The Skype outage in the week just before Christmas was an inconvenience to millions of people who use the internet phone service.

For up to two days, the service was effectively unavailable to tens of millions of people  – no voice or video calling, no text messaging.

I remember the last time Skype suffered a major service interruption like this, in 2007. That event was characterized by poor communication to users and the world at large as to what was happening and what Skype was doing to get its service back up and running.

In 2007, there were about 7 million people using Skype at an average time. Today that number has grown to about 22 million (that’s the number I recall seeing on my Skype app just before last week’s outage hit). And this time, communication certainly was much better with service status update posts and, significantly, video blog posts by Skype’s current CEO, Tony Bates (whose concise bio, incidentally, says "I’m responsible for overseeing the company’s direction and strategy and am ultimately responsible for its performance.").

Timely and effective communication is key at times like this especially in today’s world where your every action (and inaction) comes under close scrutiny and intense public commentary on Twitter and other online places.

Overall, I think Skype did a good job in communicating what was going on as evidenced by the blog posts and Twitter handle. Can’t say the same for Skype’s status update site, though – even today, the site gives the impression that the outage isn’t resolved with the last announcement posted on December 22.

Still, it’s all a great improvement over 2007, enhanced by Tony Bates’ gesture of offering customers a voucher for 30 minutes of free talk time for calling landline numbers from  your Skype account.

In money terms, it’s a one-dollar value per voucher. Not a lot, you might think (although if Skype offers it to everyone online at the time of the outage, that’s potentially a $22 million overall value), but I think it’s the gesture that is the real value.

Is it enough, though? Will it reassure users that Skype is reliable enough to be their primary telephony service? What about the cause of the outage? According to a post by Skype CIO Lars Rabbe a few days ago, it was a ‘perfect storm’ situation involving a specific version of the Skype program for Windows, support servers and supernodes, the peer-to-peer network hubs that enable much of Skype’s functionality (for a detailed explanation of supernodes, see Dan York’s excellent post).

While many individuals and small businesses will move along and continue using Skype (I’m one of those individuals), I think the real issue of concern for Skype is long term. Would you be willing to give up your traditional phone system for Skype? I wouldn’t, not yet – it’s not reliable enough as this major outage confirms. (And, incidentally, that’s a situation facing every internet telephony service: it’s not only Skype)

For large businesses, the situation is probably worse for Skype (especially when planning an IPO). They want things like service-level agreements, really difficult to do for a distributed service (ie, P2P) where there is no central control.

I’ve been a Skype user since 2004 and will continue to use it. But I’m not planning on giving up my alternative phones – mobile – just yet.

“Granny, did the supernodes just crash again?”:

[…] To prove that Skype can finally turn its massive user base into a large and profitable business, [CEO Tony Bates] needs to convince business users to adopt the service in far larger numbers. Indeed, from what we’ve heard from one person close to the situation, a large part of the reason for pursuing an IPO in the first place is to set Skype apart from the growing mass of VOIP competitors in the eyes of business customers.

To the extent that it hints at possible flaws in the architecture of the system, last week’s crash will not make Mr Bates’ job any easier.