Jeff, on one point we agree, there is value in continuing this thread. 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 > <[email protected]> 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 <[email protected]> > Sr Network Operator / Innovative Network Concepts
