v6 subnet size for DSL & leased line customers
cmadams at hiwaay.net
Fri Dec 21 17:20:41 UTC 2007
Once upon a time, TJ <trejrco at tjevans.net> said:
> Short answer - no spec for it.
> ARIN breaks it at /56, as a nod towards maybe a /48 for everyone is
> a bit much.
On ARIN's site:
The following guidelines may be useful (but they are only guidelines):
* /64 when it is known that one and only one subnet is needed
* /56 for small sites, those expected to need only a few subnets
over the next 5 years.
* /48 for larger sites
For end sites to whom reverse DNS will be delegated, the LIR/ISP should
consider making an assignment on a nibble (4-bit) boundary to simplify
reverse lookup delegation.
So, the guidelines are on 8 bit boundaries, but then right below they
also suggest making assignments on 4 bit boundaries (and it is all "only
Chris Adams <cmadams at hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.
More information about the NANOG