internet telemetry, v6
December 10th, 2008 by kci gave a (faster, less understandable) version of this talk (pdf or slides+audio quicktime) at the October 2008 ARIN meeting in Los Angeles (original October version) and again to ISOC’s advisory council meeting in November. motivation: the end of the current addressing architecture, with scant understanding of how to retain all its positive features in the face of inevitable change. a topic i worry about more each year.
(peter cincotti sings as if we knows what we’re going through.)
March 18th, 2009 at 5:23 pm
About IPv6, worry not. It will not work on the public internet. It will work just fine in private networks (between ISP enterprise/broadband providers and clients). It will work just fine in research labs, and in wireless LANs operated by xbox systems, and in any arrangement where you don’t have to find the globally unique IP address of your destination.
Public internet connections require finding a unicast IP address for the Destination IP address field in the IP header for routing purposes.
Typically, it’s hard to find IPv6 addresses (get a DNS answer) by using a DNS query. Allocations do not matter. Real-time DNS answers matter.
This is because DNS is a hierarchy, and the top of the hierarchy (DNS root) cannot be expressed within a 576-byte packet. All 13 root-names must be contacted for a successful recursive query to this global distributed database.
Even though RFC 3226 was written in 2001, EDNS0 was not implemented in transit devices/software, which continue to limit the DNS UDP size to 512.
Therefore, we cannot contact DNS-root using the IPv6 protocol, cannot get our queries sent to all 13 root-names, and ultimately cannot get an answer to our IPv6 address queries.
No IPv6 address answer, no IPv6 connection. It is that simple.
Look in your measurements. There are many IPv6 address queries. Then look at the response packets. How many IPv6 Address Answers can you find? (Responses often contain redirection to other nameservers – these do not count as Address Answers.)
Show us the data. How many IPv6 Address Answers can you find? What percentage of IPv6 address queries are receiving IPv6 address answers?