Please also see my IETF 98 updates from Monday, Wednesday and Friday.

I arrived in Chicago on Saturday evening to participate in the IETF 98 meeting. It hasn’t stopped raining since I got here. Only the bottom half of the city is visible, most skyscrapers have disappeared in the clouds. Luckily I will be stuck in meeting rooms for the rest of the week.

Chicago in the mist

The IEPG: operators meet at the IETF

Sunday morning has traditionally been reserved for the IEPG meeting where operators come together and update each other on the latest developments. IEPG originally stands for Internet Engineering Planning Group, but the scope has shifted slightly over the years.

The meeting was kicked off by Giovane Moura who has also been a RIPE Labs contributor in the past. Giovane and his colleagues did a study to find out "if Let's Encrypt is democratising encryption". They concluded that the project is indeed a success story: it reduces costs and complexity and therefore helps to democratise encryption. You can find the full study in this paper. There is still some future work to do, for instance extending the measurement period. The group would also like to measure the use by malicious actors.

Ondřej Surý from CZ.NIC presented what he called "The DNS Horror Show". Together with his colleagues he compiled a pretty long list of DNS protocol violations. With that, he wants to make the DNS better, share knowledge and help others to avoid common pitfalls and mistakes. Ondrej said that it might be time for more drastic action: we should remove the workarounds and stop resolving the most blatant DNS violations. "Standards are standards and need to be followed." But on the other hand, the DNS community needs to be inclusive and explain to people what they are doing wrong. You can find more on the DNS violation pages on github. There is also a mailing list.

Next Geoff Huston presented his study on "Routing in 2016". You can find the whole paper and many interesting graphs in this RIPE Labs article. Growth in IPv4 is pretty consistent. People seem to be relying on NATs however. Geoff predicts that we might be getting to a million BGP table entries in 2023 if the NATs hold up. Growth in IPv6 is still there, but in relative terms it is slowing down. Predictions, however, are really hard. Bottom-line: as long as silicon keeps increasing, there won't be a routing table crisis. However, the number of unstable routing table entries (announcements and withdrawals) are surprisingly stable over the last ten years. That also means that convergence performance in IPv4 has not changed during that time (it is about 50 seconds). This is completely different in IPv6: the noise level there is amazing.

Last, but not least, Job Snijders brought up the issue of interface prefix length and routing. As an operator, Job is very firm on the view that operations realities in BGP and at the Internet Exchange Point demand that BGP speakers are free to use any prefix length they need (subject to the normal constraints in the operational community). However, quite a few people in the IETF feel that there are more proscriptive limits on what can be done, and that the interface prefix length is bound to a /64, to a /127, and sometimes (depending on which draft and RFC and BCP you read) either. The core issue relates to the overwhelming majority of devices which assume a /64 for SLAAC, which is different to the flexibility operational deployment managers feel they need (e.g. to limit neighbour discovery exhaustion). The real discussion is taking place on the lists of both operators groups and the relevant IETF WG, and we can expect more fireworks for some time.

Sunday Tutorials

I have chaired the Edu Team that organises a series of tutorials at every IETF meeting for more than ten years. It started with a tutorial for IETF newcomers. Later the scope was expanded to "whatever enables IETF participants to make good protocols". This time we offered four tutorials:

• Newcomers tutorial (by Mike St.Johns)
• The Independent Stream: An Introduction (by Nevil Brownlee)
• Security Considerations (by Chris Inacio and Rich Salz)
• QUIC - A New Internet Transport (by Jana Iyengar and Ian Swett)

In addition to these tutorials, there are also a number of activities targeted towards IETF newcomers. This time I participated in the speed mentoring which was great fun. You get to talk to many newcomers coming to the IETF from all over the world and with various backgrounds. I spoke to people from Nepal, India, Australia and Brazil who were interested in topics such as security, routing, mail and censorship.

Unfortunately I only had the chance to attend one of the tutorials this afternoon: QUIC. It was an excellent presentation covering the history of the QUIC protocol, the problem statement and the current work of the IETF QUIC Working Group. There was a lot of interest and the room was packed.