On Thu, 9 May 2019, Doug Barton wrote:
It's been a while since I was configuring subnets, and last time I did the
guidance was always no more than 1,000 hosts per subnet/vlan. A lot of that
was IPv4 thinking regarding broadcast domains, but generally speaking we kept
to it for dual stacked networks, equating an IPv4 /22 with an IPv6 /64. (This
was commonly in office environments where we used a subnet per floor to
accommodate all of the desktops, printers, phones, tablets, etc.)
Is this still how people roll nowadays? Have switches and/or other network
gear advanced to the point where subnets larger than 1k hosts are workable?
In IPv4 or IPv6? I've done quite a bit of web searching, and can't find
anything newer than 2014 that has any kind of intelligent discussion of this
topic.
It's a good topic to bring up. There has been some work on this in the
IETF, for instance https://tools.ietf.org/html/rfc8273
This means there is single broadcast domain and single /64 per customer,
which if properly implemented helps with a lot of the problem space people
like to solve in this area. It however includes moving away from quite a
lot of what you call "IPv4 thinking".
I however do not operate wifi networks so I have no idea how widely this
is implemented in gear available today. If someone else knows, I would
appreciate if they would share.
--
Mikael Abrahamsson email: [email protected]
