I don't see how this would be new information for blizzard, if you are on a public DNS (like college dorm) i could see it is bad that randoms can join you but if your bots see each other? I am sure blizzard has always been able to match bots by IP they just never choose to use it as reason for bans.
Each bot - unique private IP. Unique MAC. Different subnets.
Don't want to dig into tech details. If they wish they could end botting right now, and there is much more otherways doing in. Not related to network and stuff.
Yet, this. I just don't like it, maybe it was ages ago and its just us didn't know that. But my paranoia helps me bot since summer, and I had only small percent of bans on december, where a lot were hit. And me not exception too.
From what I can see, D3 sends UDP broadcast on 6120 port, (its just one packet) and receives replies.
There is some data in it, use wireshark who interested, not sure if it is sensitive but im 100% sure that its results, lets bnet service give you near players list, so per say, its server sided feature. Yet again, dont like it.