Anybody can participate in the IETF (Was: Why is IPv6 broken?)

Luigi Iannone luigi at net.t-labs.tu-berlin.de
Wed Jul 13 11:08:35 UTC 2011


On Jul 13, 2011, at 13:03 , Luigi Iannone wrote:

> Jeff,
> 
> on one point we agree, there is value in continuing this thread.

There is  _no_ value.....

my mistake...

Luigi


> I've tried to bring the discussion back to the technical issues, but I failed.
> 
> Personally, I find your emails aggressive and close to offensive in some sentences.
> Differently from you, in my replies (all of them public) I never judged your competences.
> 
> For me this thread is closed.
> 
> Have a nice day
> 
> Luigi
> 
> On Jul 13, 2011, at 11:21 , Jeff Wheeler wrote:
> 
>> Luigi, you have mis-understood quite a bit of the content of my
>> message.  I'm not sure if this is of any further interest to NANOG
>> readers, but as it is basically what seems to go on a lot, from my
>> observations of IETF list activity, I'll copy my reply to the list as
>> you have done.
>> 
>> On Wed, Jul 13, 2011 at 4:08 AM, Luigi Iannone
>> <luigi at net.t-labs.tu-berlin.de> wrote:
>>> Granted. You are the real world expert. Now can you stop repeating this in
>>> each email and move on?
>> 
>> No.  This is a point that needs to be not only made, but driven home.
>> You do not understand how routers work, which is why you are having
>> such difficulty understanding the severity of this problem.  The
>> lisp-threats work you have done is basically all control-plane /
>> signalling issues, and no data-plane issues.  This is not a
>> coincidence; it is because your knowledge of the control-plane side is
>> good and of the data-plane is weak.
>> 
>>> This is completely false. Several people gave credit to you about the
>>> existence of the threat you pointed out.
>> 
>> Really?  In April, when I posted a serious problem, and received no
>> replies?  Now, the original folks who I discussed this with, before
>> ever posting to the IETF LISP list, are finally seeking clarification,
>> because apparently there may have been some confusion in April,
>> possibly leading to their total dismissal of this as a practical
>> concern.
>> 
>>> This is again false. We had mail exchange both privately and on the
>>> mailinglist. We proposed to you text to be added to the threats draft but
>>> you did not like it. We are asking to propose text but we have no answer
>>> from you on this point.
>> 
>> Actually, you classified this as an implementation concern, which is
>> false.  You have said yourself that this is why you believe it
>> deserves just one sentence, if that, in the lisp-threats draft.  This
>> is not an implementation-specific concern, it is a design flaw in the
>> MS negative response scheme, which emerges to produce a trivial DoS
>> threat if LISP ever scales up.
>> 
>>>> Now there is a LISP "threats" draft which the working group mandates
>>>> they produce, discussing various security problems.  The current paper
>>>> is a laundry list of "what if" scenarios, like, what if a malicious
>>>> person could fill the LISP control-plane with garbage.  BGP has the
>>> 
>>> So you are saying that BGP can be victim of similar attacks/problem....
>>> still... if you are reading this email it means that the Internet is still
>>> running...
>> 
>> This is where I believe you are mis-reading my message.  Your threats
>> draft covers legitimate concerns which also exist in the current
>> system that is widely deployed, which is largely, BGP plus big FIB.
>> What you don't cover, at all, is an IMO critical new threat that
>> emerges in the data-plane from the design of the MS protocol.
>> 
>>> If you still think that LISP is using a flow-cache you should have a second
>>> read to the set of drafts.
>> 
>> This language may appear unclear if you haven't read it in the context
>> of my other postings.  LISP routing most certainly is a flow-cache,
>> however, the definition of "flow" is different.  Some platforms and
>> routing schemes see a flow as a layer-3 destination /32 or similar
>> (some 90s routers), others more granular (firewalls, where flows are
>> usually layer-4 and often stateful), and with LISP, the "flow" the
>> address space routed from your ITR to a remote ETR, which may cover a
>> large amount of address space and many smaller flows.
>> 
>> The LISP drafts also refer to these flows as "tunnels," but that
>> language could easily be confused to mean much more permanent, static
>> tunnels, or MPLS-like tunnels which are signaled throughout the
>> network of P routers.  So there are clear semantic issues of
>> importance when talking about LISP, and all these terms must be read
>> in the correct context.
>> 
>>> For the third time: this is false. We got the problem, we were asking for
>>> more specific information in order to quantify the risk. We asked you help
>> 
>> You haven't "got it," or you would already understand the risk very
>> well.  It is not my intention to fault you and your colleagues for
>> failing to understand this; but to demonstrate clearly that the right
>> kind of expertise is absolutely not being applied to LISP, and there
>> is a huge and possibly intractable threat that was completely
>> overlooked when producing what is meant to be an authoritative
>> document on currently-known "threats" to LISP.
>> 
>>> to state the problem and explained to you where the solution should be
>>> addressed. But you seem to be stuck on the operator vs. researcher
>>> discussion, which IMHO is just pointless.
>> 
>> Substantially all operators are "stuck" there.  They should participate more.
>> 
>>> Let me now ask a simple question: why are you so strongly against LISP?
>> 
>> No new work has been done to address the problem of scaling up the
>> number of locators or multi-homed end-sites.  However, the *claims*
>> being made by LISP advocates is that the caching scheme you have,
>> which is not novel, does solve this problem.  It does not.  It cannot
>> as there has been no novel work on this.
>> 
>> It is very unfortunate that LISP folks point to an academic paper that
>> studied the affect of 20k nominal flows.  This is not Internet-scale,
>> but a lot of you who are working hard on LISP don't seem to understand
>> that.  DoS attacks are a real world concern that we all have to live
>> with when deploying things for Internet use (as opposed to enterprise
>> VPN, etc.)  If you don't even consider their impact, how would you
>> expect content to be available over a LISP infrastructure?  How could
>> a large subscriber-access ITR platform work, if a trivial DoS against
>> it would impact all connected subscribers?
>> 
>> The root problem remains that as you scale up the number of locators
>> and destination prefixes, you need to scale up the hardware.  This is
>> made 10x worse, as I have demonstrated, by the inflexible and foolish
>> negative mapping reply scheme that is specified for LISP.
>> 
>>> You do not believe in it and do not see any value? Fine, other people do.
>> 
>> As I have said, I believe the value of LISP is limited to
>> VPN-over-Internet.  It can never scale up for large-scale, Internet
>> use.  This is an opinion shared by virtually all operators I've spoken
>> to who have followed LISP.  Why?  Again, pet project, ego, and
>> academia vs operational reality.
>> 
>> Get some other opinions.  I'm not the only guy who thinks this way,
>> I'm just the only one bothering to jump up and down, because I think
>> LISP is a really good example of what is being discussed in this NANOG
>> thread (IETF brokenness due to lack of operator participation), and a
>> waste of vendor resources.
>> 
>>> You think that there are issues that cannot be solved? Fine, other people
>>> believe those issues can be solved and are scratching their head to find
>>> deployable solutions.
>> 
>> I've seen the "LISP Youtube Video."  It looks clever, but it'll never,
>> ever work at large scale.  Would you like to know what actually does
>> work, has existing code, and just needs some killer app?  SCTP.  It
>> does the mobility that LISP promises, and removes the need to even
>> have loc/ID separation, because applications perceive a socket which
>> the OS (SCTP stack) at each end can multi-home, and port across
>> changing IP addresses, and so on.
>> 
>> SCTP isn't going to sell any routers, but it solves all those problems
>> that LISP would like to solve (but can't at scale.)
>> 
>> -- 
>> Jeff S Wheeler <jsw at inconcepts.biz>
>> Sr Network Operator  /  Innovative Network Concepts
> 
> 





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