Bogon list

Daniel Senie dts at senie.com
Fri Jun 7 14:51:40 UTC 2002


At 05:26 AM 6/7/02, Stephen J. Wilcox wrote:


>On Thu, 6 Jun 2002, Stephen Griffin wrote:
>
> >
> > In the referenced message, Sean M. Doran said:
> > > Basically, arguing that the routing system should carry around
> > > even more information is backwards.  It should carry less.
> > > If IXes need numbers at all (why???) then use RFC 1918 addresses
> > > and choose one of the approaches above to deal with questions
> > > about why 1918 addresses result in "messy traceroutes."
> > >
> > > Fewer routes, less address consumption, tastes great, less filling.
> > >
> > >     Sean.
> >
> > Do you:
> > 1) Not believe in PMTU-D
>
>RFC1918 does not break path-mtu, filtering it does tho..

Though many people either miss the point or don't care, RFC 1918 is also 
BCP 5. Last I checked, BCP stood for "Best Current Practice." So you've got 
a BCP document saying the addresses listed in RFC 1918 should not be 
present on the public network. So yes, filtering is required by RFC 1918, 
and so use of the private IP address blocks does break Path MTU discovery. 
Some folks find the private address space specified in RFC 1918 convenient, 
but ignore the stipulations on use contained in the same document.

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Daniel Senie                                        dts at senie.com
Amaranth Networks Inc.                    http://www.amaranth.com




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