Skype’s Heartbeat blog recently posted an explanation of why there was a massive Skype outage affecting millions of customers on Thursday, August 16th carrying through until Friday. Their explanation was that there was a bug in the Skype client software that was made evident by a major Windows Update that culminated in the simultaneous rebooting of machines throughout the globe.

While it seems plausible on the surface, if you look at how Windows Updates actually work, it seems far less so. Even if set at the default time of 3 in the morning for a Windows update and restart, this has some randomisation built in, and it goes by the local system clock.  If EVERYone in the world had his computer set to reboot at 3 in the morning, they still wouldn’t all reboot at once because there’s simply more than one time zone in the world.

They go on to say:

Normally Skype’s peer-to-peer network has an inbuilt ability to self-heal, however, this event revealed a previously unseen software bug within the network resource allocation algorithm which prevented the self-healing function from working quickly. Regrettably, as a result of this disruption, Skype was unavailable to the majority of its users for approximately two days.

Again, this seems a little less than truth. Massive Windows updates have happened hundreds upon hundreds of times since Skype’s inception, and this bug only just now cropped up?

Mathaba News Agency reveals their take on the reason behind the Skype outage, which, while a bit over the top, is at least as plausible as the Skype “we had this bug that suddenly cropped up out of nowhere even though it’s existed on our network for years and years” explanation.

It does seem far more likely that a poorly-tested and rushed software update was likely the cause of this error than simple random chance, but with Skype covering its tracks by blaming other companies, it’s unlikely we’ll ever know the truth behind the outage.

Perhaps if Skype had opened its communications protocol instead of clamping down on it in an effort to squeeze as much money from third-party developers as possible, any actual bugs in the system might have been discovered and fixed years ago instead of cropping up all of a sudden for no stated reason.  This is the hazard of relying upon Skype for stability and security instead of a provider that uses a more open protocol such as SIP.  There’s no way to really know what’s going on behind the scenes.