Re: Odd packet?

[Steffen Schumacher <ssch () wheel dk>]

On 26.05.2004 11:28:37 +0000, Valdis.Kletnieks () vt edu wrote:
> On Tue, 25 May 2004 22:35:25 +0200, Steffen Schumacher said:
>
> > However, as you said, no ISP, which has to follow rules and regulations in the
> > western world allows spoofing of or even routing of the 127/8 net.
>
> 1) There's no law or regulation that *requires* an ISP to not route 127/8.

Right you are.. however in rfc 1700:

Reynolds & Postel                                               [Page 4]
^L
RFC 1700                    Assigned Numbers                October 1994


      (e)   {<Network-number>, <Subnet-number>, -1}

         Directed broadcast to specified subnet.  Can only be used as
         a destination address.

      (f)   {<Network-number>, -1, -1}

         Directed broadcast to all subnets of specified subnetted
         network.  Can only be used as a destination address.

      (g)   {127, <any>}

         Internal host loopback address.  Should never appear outside
         a host.

The way I read this, then an ISP should be disturbed if there were ever reports
of seeing such pakets in their network. Furthermore why should they have routes 
to addressspace which shouldn't be used outside a node?
The ISP are in a sense implementers of an IP network, and they should conform to
RFC1700. But you're right! its no law.. along with IP..
 
> 2) The *source* of the packet was 127.0.0.1, and routing is done on the *destination*.

Really? It's amazing I got this job then!! Just kidding.. 
the 'or even routing' was a mere sidenote, but maybe that didn't shine through 
very well.. Sorry about that..
 
> 3) An amazing number of ISPs do *not* do proper ingress/egress filtering.

I'm beginning to hear that - I stand corrected!

/Steffen
 


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