On Tuesday 14 October 2008, Pyda Srisuresh wrote:
> Thanks, Julien. This is a good data point. DO you know if the network
> has NAT devices, that also respond to the router discovery messages?

To my knowledge the network had no NAT devices.

--julien

> --- On Tue, 10/14/08, Julien Laganier 
<[EMAIL PROTECTED]> wrote:
> > From: Julien Laganier <[EMAIL PROTECTED]>
> > Subject: Re: [Int-area] [BEHAVE]  WGLC:
> > draft-ietf-behave-nat-icmp-09 To: [email protected],
> > [EMAIL PROTECTED]
> > Cc: "Behave WG" <[EMAIL PROTECTED]>, "Fernando Gont"
> > <[EMAIL PROTECTED]>, [EMAIL PROTECTED] Date: Tuesday,
> > October 14, 2008, 4:07 AM
> > Suresh,
> >
> > FWIW, I've seen ICMP router discovery being used
> > extensively in at least
> > one large managed network.
> >
> > --julien
> >
> > On Monday 13 October 2008, Pyda Srisuresh wrote:
> > > Folks,
> > >
> > > The "Router advertisements and
> >
> > solicitations" message appears to be
> >
> > > rarely used in Ipv4 networks. Please let me know if
> >
> > anyone has
> >
> > > objections to changing the requirement for this
> >
> > message to MAY from
> >
> > > MUST for NATs. If I dont hear any objection, I will
> >
> > convert this to
> >
> > > MAY in the next rev of the draft.
> > >
> > > Thanks.
> > >
> > > regards,
> > > suresh
> > >
> > > --- On Wed, 10/8/08, Pyda Srisuresh
> >
> > <[EMAIL PROTECTED]> wrote:
> > > > From: Pyda Srisuresh <[EMAIL PROTECTED]>
> > > > Subject: Re: [BEHAVE] [Int-area] WGLC:
> > > > draft-ietf-behave-nat-icmp-09 To: "Behave
> >
> > WG" <[EMAIL PROTECTED]>,
> >
> > > > "'Internet Area'"
> >
> > <[email protected]>, "Fernando Gont"
> >
> > > > <[EMAIL PROTECTED]> Cc:
> >
> > [EMAIL PROTECTED]
> >
> > > > Date: Wednesday, October 8, 2008, 10:49 PM
> > > > --- On Wed, 10/8/08, Fernando Gont
> > > >
> > > > <[EMAIL PROTECTED]> wrote:
> > > > > From: Fernando Gont
> >
> > <[EMAIL PROTECTED]>
> >
> > > > > Subject: Re: [BEHAVE] [Int-area] WGLC:
> > > >
> > > > draft-ietf-behave-nat-icmp-09
> > > >
> > > > > To: [EMAIL PROTECTED], "Behave
> >
> > WG"
> >
> > > > <[EMAIL PROTECTED]>, "'Internet
> >
> > Area'"
> >
> > > > <[email protected]>
> > > >
> > > > > Cc: [EMAIL PROTECTED]
> > > > > Date: Wednesday, October 8, 2008, 5:37 PM
> > > > > Hello, Pyda,
> > > > >
> > > > > Comments in-line...
> > > > >
> > > > > > > >    REQ-9: A NAT device MAY
> >
> > implement a
> >
> > > > > policy control
> > > > >
> > > > > > > that prevents
> > > > > > >
> > > > > > > >    ICMP messages being
> >
> > generated toward
> >
> > > > > certain
> > > > >
> > > > > > > interface(s).
> > > > > > >
> > > > > > > >    Implementation of such a
> >
> > policy
> >
> > > > control
> > > >
> > > > > overrides
> > > > >
> > > > > > > the MUSTs in
> > > > > > >
> > > > > > > >    REQ-10.
> > > > > > >
> > > > > > > Then.... shouldn't the
> >
> > requirements be
> >
> > > > > > > "SHOULD"s rather than
> > > > >
> > > > > "MUST"s?
> > > > >
> > > > > >[suresh] Essentially, the objective is
> >
> > not to
> >
> > > > dilute
> > > >
> > > > > the MUST or
> > > > >
> > > > > >SHOULD requirement on the NAT device,
> >
> > but to give
> >
> > > > the
> > > >
> > > > > device admin
> > > > >
> > > > > >an override capability. So, if the admin
> >
> > chooses
> >
> > > > to
> > > >
> > > > > enforce local
> > > > >
> > > > > >policies to override NAT operation, then
> >
> > the NAT
> >
> > > > device
> > > >
> > > > > MAY enforce
> > > > >
> > > > > >the local policy control. Would the
> >
> > following
> >
> > > > revised
> > > >
> > > > > wording work for you?
> > > > >
> > > > > >Implementation of such a policy control
> >
> > overrides
> >
> > > > the
> > > >
> > > > > MUSTs and
> > > > >
> > > > > >SHOULDs in REQ-10.
> > > > >
> > > > > Any would work for me. I was just wondering
> >
> > if it was
> >
> > > > > correct (from a
> > > > > the perspective of RFC2119) to include a
> >
> > MUST that
> >
> > > > could be
> > > >
> > > > > overiden.
> > > > > That is, I was wondering if that means that
> >
> > the
> >
> > > > > "requirements" should
> > > > > be a "SHOULD" rather than a
> > > >
> > > > "MUST".
> > > >
> > > > > > > >           5. Router
> >
> > Advertisement and
> >
> > > > > Solicitations,
> > > > >
> > > > > > > as described in
> > > > > > >
> > > > > > > >              Section 4.3.3.10
> >
> > of
> >
> > > > [RFC1812].
> > > >
> > > > > > > Does anybody actually use these
> >
> > ICMPv4
> >
> > > > messages?
> > > >
> > > > > I do
> > > > >
> > > > > > > recall Windows
> > > > > > > systems sending these messages
> >
> > when they are
> >
> > > > > bootstrapped,
> > > > >
> > > > > > > but...
> > > > > >
> > > > > >[suresh] If the WG believes any of these
> >
> > ought to
> >
> > > > be
> > > >
> > > > > obsoleted for
> > > > >
> > > > > >NAT devices, one option would be to
> >
> > dilute the
> >
> > > > > requirement to MAY
> > > > >
> > > > > >for NATs in this document. However, we
> >
> > need to
> >
> > > > provide
> > > >
> > > > > sufficient
> > > > >
> > > > > >justification for any deviation for NATs
> >
> > from RFC
> >
> > > > 1812.
> > > >
> > > > > While these messages are a "MUST"
> >
> > in
> >
> > > > RFC1812, my
> > > >
> > > > > take is that RFC1812
> > > > > is outdated in this respect, and that we
> >
> > should not
> >
> > > > > *require* them
> > > > > for NATs. I'm not saying we should
> >
> > obsolete these
> >
> > > > > messages here (it
> > > > > would be out of the scope of the document),
> >
> > but rather
> >
> > > > that
> > > >
> > > > > we should
> > > > > not require NATs to support these messages
> >
> > that nobody
> >
> > > > > (that I know
> > > > > of) is depending on.
> > > >
> > > > [suresh] Agreed. Do you suggest diluting both of
> >
> > the below
> >
> > > > MUSTs into MAY for NATs.
> > > >
> > > >           3. Parameter Problem Message,
> > > >           5. Router Advertisement and
> >
> > Solicitations
> >
> > > > > > > >        b. MAY support:
> > > > > > > >           1. Redirect
> >
> > Message, as
> >
> > > > described
> > > >
> > > > > in Section
> > > > >
> > > > > > > 4.3.3.2 of
> > > > > > >
> > > > > > > >              [RFC1812],
> > > > > > >
> > > > > > > If anything, I'd add that
> >
> > support should
> >
> > > > > default to
> > > > >
> > > > > > > "off".
> > > > > >
> > > > > >[suresh] RFC1812 already has MAY
> >
> > requirement on
> >
> > > > this
> > > >
> > > > > and doesnot
> > > > >
> > > > > >mandate this. RFC 1812 says:
> > > > >
> > > > > MAYs are less of a concern to me (as they
> >
> > give you the
> >
> > > > > option to
> > > > > support them, but do not require you to).
> > > >
> > > > [suresh] OK.
> > > >
> > > > > >    Contrary to [INTRO:2], a router MAY
> >
> > ignore
> >
> > > > ICMP
> > > >
> > > > > Redirects when
> > > > >
> > > > > >    choosing a path for a packet
> >
> > originated by the
> >
> > > > > router if the router
> > > > >
> > > > > >    is running a routing protocol or if
> >
> > forwarding
> >
> > > > is
> > > >
> > > > > enabled on the
> > > > >
> > > > > >    router and on the interface over
> >
> > which the
> >
> > > > packet
> > > >
> > > > > is being sent.
> > > > >
> > > > > My take here is that the spirit f RFC1812 is
> >
> > that you
> >
> > > > can
> > > >
> > > > > discard
> > > > > redirects *if* you are running a routing
> >
> > protocol
> >
> > > > (i.e.,
> > > >
> > > > > you're
> > > > > knowledgeable about routing). However, it
> >
> > would be
> >
> > > > insane
> > > >
> > > > > to honor
> > > > > redirects nowadays.... unless you're
> >
> > enforcing
> >
> > > > > something like GTSM
> > > > > (the TTL hack). If not, basically anybody
> >
> > could DoS
> >
> > > > you by
> > > >
> > > > > sending
> > > > > you a forged ICMP redirect.
> > > > >
> > > > > In anycase, as I said above, given that this
> >
> > is a MAY
> >
> > > > in
> > > >
> > > > > your
> > > > > document, no changes are needed (i.e., you
> >
> > are not
> >
> > > > > mandating support
> > > > > for redirects).
> > > >
> > > > [suresh] Right.
> > > >
> > > > > > > >           4. Address Mask
> >
> > Request/Reply
> >
> > > > > Message, as
> > > > >
> > > > > > > described in
> > > > > > >
> > > > > > > >              Section 7.4 of
> >
> > this
> >
> > > > document.
> > > >
> > > > > > > AFAIK, these messages are not used
> >
> > in
> >
> > > > practice
> > > >
> > > > > (even when a
> > > > >
> > > > > > > number of
> > > > > > > systems support them).
> >
> > Shouldn't they be
> >
> > > > > deprecated as
> > > > >
> > > > > > > with the
> > > > > > > information request/response?
> > > > > >
> > > > > >[suresh] I believe, It is not in the
> >
> > scope of this
> >
> > > > > document to
> > > > >
> > > > > >deprecate ICMP messages or their use
> >
> > outside of
> >
> > > > NATs.
> > > >
> > > > > >For this reason, the requirement for
> >
> > Address mask
> >
> > > > > request/Reply
> > > > >
> > > > > >support for NATs is diluted to MAY (from
> >
> > MUST in
> >
> > > > RFC
> > > >
> > > > > 1812).
> > > > >
> > > > > Same here. I have no real concerns here.
> > > >
> > > > [suresh] OK.
> > > >
> > > > Regards,
> > > > suresh
> > > >
> > > > > Kind regards,
> > > > >
> > > > > --
> > > > > Fernando Gont
> > > > > e-mail: [EMAIL PROTECTED] ||
> >
> > [EMAIL PROTECTED]
> >
> > > > > PGP Fingerprint: 7809 84F5 322E 45C7 F1C9
> >
> > 3945 96EE
> >
> > > > A9EF
> > > >
> > > > > D076 FFF1
> > > >
> > > > _______________________________________________
> > > > Behave mailing list
> > > > [EMAIL PROTECTED]
> > > > https://www.ietf.org/mailman/listinfo/behave
> > >
> > > _______________________________________________
> > > Int-area mailing list
> > > [email protected]
> > > https://www.ietf.org/mailman/listinfo/int-area
> >
> > --
> > --julien
> >
> > [ New email address: [EMAIL PROTECTED] ]



-- 
--julien

[ New email address: [EMAIL PROTECTED] ]
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