[ih] Memories of Flag Day?

[Vint Cerf]

I think Andrew is correct in this analysis.
v


On Sun, Aug 6, 2023 at 2:32 PM Andrew G. Malis via Internet-history <
internet-history at elists.isoc.org> wrote:

> Brian,
>
> There was a "slight" difference in scale between the two events - several
> hundred ARPANET hosts vs. millions of IPv4 hosts.
>
> But without the stick, at least some subset of ARPANET hosts would have
> decided why bother, as long as we can continue to talk to each other? And
> the ARPANET would definitely have continued as a dual-stack network, as
> hosts that implemented TCP would also have an incentive to keep NCP going
> (other NCP-only hosts). Remember, at that point there wasn't much other
> incentive to implement TCP, as the rest of the Internet hadn't yet started
> to appear.
>
> Cheers,
> Andy
>
>
> On Sun, Aug 6, 2023 at 4:56 PM Brian E Carpenter <
> brian.e.carpenter at gmail.com> wrote:
>
> > Andy,
> >
> > So, it was your fault that we decided that "no flag day" was a vital
> > requirement for IPng :-). Seriously, I think that enough people
> > remembered the 1983 flag day and definitely said "never again!"
> >
> > Regards
> >     Brian Carpenter
> >
> > On 07-Aug-23 04:17, Andrew G. Malis via Internet-history wrote:
> > > Miles,
> > >
> > > I wrote the IMP code to enforce the flag day and ran the transition
> from
> > > the NOC.
> > >
> > > To prepare for the flag day, we added a new bit to each port's
> > > configuration in the IMPs. The bit said whether or not a port was
> allowed
> > > to use the NCP host-host protocol (port 0). If the bit was off, then
> NCP
> > > host-host packets were discarded by the IMPs.
> > >
> > > There was a defined procedure in place well prior to the cutover for
> > > approving exceptions to the no-NCP policy.
> > >
> > > On January 1, I pulled the switch to flip the bits from "on" to "off"
> > > except for the pre-approved list of exceptions.
> > >
> > > A good number of hosts made the deadline, but additional exceptions
> were
> > > approved as the phone calls started coming in. The exception list
> > continued
> > > to grow in the first few days of 1983, but as hosts gradually got their
> > > TCP/IP stacks working, their NCP permission was turned off.
> > >
> > > As I recall, the exception list quickly shrank, and by the end of the
> > year
> > > there were very few NCP-only hosts left. There was certainly some
> amount
> > > of pain involved, but NCP would have hung around for much longer if the
> > > switchover hadn't been enforced.
> > >
> > > Cheers,
> > > Andy
> > >
> > >
> > > On Sun, Aug 6, 2023 at 7:35 AM Miles Fidelman via Internet-history <
> > > internet-history at elists.isoc.org> wrote:
> > >
> > >> Hi Folks,
> > >>
> > >> Does anybody have some memories of the TCP/IP Flag Day they can share?
> > >>
> > >> I'm doing some writing about "how network ecosystems develop" looking
> at
> > >> how the Internet evolved from the days the net was a gleam in a few
> > >> people's eyes, Licklider distributed his famous memo, the NWG & IETF
> > >> evolved, Flag Day, etc.  Also looking at the Environmental Movement
> > >> (Earth Day, Whole Earth Catalog, ...), FOSS, Crisis Mapping,
> > >> Entrepreneurship Support, Makers - all of which I've been up close and
> > >> personal with, and now trying to document some common threads &
> > techniques.
> > >>
> > >> A particular focus is on organizing for significant
> > >> changes/transformations - like the transition to IP that pretty much
> > >> marks the birth of the Internet as we know it.  Hence a particular
> > >> interest in what led up to the Flag Day, and how folks responded.
> > >>
> > >> In particular, I'm wondering how folks organized at various network
> > >> sites (universities, military bases, etc.) to respond to the mandate.
> > >> Working groups, plans & programs, that sort of thing. How did folks
> get
> > >> their act together?
> > >>
> > >> Anybody have any stories they can share?
> > >>
> > >> Thanks Very Much,
> > >>
> > >> Miles Fidelman
> > >>
> > >> --
> > >> In theory, there is no difference between theory and practice.
> > >> In practice, there is.  .... Yogi Berra
> > >>
> > >> Theory is when you know everything but nothing works.
> > >> Practice is when everything works but no one knows why.
> > >> In our lab, theory and practice are combined:
> > >> nothing works and no one knows why.  ... unknown
> > >>
> > >> --
> > >> Internet-history mailing list
> > >> Internet-history at elists.isoc.org
> > >> https://elists.isoc.org/mailman/listinfo/internet-history
> > >>
> >
> --
> Internet-history mailing list
> Internet-history at elists.isoc.org
> https://elists.isoc.org/mailman/listinfo/internet-history
>


-- 
Please send any postal/overnight deliveries to:
Vint Cerf
Google, LLC
1900 Reston Metro Plaza, 16th Floor
Reston, VA 20190
+1 (571) 213 1346


until further notice