fanf | Amsterdam day 5 (Reply)

I was out late last night so I'm writing yesterday's notes this morning.

Yesterday I attended the DNS and MAT meetings, and did some work outside the meetings.

CDS

Ondřej Caletka presented his work on keeping DNS zone files in git.

Lots of my favourite tools :-) Beamer, Gitolite, named-compilezone
How to discover someone has already written a program you are working on: search for a name for your project :-)

BCP 20 classless in-addr.arpa delegation led to problems for Ondřej: RFC2317 suggests putting slashes in zone names, which causes problems for tools that want to use zone names for file names. In my expired RFC2317bis draft I wanted to change the recommendation to use dash ranges instead, which better matches BIND's $GENERATE directive.

At the end of his talk, Ondřej mentioned his woork on automatically updating the RIPE database using CDS records. As planned, I commented afterwards in support, and afterwards I sent a message to the dns-wg mailing list about CDS to get the formal process moving.

DNS tooling

I spoke to Florian Streibelt who did the talk on BGP community leaks on Tuesday. I mentioned my DNS-over-TLS measurements; he suggested looking for an uptick after christmas, and that we might be able to observe some interesting correlations with MAC address data, e.g. identifying manufacturer and age using the first 4 octets of the MAC addresss. It's probably possible to get some interesting results without being intrusive.

I spent some time with Jerry Lundstrom and Petr Špaček to have a go at getting respdiff working, with a view to automated smoke testing during upgrades, but I ran out of battery :-) Jerry and Petr talked about improving its performance: the current code relies on multiple python processes for concurrency.

I talked to them about whether to replace the doh101 DNS message parser (because deleting code is good): dnsjit message parsing code is C so it will require dynamic linking into nginx, so it might not actually simplify things enough to be worth it.

DNS miscellanea

Ed Lewis (ICANN) on the DNSSEC root key rollover

next step is January 11 when the old key gets revoked and the DNSKEY response size will grow a few bytes bigger than it has been before
Geoff Huston says see http://www.potaroo.net/ispcol/2017-08/xtn-hdrs.html and http://www.potaroo.net/ispcol/2016-11/rootstars.html for information about the risks of the large response size

Petr Špaček (CZ.NIC) on the EDNS flag day, again

"20 years is enough time for an upgrade"

Ermias Malelgne - performance of flows in cellular networks

DNS: 2% lookups fail, 15% experience loss - apalling!

Tim Wattenberg - global DNS propagation times

zero TTLs actually work! (with caveats!)
https://ismydnslive.com/ propagation checker using RIPE Atlas

Other talks

Maxime Mouchet - learning network states from RTT

traceroute doesn't explain some of the changes in delay
nice and clever analysis

Trinh Viet Doan - tracing the path to YouTube: how do v4 and v6 differ?

many differences seem to be due to failure to dual-stack CDN caches in ISP networks

Kevin Vermeulen - multilevel MDA-lite Paris traceroute

MDA = multipath detection algorithm
I need to read up on what Paris traceroute is ...
some informative notes on difficulties of measuring using RIPE Atlas due to NATs messing with the probe packets