After spending a lot of hours on Skype voice calls over the last few days, I got curious on how much bandwidth Skype uses for voice calls and whether it’s really worth setting up a VOIP server to get a dedicated VOIP number.
On the Skype website they say:
Skype automatically selects the best codec depending on the connection between yourself and the person you are calling. On average, Skype uses between 3-16 kilobytes/sec depending on bandwidth available for other party, network conditions in between, callers CPU performance, etc.
That’s about 10.54 MB to 56.25 MB per hour which is not bad at all.
After browsing through the Skype forum, people quoted numbers that are way different than the above numbers and speculated on how exactly the Skype protocol works.
The Skype protocol does not use a straight SIP protocol, instead it uses a Peer-to-Peer Internet Telephony protocol which was developed by KaZaa in 2003. Doesn’t that send a chill down your spine? KaZaa was well known for infecting PCs with adware in order to keep themselves in business (whatever that business was)
Kazaa is commonly used to exchange MP3 music files over the Internet. However it can also be used to exchange other file types, such as videos, applications, and documents. The official Kazaa client can be downloaded free of charge, however, it is bundled with adware and spyware, even though there are “No spyware” claims found on Kazaa’s website. Throughout the past few years, Kazaa’s developing company has been the target of many copyright-related lawsuits.
Luckily eBay bought out Skype in September 2005 (for 2.6 Billion), although I doubt KaZaa would really have gone as far as to use Skype as a piece of Zombie software (my definition for software that has two purposes, one is to be useful in some way and second is to infect PCs that find these services useful)
Two computer scientists, Salman Baset and Henning Schulzrinne reverse engineered the Skype protocol back in 2004 and posted a paper on their findings if you’re interested in completely understanding the Skype protocol and why it uses more bandwidth in some cases (when you’re a supernode for example): cucs-039-04
An old version of Skype, version 2.5 reverse engineered on low level if you’re REALLY interested in understanding what’s going on under the hood: vskype-part1 & vskype-part2
Trying to measure it using netmeter is giving inconclusive results, the amount of bandwidth being used is varying too much to be able to give exact figures, I guess that’s the way it is with P2P protocols.
Not bad. I thought it used way more.
Kazaa, when i had my first computer i was usually on Kazaa, I had the version that was without the bad stuff, the first versions were really cool until they got bought by that other company.
Oh yes, there were a few people that got fed up with the badware and made Kazaa++ That’s the one i used to work with
The good ol’ days of dial-up, lol
haha, I remember that, it was 56k line and my parents paid R6k the one month because of me downloading out of “free” hours
Sheesh, that’s heavy man, the biggest phone bill I managed to cause was about R2500, never had any of that weekender plus or free minute stuff (I blamed it on varsity work, lol)
The Estonian who invented kazaa went on to invent skype. Same boys.