I was looking through our network logs and found that one of our devices, a coworker's Apple Watch, was showing up a lot in our DHCP logs – and often too, on the order of dozens of times within a few minutes. Yesterday alone, it requested an IP address from our DHCP server 1220 times. I looked into it a bit more, and had my coworker walk around the office (our main office space is roughly toroidal), and sure enough I saw a DHCP request for every access point from here to there and back again.
I got a list of the number of DHCP requests per day and found a correlation:
June 2nd and before: 2-10 requests per day (usually less than 5)
June 4th: WatchOS 5 Beta 1 released
June 4th to 19th: 550-950 requests per day
June 19th: WatchOS 5 Beta 2 released
June 20th to July 2nd: 10-70 requests per day (usually less than 20)
July 3rd: WatchOS 5 Beta 3 released
July 3rd to July 17th: 200-500 requests per day
July 17th: WatchOS 5 Beta 4 released
My coworker installed Beta 4 this morning, but I saw a huge burst in traffic yesterday (possibly due to meetings, or maybe pre-downloading the upgrade?)
Has anyone else seen this kind of behaviour on their WatchOS test devices? It seems to be a bug or feature change related to WatchOS 5, but I'm not sure why his watch is working so hard to stay on the wifi the whole time.