Re: [wg-pic] Tolly's Skype critique

[Sven Abrahamse <>]

would be really nice to see what the inside scoop of skype is :-)

 

S

 

On 9/30/05, Doug Pearson <> wrote:

Anyone have a good reference to the inside technical details of how Skype works?

The Tolly article says "dearth of information available to us, we learned most of what we know by studying Skype 'in the wild'"... but it doesn't share much about those details.

Doug Pearson


At 04:01 PM 9/29/2005 -0400, Ben Teitelbaum wrote:
>Candace Holman <> writes:
>
>> In this article, Tolly studied Skype peer-to-peer traffic to evaluate
>> the impact on network bandwidth.  He quoted the Skype Web site on what
>> peer-to-peer means: "A true [peer-to-peer] system, in our opinion, is
>> one where all nodes in a network join together dynamically to
>> participate in traffic routing-, processing- and bandwidth-intensive
>> tasks that would otherwise be handled by central servers." Interesting
>> view.  Tolly suggests that this means your Skype-enabled workstation
>> may be functioning as a traffic relay for otherwise-centralized call
>> processing, conferencing, voice mail, etc.
>
>That seems like a fair definition of "true peer-to-peer" to me.  One
>of the big reasons that universities may see a lot of Skype traffic is
>the use of public IP addresses.  Skype needs a share of its users to
>be non-NATted to serve as media relays for hosts behind
>tricky-to-traverse NATs.
>
>-- ben
>
>--
>Ben Teitelbaum   http://people.internet2.edu/~ben/