And now, for your regularly scheduled dose of broken ipv6 routing...

Iljitsch van Beijnum iljitsch at
Sun Sep 24 19:07:45 CEST 2006

On 22-sep-2006, at 10:16, Carlos Friacas wrote:

> Recently i've started to measure v4 and v6 latency to the same host  
> (or to the same name with both A and AAAA records) and found that  
> it's really, really hard to find names with both A and AAAA in some  
> countries (and yes, *even* in the academic communities...)

> For what i've seen so far, the measurements i get with a smaller  
> difference than 1ms between v4 & v6 are from other NRENs (to be  
> more accurate... 13 of them to the date). Could be better, could be  
> worse...

I have to disagree here. It all depends on your vantage point. Within  
the commercial IPv6 internet, the difference between IPv4 and IPv6 is  
probably a bit bigger than within the academic networks, BUT...  
apparently, the academic networks as a group refuse to take good  
peering and transit to the commercial world in IPv6, so going between  
the two sucks big time in many cases.

I was going to show you that from my system to IPv6 is  
worse than IPv4, but I don't get any ping replies over IPv4 so never  

I'll be interested to see how this one is for you:

[alumange:~] iljitsch% ping -c 25
PING ( 56 data bytes
25 packets transmitted, 25 packets received, 0% packet loss
round-trip min/avg/max/stddev = 168.561/187.332/250.520/17.626 ms

[alumange:~] iljitsch% ping6 -c 25
PING6(56=40+8+8 bytes) 2001:1af8:6::20a:95ff:fef5:246e -->  
25 packets transmitted, 25 packets received, 0% packet loss
round-trip min/avg/max = 186.890/255.224/635.499 ms

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