UDP Broadcasting and the Brave New World of IPv6

After recently working our way through UDP broadcasting and network subnetting all in the comfort zone of IPv4, it’s time to address the elephant in the room, the one wearing …. UDP Broadcasting and the Brave New World of IPv6. Although it’s still very much a rumor at this point, supposedly IPv6 is slated to replace the venerable IPv4 protocol.

Rather than just being IPv4-but-with-more-addresses, its designers took the opportunity to basically completely redesign the protocol for the futuristic world of the late 90s and the early 2000s. Joking aside, IPv6 having been introduced in 1995 and still struggling to meaningfully displace IPv4 does invite some worries about just how easy it is to switch between these two fundamental internet protocols. Say if we wanted to join the future of the 2000s and adapt our software to speak IPv6 instead of IPv4, what would change about the aforementioned aspects of IPv4 UDP broadcasting and IPv4 subnetting.

Speaking as an ignorant developer who mostly knows IPv6 from those weird and hard to remember network addresses, as well as many broken router implementations, I’m not entirely convinced that I’m going to like what I’ll see. Futuristic Broadcasting We saw with IPv4 UDP broadcasting that it was mostly a matter of either determining the network interface’s broadcast address based upon its subnet, or playing things easy mode with the local broadcast address. In the case of IPv6 none of these things exist, however.