IPv6 Fragmentation Extension Headers, Part 2

The first part of this article looked at what happens when an authoritative DNS server delivers fragmented UDP responses to DNS resolvers using IPv6. The result from this experiment was that: Some 37% of endpoints used IPv6-capable DNS resolvers that were incapable of receiving a fragmented IPv6 response over UDP.…


Notes from IETF 99 – The Other Bits

After pulling out the notes from the IEPG meeting and aspects of the DNS, here are the rest of the items that I personally found to be of interest at IETF 99 last week. IPv6 Operations – Apple’s Happier Eyeballs? The way in which browsers leverage the potential opportunities offered…


Notes from IETF 99 – The IEPG Meeting

It’s hard to classify the IEPG meetings that occur at the start of the IETF week. Many years ago they had a role in allowing network operators to talk to other operators about what they were seeing and what they were thinking about. Those days are long since over, and…


RIPE 74

RIPE 74 was held in May in Budapest, and as usual it was a meeting that mixed a diverse set of conversations and topics into a very busy week. Here are my impressions of the meeting drawn from a number of presentations that I found to be of personal interest.…


IETF 98 Report

The IETF meetings are relatively packed events lasting over a week, and it’s just not possible to attend every session. Inevitably each attendee follows their own interests and participates in Working Group sessions that are relevant and interesting to them. I do much the same when I attend IETF meetings.…


NANOG 69

NANOG 69 was held in Washington DC in early February. Here’s my notes from the meeting. It would not be Washington without a keynote opening talk about the broader political landscape and NANOG certainly ticked this box with a talk on international politics and cyberspace. I did learn a new…


A Postscript to the Leap Second

The inexorable progress of time clocked past the New Year and at 23:59:60 on the 31st December 2016 UTC the leap second claimed another victim. This time Cloudflare described how the Leap Second caused some DNS failures in Cloudflare’s infrastructure. What is going on here? It should not have been…


Leaving it to the Last Second

Thanks to the moon, the earth’s rate of rotation is slowing down. It’s a subtle interaction and the modelling of planetary dynamics predicts that the earth’s rotation should slowing down by an average of 2.3 milliseconds per century. But this is not quite so uniform, as the Economist reported in…


RIPE 73

RIPE held its 73rd meeting in Madrid in the last week of October. Here are a few of my takeaways from that meeting. What’s behind all those NATs? We suspect that there are at least 10 billion devices connected to today’s Internet, and we know that less than two billion…


BGP Large Communities

IPv4 addresses are not the only Internet number resource that has effectively run out in recent times. Another pool of Internet numbers under similar consumption pressures has been the numbers that are intended to uniquely identify each network in the Internet’s inter-domain routing space. These are Autonomous System numbers (ASNs).…