Testing IPv6 support on the client's machine (Was: NANOG 40 agenda posted

Nathan Ward nanog at daork.net
Wed May 30 10:38:05 UTC 2007

On 30/05/2007, at 9:46 PM, Stephane Bortzmeyer wrote:

> On Wed, May 30, 2007 at 10:55:04AM +1200,
>  Nathan Ward <nanog at daork.net> wrote
>  a message of 56 lines which said:
>> Use Javascript, or flash, or some other fancy thing to do a GET for
>> two files on two different servers as the page loads:
>> a) http://ip6test.<domain>/file
>> b) http://ip4test.<domain>/file
>> And then compare the hit-rate for the two.
> Very good idea.

> But you should also log the TCP RTT for the two connections because a
> common failure is the fact that IPv4 goes straight to the server while
> IPv6 goes through a tunnel in Thailand or Brazil.

Yep, I plan to do that.

Also the reason that a connection failed (timeout or reject/ 

I suppose that a purpose built server could track things like half  
opened connections (ie. SYNACK probably dropped), open connections  
over which a large-ish request doesn't come (ie. MTU problems), and  
so on.

The implementation problem I find now is that XMLHTTPRequest  
apparently doesn't let you talk to other domains for security  
reasons. I'm going to investigate using nasty iframe hacks, and  
Flash. Maybe Java, but that sounds a bit heavy. If anyone has  
experience with this sort of stuff and can lend some expertise, I'd  
be grateful. Probably offlist would be best for now.

Nathan Ward

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