Testing Eyeball Happiness Fred Baker
The issue I bring to your attention In dual stack networks, especially if BCP 38 is in use, opening a session can be slow: Code samples using getaddinfo() read: list = getaddrinfo(…); for each address in list Attempt to open a connection If success, break end for That is equivalent to list = getaddrinfo(…); for each address in list sleep (3); end for Common customer support recommendation: “turn IPv6 off and you won’t have that problem”
Papers of interest TCP's Reaction to Soft Errors. Gont. February 2009 RFC 5461, Informational Happy Eyeballs: Trending Towards Success with Dual- Stack Hosts Dan Wing, Andrew Yourtchenko, October 2010 draft-wing-v6ops-happy-eyeballs-ipv6 Opening TCP Sessions in Complex Environments Fred Baker, October 2010 draft-baker-v6ops-session-start-time Testing Eyeball Happiness Baker, November 2010 draft-baker-bmwg-testing-eyeball-happiness
A proposed test: configuration Each LAN is configured with one IPv4 and multiple IPv6 prefixes Alice and Bob have A and AAAA records in DNS Routers have appropriate routing Two routers used to make it easy to null route Alice: Unit under Test DNS Bob: Correspondent Router 1 Router 2
A proposed test: procedure Repeatedly reconfigure Router 1 with various routing: Only IPv4 connectivity Only IPv6 connectivity using each of Bob’s several prefixes Use various blockages: Null route without ICMP (black hole) Null route with ICMP “destination unreachable” Filter with ICMP “administratively suppressed” Alice: Unit under Test DNS Bob: Correspondent Router 1 Router 2
A proposed test: expected outcome Alice should be able to open a session with Bob, starting from the DNS lookup, within a predictable interval, regardless of address choice Not really testing the application – presumed to work in existing networks Outcomes: What is that interval? What is the difference between those intervals Alice: Unit under Test DNS Bob: Correspondent Router 1 Router 2
What I would like from BMWG Sponsorship if bmwg is so inclined Advice on how best to construct the test