The text looks good. I would just suggest on editorial change, substitute 
“Let’s consider” with “Consider”.

Thanks,
Dino

> On Sep 20, 2017, at 11:12 PM, Fabio Maino <[email protected]> wrote:
> 
> Hi Dino, 
> thanks for the comments. 
> 
> Here is the edited text:
> 
> 
> 
>> 6. Replay Attacks
>> 
>> Replay attacks against LISP-SEC can be mounted by either (1) re-sending a 
>> valid Map-Reply to the ITR, or (2) re-sending a valid Map-Request to the 
>> Map-Resolver, Map-Server, or ETR.
>> 
>> In order to understand LISP-SEC protection from replay attacks it's 
>> important to note that an ITR, upon receiving a valid Map-Reply, MUST 
>> discard the <nonce,ITR-OTK> pair stored at the ITR that corresponds to the 
>> nonce in the received valid Map-Reply. 
>> 
>> Let's consider first the case when the replay attack is mounted replaying a 
>> Map-Reply. The ITR, upon receiving the replayed Map-Reply, will try to match 
>> the Map-Reply's nonce with the list of stored <nonce,ITR-OTK> pairs. Since 
>> the <nonce,ITR-OTK> pair was removed when the valid Map-Reply arrived at the 
>> ITR, the replayed Map-Reply will be discarded defeating the replay attack. 
>> 
>> Let's consider now the case when the replay attack is mounted replaying a 
>> Map-Request message to either a Map-Resolver, a Map-Server, or an ETR. The 
>> replayed Map-Request message will be processed as any other Map-Request 
>> message by the Map-Resolver, Map-Server, and ETR, and will generate a 
>> replayed Map-Reply that eventually reaches the ITR. However, the ITR upon 
>> receiving the replayed Map-Reply, will try to match the Map-Reply's nonce 
>> with the list of stored <nonce,ITR-OTK> pairs. Since the <nonce,ITR-OTK> 
>> pair was removed when the valid Map-Reply arrived at the ITR, the replayed 
>> Map-Reply will be discarded defeating the replay attack.
> 
> Please also note that point (3) is not really an issue, as a valid message 
> and a replayed message are indistinguishable by definition. Whichever arrives 
> first is the valid message, and all the subsequent ones are replay attacks.
> 
> Fabio
> 
> 
> On 9/20/17 12:08 PM, Dino Farinacci wrote:
>> I have a comment on this newly added paragraph:
>> 
>> <PastedGraphic-72.png>
>> 
>> I don’t think it reads clearly. Here are my comments:
>> 
>> (1) First sentence, I think you mean “replay it” versus “reply it”.
>> 
>> (2) You should talk separately of a replayed Map-Request and then a replayed 
>> Map-Reply. Combining it makes it confusing on which case the ITR discards a 
>> Map-Reply. Because a Map-Reply is not responded to by a replayed Map-Reply 
>> so it can only mean a replayed Map-Reqeust.
>> 
>> (3) And if the replayed Map-Reply returns to the ITR BEFORE the one from the 
>> non-attacker, it cannot tell if the Map-Reply was from a non-attacker or an 
>> attacker. So you need to explain what happens in both cases (where the 
>> simple case is already in the text above).
>> 
>> (4) What is a “LISP-SEC computation”? That needs to be made more clear.
>> 
>> Please clarify this section. It needs it.
>> 
>> Dino
>> 
>> 
>>> On Sep 20, 2017, at 10:54 AM, The IESG <[email protected]> wrote:
>>> 
>>> 
>>> The IESG has received a request from the Locator/ID Separation Protocol WG
>>> (lisp) to consider the following document: - 'LISP-Security (LISP-SEC)'
>>>  <draft-ietf-lisp-sec-13.txt> as Experimental RFC
>>> 
>>> The IESG plans to make a decision in the next few weeks, and solicits final
>>> comments on this action. Please send substantive comments to the
>>> [email protected] mailing lists by 2017-10-04. Exceptionally, comments may be
>>> sent to [email protected] instead. In either case, please retain the beginning 
>>> of
>>> the Subject line to allow automated sorting.
>>> 
>>> Abstract
>>> 
>>> 
>>>   This memo specifies LISP-SEC, a set of security mechanisms that
>>>   provides origin authentication, integrity and anti-replay protection
>>>   to LISP's EID-to-RLOC mapping data conveyed via mapping lookup
>>>   process.  LISP-SEC also enables verification of authorization on EID-
>>>   prefix claims in Map-Reply messages.
>>> 
>>> 
>>> 
>>> 
>>> 
>>> The file can be obtained via
>>> https://datatracker.ietf.org/doc/draft-ietf-lisp-sec/
>>> 
>>> IESG discussion can be tracked via
>>> https://datatracker.ietf.org/doc/draft-ietf-lisp-sec/ballot/
>>> 
>>> 
>>> No IPR declarations have been submitted directly on this I-D.
>>> 
>>> 
>>> 
>>> 
>>> _______________________________________________
>>> lisp mailing list
>>> [email protected]
>>> https://www.ietf.org/mailman/listinfo/lisp
>> 
> 

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