Re: Martian and RFC1918 addresses

[Philip Smith <pfs () cisco com>]

The list we documented in IOS Essentials was one presented a few (I don't
remember how many) IEPGs ago, and was implemented by several ISPs... Indeed
the next version of the document mentions only those listed in Bill's draft
- I'd suggest we all stay with that as it is probably the first attempt to
document non-routable nets...

I don't remember the history of the other network blocks listed anymore,
certainly not without a lot of e-mail archive trawling...

philip
--

At 19:57 29/07/99 -0400, Daniel Senie wrote:
> rfuller () 3x com wrote:
> > I have been reading Cisco's "Essential IOS Features Every ISP Should
> > Consider" document and came across a section called Martian and RFC1918
> > networks.  It is discussing different bogus or reserved networks that
> > should be filtered by every ISP.  In the list are some addresses I thought
> > were legal and after checking the ARIN Whois database, some of them seem to
> > be.  Can anyone give me some additional information as to the need to
> > filter the following networks:
>
> Some of these are indeed questionable. I recommend using Bill Manning's
> draft on this subject (draft-manning-dsua-01.txt) as a guide, rather
> than Cisco's document. Page 27 of Cisco's document has a sample
> access-list which does match Bill's document. Page 59 of the document
> has the list you saw and were concerned about. It claims the information
> comes from the NANOG list. Hmmm...
>
> > 1.0.0.0             reserved for IANA
> > 19.255.0.0          this belongs to Ford
> > 59.0.0.0            reserved for IANA
> > 129.156.0.0         this belongs to SUN
>
> > 169.254.0.0         IANA use for local link numbers???
>
> 169.254/16 should never be routed. It's used for self assigned
> addresses, and is useful in small networks especially. Win98 takes
> advantage of this if DHCP fails to find a server. It allows a small
> cluster of systems to select unique IP addresses, and in the case of
> Windows, they'll then talk Netbios over IP on that. It eliminates the
> need to use Netbeui, which in itself is a good thing.
>
> > 192.0.2.0      reserved for IANA
>
> 192.0.2/24 is set aside for use in documentation and examples. By
> ensuring this block is not routed, folks who type the exact values from
> their documentation don't screw up someone else's network.
>
> > 192.5.0.0      no ARIN match
> > 192.9.200.0         no ARIN match
> > 192.9.99.0          this belongs to SUN
> >
> > If you can elaborate on what they are used for and if any problems would
> > arise from filtering these networks, it would be appreciated.  If you could
> > also please include where you found the information, I would appreciate it.
> > Some of them belong to companies, so why would you filter them?  Are they
> > development networks for Ford and SUN?  Are there any other martian
> > networks that should be filtered?
>
> Lots of folks used to set up their Sun workstations on private networks
> using Sun's IP space, 'cause that's what was in the Sun documentation.
> The only thing I can figure is the other blocks in the example must be
> ones that were frequently used in documentation and got used in a lot of
> private networks that later connected to the public network. Anyone have
> better insight into these?
>
> -- 
> -----------------------------------------------------------------
> Daniel Senie                                        dts () senie com
> Amaranth Networks Inc.            http://www.amaranthnetworks.com