uTorrent, IPv6

Nathan Ward nanog at daork.net
Tue Aug 19 23:42:29 CDT 2008

On 20/08/2008, at 6:39 AM, Jay R. Ashworth wrote:
> On Tue, Aug 19, 2008 at 04:56:33PM +1200, Nathan Ward wrote:
>> Sit up and pay attention, even if you don't now run IPv6, or even if
>> you don't ever intend to run IPv6. Your off-net bandwidth is going to
>> increase, unless you put some relays in. As a friend of mine just  
>> said
>> to me: "Welcome to your v6-enabled transit network, whether you like
>> it or not ;-)".
> So you're saying Slashdot *lies*?
> 	http://tech.slashdot.org/article.pl?sid=08/08/18/226228&from=rss

They don't intentionally lie, but the study they are reporting on is  

For example:
"Our research looked at all IPv6 traffic—both native and tunneled,  
including Teredo, which encapsulates IPv4 traffic in UDP
datagrams using UDP port 3544. We found a peak of only 12 Mbps of  
Teredo traffic, representing around 10 percent of the
I P protocol 41 traffic."

Teredo uses 3544/UDP to for Client<->Server communication. That is for  
relay discovery when needed, and the qualification procedure - not  
much traffic. Client<->Relay communication MAY use 3544/UDP, Client<- 
 >Client communication MAY use 3544/UDP.

In my experience (packets I have been analysing in the last 24 hours  
for example) suggests that not many actual data packets are on UDP/3544.
I'll get some exact numbers on that in a few hours if you like.

Also that report only includes data up until July 2008. uTorrent with  
Teredo and IPv6 stuff was released 9 August - which is the intention  
for my original message.

Nathan Ward

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