some of my own applications that I’ve developed on our platform. I just haven’t written about it on any of my blogs for two reasons:
1. The inbound Skype connection is there to allow our developers to build interesting applications for Skype; and
2. The connection is only one-way and doesn’t provide the full interoperability that I was writing about.
Let me hit each of these points separately. First, one of the coolest things to me about developing voice apps on our Evolution hosted platform is how incredibly easy it is have an app that can be reached from a range of different sources. As shown in the diagram to the right, any application you create can be reached through the following methods:
- Direct dial across the PSTN to a direct phone number (and applications can be assigned more than one number – for instance if you wanted numbers in different area codes)
- Dialing across the PSTN to an 800-number with a PIN code.
- Dialing across the PSTN to a non-800-number with a PIN code (which I didn’t show in the diagram)
- Inbound connections from SIP endpoints
- Inbound connections from Skype users
- Inbound connections from FWD (formerly FreeWorldDiallup)
Any of you reading this can try it out – just follow our Quick Start Guide. Skype is one of the ways that you can connect to whatever kind of application you create. As an example, here are the contact numbers for a small application of mine (a call-in comment line for my Blue Box podcast):

Pretty cool stuff, eh? Of the many things you can do with your application, you can of course make outbound transfers to the following services:
- Regular PSTN phone numbers (note that free Evolution developer accounts are restricted to making calls within the USA)
- SIP endpoints (including FWD users)
Note that outbound dialing is not enabled by default but if you email our support team we will issue you a “token” that you can use for outbound calling from your app.
What Markus did was create a very simple app that did an outbound transfer over SIP to a service which then rang his various phones. (As he is in Germany, the free Evolution accounts could presumably not call his number directly. Paid Evolution accounts, can, of course, call anywhere and pay the corresponding rates.) Calls can come in via Skype (or other means) and go out via SIP.
So if this is a “Skype-to-SIP” gateway, why aren’t we trumpeting it to the world? Simple… that’s not the purpose of the Skype connection. The inbound connection from Skype is to allow the 30,000+ developers on Evolution to build interesting apps that can work with Skype. Sure, you can obviously create a simple Skype to SIP “transfer” application like Markus did, but that’s not why Skype created the connection with us and if all we used it for was Skype-to-SIP transfers probably at some point Skype might clamp down on the usage. So while it certainly can be done, we ask people to understand the real reason we have the connection and to please not abuse that.
The second reason I personally haven’t written about this capability is because it’s not a full Skype interoperability solution. If you look on the right side of the diagram above, what’s missing? We can accept inbound connections from Skype (which is admittedly very cool for our apps), but we can’t do outbound connections to Skype users. If you look back at my article about Skype interop what I want is the ability to make SIP connections from within the Skype client itself. In contrast to Markus, who is now delighted that he can turn off his Skype client yet still receive calls to his ID, I want to use the Skype client and be able to call SIP endpoints.
In any event, I’m delighted that Markus is trying out our platform. He concludes his piece with:
Let’s see which other solutions I can develop with Voxeo. Their visual tool makes the design of VoiceXML fairly easy.
I, too, look forward to seeing what other solutions he’ll develop!
Technorati Tags: skype, sip, voxeo, applications, xml, voicexml, fwd
Related posts:
- Congrats to Skype on their new independence!
- Happy 5th Birthday, Skype!
- Launching your own *platform* for voice applications using Voxeo’s computing cloud
- What types of applications do people create with Voxeo platforms?
- Making voice verification / voice biometrics EASY, for a change…
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April 2nd, 2008 at 4:46 am
Hello Dan,
thank you for this post. I’m just a journalist, but a quite techie one. After having played with Evolution for one night I understood the rules and now I am looking forward to leverage them.
Your figures about the inbound and outbound possibilities of the Evolution platform are very impressing and as a constant VoIP tinkerer I am already thinking what to do with them. Maybe few of my blog readers will try to sign up now, but I guess only the ones who really are developers.
Best regards, Markus Göbel
April 3rd, 2008 at 2:37 pm
Markus,
Well, thank *you* for writing about our platform in your blog. I’m glad you found the possibilities of our Evolution platform impressive and I look forward to seeing what you may come up with next!
Thanks, Dan
April 15th, 2008 at 4:05 pm
[...] myself and the answer is something you can test yourself by calling one of these numbers (since we support all these forms of [...]
April 29th, 2008 at 5:14 pm
[...] realtà, come segnalato sul blog dello sviluppatore, la piattaforma Evolution non fornisce una vera e propria interoperabilità completa: infatti è [...]
May 23rd, 2008 at 7:40 am
[...] “cloud” is then connected out into other “clouds”. You can connect to our cloud from the PSTN, SIP or Skype and then go back out to the PSTN or SIP clouds. We’re part of the massive interconnect [...]
May 29th, 2008 at 3:50 am
[...] “cloud” is then connected out into other “clouds”. You can connect to our cloud from the PSTN, SIP or Skype and then go back out to the PSTN or SIP clouds. We’re part of the massive interconnect [...]
August 29th, 2008 at 1:52 pm
[...] fact, I wrote about how to “Skype-ify” your voice applications back in March and any application you develop through our hosted Evolution developer portal [...]
November 2nd, 2008 at 2:41 pm
[...] Voxeo’s hosted "cloud" also supports connectivity to Skype for inbound [...]
January 23rd, 2009 at 4:55 pm
[...] PHONE NUMBER – You now have a choice. If you just want to test your voice app calling in via Skype (read more about calling into your apps using Skype), SIP, or using an 800-number and a PIN, you’re done. Just click “Create [...]
March 24th, 2009 at 9:32 pm
[...] what we’ve had for about four years now in our hosted application platform (and about which I wrote about last year). According to the info from Skype, Skype users would be able to call into applications by calling [...]
March 27th, 2009 at 6:27 pm
Is this still available?
Now the Call Routing tab says:
100% of your call traffic is routed to the Voxeo hosted network. You don’t have any call routing options because there aren’t any Prophecy servers registered to your account.
Thanks
March 27th, 2009 at 8:55 pm
Yes, if you click on the “Phone Numbers” tab for your application you will see a number for “Skype VoIP” listed in the table. It has the form
+99000936 9991427651
which you can just enter into Skype and call. Hope that helps.
May 12th, 2009 at 1:59 pm
[...] We still are huge fans of Skype, use it heavily internally and are very pleased that we are able to provide inbound Skype connections to voice applications on our platform. We want Skype to [...]
November 23rd, 2009 at 4:57 pm
[...] a partner of theirs since back in 2005. As I’ve noted in previous blog posts, notably “Skype-ifying your voice applications“, we automatically provide an inbound Skype number to call any XML application you create on [...]