[12574] in North American Network Operators' Group
Re: Packets from net 10 (no, not the lyrics)
daemon@ATHENA.MIT.EDU (Mohamad Eljazzar)
Tue Sep 23 12:43:27 1997
Date: Tue, 23 Sep 1997 12:29:00 -0400 (EDT)
From: Mohamad Eljazzar <eljazzar@ns.utk.edu>
To: bmanning@ISI.EDU
cc: nanog@merit.edu
In-Reply-To: <199709231554.AA05559@zed.isi.edu>
On Tue, 23 Sep 1997 bmanning@ISI.EDU wrote:
> >
> > What about providers that use portions of the private address space on
> > their network (up to and including the client's serial interface)?
> >
> > Mohamad
> >
> > On Tue, 23 Sep 1997 bmanning@ISI.EDU wrote:
> >
> > > > Should I be filtering all reserved space at my border, or would
> > > > it be reasonable for me to expect the big guys not to take packets
> > > > with clearly inappropriate source addresses?
> > >
> > > Yes you should. (and with kudos to Andrew)
> > >
[ access lists deleted ]
> > >
>
> The operative phrase here is border.
> That means ASN border, i.e. where you BGP
> peer with others. At the provider/subscriber
> interface, within your IGP, using RFC 1918 space
> is ok.
I agree if BGP is running between the customer and the provider. However,
if:
- both the provider *and* the customer are using the same private
address space
*and*
- the provider assigns the p2p link addresses from that same
address space (according to its own subnetting plan)
the question becomes: where do you apply the filters? Is it safe for the
provider to assume, in the first place, that its use of private addresses
should extend to customer networks?
Mohamad
