Re: [secdir] [Detnet] Secdir last call review of draft-ietf-detnet-mpls-05

> On 13 Mar 2020, at 01:35, Watson Ladd <watsonbladd@gmail.com> wrote:
> 
> On Thu, Mar 12, 2020 at 4:07 AM Lou Berger <lberger@labn.net> wrote:
>> 
>> Watson,
>> 
>> Can you provide context here? Can you be explicit on what you see needs to
>> be addressed (beyond what is in this document as well as related rfcs)?
> 
> You have to talk about how the layers interact, and can't just say the
> lower level handles anything without any guide as to what needs to be
> provided by that lower layer.
> 
> I think my concerns about the assumptions this could be fixed by
> saying. "All nodes are trusted and any of them can misbehave in ways
> that affect the network.  

That is a fundamental assumption of all routers, so there really is no need to state it.

As I said earlier, a practical solution to the byzantine routing problem was proposed by Radia about 30 years ago and there is zero interest in it because the trust assumption is fundamentally ingrained in the routing architecture, and so far it has been well founded.

> If the MPLS layer cannot provide sufficient
> determinism, then the DetNet mechanisms won't work".  

That is kind of fundamental to the point where I am also not sure it needs to be stated, and if it does need to be stated then it needs to go up the tree in one of the fundamental documents, not each of the data-plane documents (there are quite a few such documents).

> I agree we
> shoudn't require an entire massive security framework to be quoted
> again here, but there must be some details of this embedding that are
> worth noting, and yet I don't see them called out in the security
> considerations section.

Is this about showing that we have done something to prove that we take security seriously, or is it about giving practical advice to someone deploying the technology. Hopefully the later, in which case I think this is well covered by the DetNet context and the MPLS documents, all of which the reader can be assumed to be familiar with.

> 
> Are there really no specific concerns about the interaction between
> DetNet and MPLS?

There are MPLS service requirements and expectations. However I don’t think there is an interaction per se.

It is as I already said about pseudowires. If the performance of this approach is not good enough, then spend the money and buy a dedicated physical network.

- Stewart

> 
>> 
>> Thank you,
>> Lou
>> 
>> 
>> ----------
>> On March 11, 2020 10:30:27 PM Watson Ladd <watsonbladd@gmail.com> wrote:
>> 
>>> I don't see any reason why RFC 3552's guidelines shoudn't apply to this draft.
>>> 
>>> If there is a MPLS exception I'd like to see the rules that should be applied.
>>> 
>>> As is I don't see any reason why the assumptions can't be explicitly
>>> spelled out, either in the Security Considerations or elsewhere.
>>> 
>>> _______________________________________________
>>> detnet mailing list
>>> detnet@ietf.org
>>> https://www.ietf.org/mailman/listinfo/detnet
>>> 
>> 
>> 
> 
> 
> -- 
> "Man is born free, but everywhere he is in chains".
> --Rousseau.