Among all of the other crazy impacts that COVID-19 has had in 2020, I did not expect COVID-19 to change the fundamental protocol mix of packets on the internet. But it did! Read on to find out how.
A tiny primer for those who aren't familiar with IPv6: Every internet connected device has a numeric address; you probably have seen something like "192.168.0.1" at some point. Allowing some hand waving, the original IPv4 addressing scheme has around four billion unique addresses. In the early 1980s when there were a couple dozen devices on the internet, that seemed like a lot, but in 2020, when there are eight billion cell phones in the world, that limitation starts to cause issues. As a fix, the internet is transitioning to IPv6, which has 340 trillion trillion trillion addresses. But it is slow going.
Every so often I will go to Google's IPv6 statistics page and look at the trend of IPv6 usage. If you haven't studied this graph before, let me point out a few interesting things:
The first thing to notice is that IPv6 only really started taking off around 2013. It took a while, considering the original RFC was released in 1995. Back then, it seemed like we were going to run out of IPv4 addresses any day. But it turns out that clever tricks like NAT got us another 20 years of breathing room.
The second thing to notice is that IPv6 is used more heavily on weekends rather than weekdays; you can see this effect between Christmas and New Year's, as well. The usual explanation is that consumer ISPs have rolled out IPv6 to their home customers, but businesses have tons of legacy software that requires IPv4, and there's no financial incentive to change over.
But the most interesting recent development is that you can see this effect starting in March 2020, when COVID-19 mitigations meant that a ton of people started working from home. The difference between weekend and weekday IPv6 usage was cut in half! Obvious in retrospect, but interesting nevertheless.
I'll be the first to admit this isn't scientific by any means--I just thought it was neat. And there are still some mysteries... there's a blip in June that I have no explanation for. I'm a little worried that starting in August, things seem to be slowly trending back to the norm. Is this more workers returning to the office? Or could it be explained by back-to-school? In any case, I'll keep watching the data.
It's now been about 18 months since COVID-19 hit, and about a year since my initial blog entry. Looking at updated graphs, the work-from-home trend has clearly continued to have an impact--the difference between weekend and weekday IPv6 traffic is still smaller than it was in early 2020. On the other hand, the traffic gap is larger than it was during the worst days of COVID, which probably reflects a slow trickle of workers returning to the office.
Looking forwards: IPv6 is slowly getting rolled out to businesses, and workday/weekend IPv6 traffic will eventually converge as that happens. And there is some portion of the workforce that has converted from temporary work-from-home to permanent work-from home, also lessening workday/weekday differences. Once COVID-19 is over, I'll take another look and see where things end up.