Comments on: Skype For SIP: Sorting Through the Issues

By: Skype’s Stefan Öberg @ Interop: Stealthing Skype Into Business, But Cover the Entire Skype Ecosystem | Voice on the Web

Mon, 29 Jun 2009 11:33:23 +0000

[...] Skype For SIP: Sorting Through the Issues (voiceontheweb.biz) [...]

By: Robert Wolpov

Robert Wolpov — Mon, 30 Mar 2009 01:08:07 +0000

I am waiting to hear more information about the "multiple Skype id to one SIP identity" concept. Does this mean that you will not be able to map SIP addresses to Skype ID's? We have been waiting for this for a long time. It only makes sense that ultimately, you would be able to map any SIP address to a Skype ID. Our service, OnSIP is built on SIP addresses. Every user, application, phone number, auto-attendant, voice mailbox, etc. has a sip address that is private to each business' personal domain. We would love to help our users be reached by and reach unique Skype IDs.

By: rmclaren

rmclaren — Sun, 29 Mar 2009 01:47:11 +0000

It will be interesting to see if there is an increase in the business uptake of Skype. I have not been able to interest my company of around 2000 employees and 100 offices in VOIP/Skype. Their attitude is that they can always squeeze AT&T for better rates that make the cost of moving to VOIP/Skype unrealistic. Perhaps smaller/newer companies with less invested in legacy landlines will be more interested.

I also wonder if SIP-to-Skype is that important. Typically, if I am at a SIP phone, I don’t know if the called party is available on Skype. (This differs from Skype, where the presence information is available in the Skype client.) If I am trying to get hold of a family member, my first attempt is likely to be a call to the landline. (I’m talking here about calls to countries with “caller pay” in terms of cellular.) Calls to a landline in many countries are free; I use Betamax and have been calling the UK for free for years. If unavailable, my next call is to the cellular number; again, for example, calling a UK mobile number is around 7 or 8 cents per minute on Betamax. If I don’t get through, I’ll leave a message as I did today when calling my brother. He returned the call while hill walking after climbing half way up a Scottish mountain to get a signal from O2! The point being, I am unlikely to be using Skype to get in touch with someone when using SIP devices.

I believe where the Skype/SIP connection comes into its own is to make sure that if someone is using Skype, he/she can get through to me by having access to a Skype-to-SIP interface. I am using Tropo and MySIPSwitch for this at the moment, but OpenSky or a box running SIPtoSIS would work. If I get a call from a Skype user, my first question is likely to be: “Can I call you back?”, at no or little cost. So Skype becomes no more than a call initiation protocol, with the actual communication be carried out by VOIP to PSTN or mobile.

By: Jason

Jason — Tue, 24 Mar 2009 15:02:32 +0000

I am digesting your point in the post on the different business channels for SFS vs SFA. But in reality, many of those that were benefiting from SFA may now use SFS in much the same way. Look at Voxeo, they have happily had the equivalent of SFS for a while and provided some interesting apps in Skype-land. Of course, SIP -> Skype User is a good thing for all, but is involved in a reduced set of use cases.

You may reduce the number of SFA channels you need, as you only need it for Presence and Asterisk -> Skype User calls. As SFS may now handle inbound and SkypeOut calling.

It would not take much for Skype to add the additional user data available over SFA as custom SIP Headers and deliver those over SFS negating that SFA differentiation. Further, I suspect, through Skype’s public silence on the subject, that SFA channels will be limited for a single account to combat the same issues that keep SFS from doing SIP -> Skype Users.