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Understanding Today's Skype Outage: Explaining Supernodes

disruptivetelephony.com

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Re: Understanding Today's Skype Outage: Explaining Supernodes

#11

Post by raamdev »

rix0r wrote: post #9
drats wrote: post #5

My theory: Tons of supernodes (static ip with no NAT, broadband, constantly on) are in the 20s-30s age group and are on holiday. Plus office and university machines that are normally left on have been turned off. The people I know in universities across Europe normally have skype on at work constantly, or at least during the day, and most have static ips on their uni networks so I imagine they get selected as superno…

That could very well be the case, but if that were really the cause you'd expect to see this pattern every year. However, it apparently didn't happen for at least two years in a row[1]. Also, I would have expected Skype engineers to have wised up to the situation by now if it were really a seasonal thing. [1] Since the last outage was 3 years ago. I can't find a source for that right now -- would be interesting to se…

It could be that growth in Skype usage/userbase has reached a point where this sort of outage is more likely to occur as a result of slight fluctuations in supernode availability.

Re: Understanding Today's Skype Outage: Explaining Supernodes

#14

Post by eelco »

grammaton wrote: post #13

Is it just me, or does the Skype setup sound an awful lot like Gnutella and it's Ultrapeers back in the day?

It not just you. Skype was founded by the people that also founded KaZaA and they (obviously) took the technology/knowledge they already had, modified it and applied to a different purpose.

Re: Understanding Today's Skype Outage: Explaining Supernodes

#15

Post by mallipeddi »

drats wrote: post #5

My theory: Tons of supernodes (static ip with no NAT, broadband, constantly on) are in the 20s-30s age group and are on holiday. Plus office and university machines that are normally left on have been turned off. The people I know in universities across Europe normally have skype on at work constantly, or at least during the day, and most have static ips on their uni networks so I imagine they get selected as superno…

As they mention on their blog, they botched a significant percentage of their supernodes because of a faulty update they pushed to these clients.

If it was just a side-effect of holiday season, it should happen every year. Also it's likely something like this would maybe cause deterioration of service but not complete disruption for almost the entire user base.

Re: Understanding Today's Skype Outage: Explaining Supernodes

#16

Post by mseebach »

I was wondering if Skype couldn't benefit from a product that is essentially a limited, local supernode.

In my job we try to use Skype video-calls, but the quality is very flaky, which I think is because we rely on someone else relaying us (since both ends are NAT'ed and likely also firewalled). Individually port-forwarding for everybody is unfeasible, but running a single service on a server, and telling everyone to use that as their super-node/proxy would be fine.

Re: Understanding Today's Skype Outage: Explaining Supernodes

#17

Post by danyork »

rix0r wrote: post #9
drats wrote: post #5

My theory: Tons of supernodes (static ip with no NAT, broadband, constantly on) are in the 20s-30s age group and are on holiday. Plus office and university machines that are normally left on have been turned off. The people I know in universities across Europe normally have skype on at work constantly, or at least during the day, and most have static ips on their uni networks so I imagine they get selected as superno…

That could very well be the case, but if that were really the cause you'd expect to see this pattern every year. However, it apparently didn't happen for at least two years in a row[1]. Also, I would have expected Skype engineers to have wised up to the situation by now if it were really a seasonal thing. [1] Since the last outage was 3 years ago. I can't find a source for that right now -- would be interesting to se…

No, the outage in 2007 was in August, and had to do with churn of the supernodes related to updates. I wrote about it here:

http://www.disruptivetelephony.com/2007/08/skype-offers-fu.h...

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