[ih] Protocol numbers (was IP version 7)

[John Gilmore]

Bob Hinden via Internet-history <internet-history at elists.isoc.org> wrote:
> BTW, I am not sure why 8 and 9 are labeled as historic, but 7 isn't.
> I will ask IANA about this off list.

While we're thinking about it, there is another small field that
threatens to overflow sometime in the foreseeable future, the "Assigned
Internet Protocol Numbers".  These are 8 bits wide, and exist in every IPv4
and IPv6 packet:

  https://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml

The frequently used ones are TCP (6), UDP (17), ICMP (1), etc.  Then
there is the dross.  This registry is already more than half full, and
it lists as actively in use such flashes-in-the-pan as the BR-SAT-MON
(Backroom SATNET Monitoring), the Sun-ND PROTOCOL ("Temporary") from the
early 1980s, Ipsilon Flow Management Protocol, Sprite-RPC from 1986,
CPHB Computer Protocol Heart Beat, Source Demand Routing Protocol, 3PC
3rd Party Connect Protocol, and tons of other things that should have
just gotten a UDP port number assigned from a 16-bit field.  Half of
these protocols don't even have an RFC that defines the protocol.

There is no defined process for reclaiming them, other than having the
original requester write an email to IANA and tell them that it isn't in
use any more.  That seems to be true even if the original requester
worked for a company that the protocol was used by, and the company
still exists (like Sun/Oracle) even though the requester has moved on
decades ago.  Probably, fewer than half of the people who got these
protocol numbers assigned are now dead, but every year creates more
such situations.

I succeeded in asking John Ioannidis to release 2 of the 3 protocol
numbers that he got assigned during the early packet encryption days.
IANA wouldn't just de-allocate them, but they have at least marked them
"deprecated".  JI isn't sure if his IPIP, protocol 94, is in use
anywhere.  We think everybody encapsulating IPv4 in IPv4 or IPv6 packets
is using protocol 4 nowadays, but how would one actually tell?  So 94
remains not deprecated.

When designing IPv6, the designers made the address space huge, but the
protocol space is *smaller* than in IPv4.  Not only do the protocol
numbers used in IPv4 overlap those used in IPv6, but both of them
overlap the "IPv6 extension header" allocation space.  Assigning a new
protocol OR a new extension header burns up space for all three
protocols.

Could anybody who is reading this list, who at one point got a protocol
number assigned, please check if it can be released?  You can search the
above IANA page for your name, to find out if IANA thinks you are in
charge of any.

Or, perhaps notify a retired researcher not on the list, (e.g. is
anybody running Noel Chiappa's CHAOSnet, protocol 16, on top of IP?  Or
Zaw-Sing Su's Packet Radio Measurement protocol 21?  Or the mystery
EMCON protocol 14 with no known contact person or protocol spec?)

And let's together think up a viable way to release the protocols that
were used for some research project, and were then left behind by a
person who has since departed the planet for realms where the protocol
number space is infinite.

	John