IPv4 address length technical design
owen at delong.com
Wed Oct 3 23:15:04 UTC 2012
On Oct 3, 2012, at 3:49 PM, Jimmy Hess <mysidia at gmail.com> wrote:
> On 10/3/12, Jay Ashworth <jra at baylink.com> wrote:
>> So the address space for IPv8 will be...
> In 100 years, when we start to run out of IPv6 addresses, possibly we
> will have learned our lesson and done two things:
> (1) Stopped mixing the Host identification and the Network
> identification into the same bit field; instead every packet gets a
> source network address, destination network address, AND an
> additional tuple of Source host address, destination host
> address; residing in completely separate address spaces, with no
> "Netmasks", "Prefix lengths", or other comingling of network
> addresses and host address spaces.
Prefix lengths can still be useful for route summarization and it would
be useful to have separate segments of the network address, such as
Autonomous System Number, Intra-AS Organizational Identifier, and
Intra-Organizational Network, for example. It might be useful to use
prefix lengths in those cases to allow for variability in the boundary
between these identifiers.
> (2) The new protocol will use variable-length address for the Host
> portion, such as used in the addresses of CLNP, with a convention of
> a specified length, instead of a hardwired specific limit that comes
> from using a permanently fixed-width field.
On this, I disagree… Once host identifiers are no longer dependent on or
related to topology, there's no reason a reasonable fixed-length cannot
> Need more bits? No protocol definition change required.
Nope, just new ASICS everywhere and no clear way to identify where they
are or are not deployed and…
More information about the NANOG