The benefits of deploying IPv6 only

"Use of IPv6 is gaining momentum. For some companies it is the primary IP version of choice to run their businesses and to deliver products and services to their customers. The depletion of globally routable IPv4 and private IPv4 address space has prompted many technology firms to look at the use of IPv6 while abandoning support for IPv4 in some parts of their networks. Additionally, and perhaps, more interestingly IPv6 has been rumored to outperform IPv4. New data is available from more diverse adopters that further substantiates these claims."

Notes:

FB is IPv6 internally. Networking said "we're out of RFC1918, time to move."

Decided to make it all v6 and no v4 to avoid having to manage two stacks and to commit TCAM to both network representations. Simpler for them to go with one system. Converted all apps to IPv6 and are entirely IPv6 now.

Facebook claims that their metrics are showing better performance for IPv6 vs IPv4. They speculate that the absence of middleboxes (NATs, etc.) is a probable cause. They are going to look into it more and force users to use happy eyeballs to see if these results hold up. iOS is v4/v6 capable so they are using that as testbed.  FB still trying to get to quad-A NS records and will have them in a few months. Took them several years to get to IPv6.

FB metrics show different graphs of IPv6 traffic vs v4 because corporate american doesn't have v6. Over 12 percent of FB traffic is v6. iOS will only select v6/happy eyeballs 20 percent of the time over a given path.

FB "multiproxygen" will use v6 80 percent of the time because of faster perf.

FB app has its own stack. FB wrote it to avoid having network perf issues across multiple platforms. Same stack they use on all their own servers. Write once, use everywhere. They were able to make IPv6 work before support on various platforms. FB hopes to opensource this. Apple is treating v6 like a second class citizen, but FP app works they way FB wants WRT v6 because of the internal stack.

Interesting result of this session is that big outfits, FB and other providers, have gone to v6 internally and shut off v4 when they can to simplify and avoid costs. Must be nice to have total control of your internal environment.