Has PSI been assigned network 1?

Curtis Villamizar curtis at ans.net
Tue Apr 18 16:50:17 UTC 1995

In message <199504180716.AA12431 at interlock.ans.net>, Hank Nussbacher writes:
> On Mon, 17 Apr 1995 12:00:24 -0400 you said:
> >Curtis
> >
> >BTW- You might try a traceroute to an address in 140.222/16.  That's
> >the ANS backbone.  For example, traceroute would verify
> >that you could reach ANS NY POP.  Traceroute would give
> >you a !H as soon as you reach an ANS interface (look for t3.ans.net in
> >the DNS if the response is not from a 140.222 address).
> Will continue to work?  We 'ip default-network'
> and will have to change if this NSFnet backbone net ceases to exist.
> I would bet lots of smaller ISPs have this net out there in their
> routing tables as gateway of last resort.
> Thanks,
> +---------------------------------------------------------------+
> |                        Hank Nussbacher                        |
> | Inter-University Computer Center   IBM                        |
> | Tel-Aviv University                Rechov Weizmann 2
> | Ramat Aviv     ISRAEL              Tel Aviv      ISRAEL       |
> |                                                               |
> | Work phone: +972-3-6408309         Work phone: +972-3-6978852 |
> | Work fax:   +972-3-6409118                                    |
> |                 Home phone: +972-9-920165                     |
> |                 Home fax:   +972-9-920166                     |
> |                                                               |
> | Internet: hank at vm.tau.ac.il    or  hankn at vnet.ibm.com         |
> |                                                               |
> |        Crash dummy of the Israeli Information Highway         |
> +---------------------------------------------------------------+

The network number 140.222/16 will continue to be the address of the
ANS backbone.  This network is not going away any time soon.  The only
conceivable reason (long term maybe - no plan at this point) we might
get rid of 140.222 would be if we could compress all our routers and
interface numbers into a smaller prefix and wanted to be really good
CIDR citizens and renumber our backbone.  (very unlikely unless the
number allocation problem becomes critical in the years to come).

You might be better off directing a default route at your primary
provider, though aiming at 140.222 won't make much difference from a
distance in the topology.  We are aware of the widespread use of
140.222 among smaller providers.  Unlike 129.40 (the former T1
backbone, later reassigned to IBM Kingston), 140.222 is not being

The one practice ANS is trying to stop is our immediate peers pointing
a default route at us for the purpose of gaining free transit
connectivity to other providers pointing default at other
interchanges.  To my knowledge, though we are unhappy with the
practice, no shutdown ultimatims have been issued.


PS - I don't think any provider will be losing connectivity to 140.222
in the upcoming transition, but would stand corrected if anyone has
better information.

PPS - Nice .sig "Crash dummy of the Israeli Information Highway".  :-)

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