[157035] in North American Network Operators' Group
Re: IPv4 address length technical design
daemon@ATHENA.MIT.EDU (Owen DeLong)
Wed Oct 3 19:15:56 2012
From: Owen DeLong <owen@delong.com>
In-Reply-To: <CAAAwwbUPcP_CDEDSpDmu+_FA+d3JZR1tWB+FFf4y0ppzH1kk0g@mail.gmail.com>
Date: Wed, 3 Oct 2012 16:15:04 -0700
To: Jimmy Hess <mysidia@gmail.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Oct 3, 2012, at 3:49 PM, Jimmy Hess <mysidia@gmail.com> wrote:
> On 10/3/12, Jay Ashworth <jra@baylink.com> wrote:
>> So the address space for IPv8 will be...
>> </troll>
>=20
> In 100 years, when we start to run out of IPv6 addresses, possibly we
> will have learned our lesson and done two things:
>=20
> (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.
>=20
Agreed, mostly.
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.
> And
> (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.
>=20
On this, I disagree=85 Once host identifiers are no longer dependent on =
or
related to topology, there's no reason a reasonable fixed-length cannot
suffice.
> Need more bits? No protocol definition change required.
>=20
Nope, just new ASICS everywhere and no clear way to identify where they
are or are not deployed and=85
Owen
