Hi Acee,

Indeed the mechanism for key rollover is well documented and widely implemented 
via configuration/provisioning methods.

My question was regarding how the specific steps/procedures as described in 
https://datatracker.ietf.org/doc/html/rfc8177#section-2.2 are going to get 
realized in this proposal where we have an IGP and PCEP protocols in operation.

To me the use of this mechanism in such dynamic and distributed routing 
protocol operations seems to be under-specified for a standards track document 
– not good enough for ensuring interoperable implementations.

Hope that clarifies and I’ll rest my case with that.

Thanks,
Ketan

From: Acee Lindem (acee) <acee=40cisco....@dmarc.ietf.org>
Sent: 23 July 2021 22:24
To: Ketan Talaulikar (ketant) <ket...@cisco.com>; l...@ietf.org
Cc: draft-ietf-lsr-pce-discovery-security-supp...@ietf.org; pce@ietf.org
Subject: Re: WG Last Call for IGP extension for PCEP security capability 
support in the PCE discovery - draft-ietf-lsr-pce-discovery-security-support-05

Hi Ketan,

From: "Ketan Talaulikar (ketant)" 
<ketant=40cisco....@dmarc.ietf.org<mailto:ketant=40cisco....@dmarc.ietf.org>>
Date: Friday, July 23, 2021 at 11:20 AM
To: Acee Lindem <a...@cisco.com<mailto:a...@cisco.com>>, 
"l...@ietf.org<mailto:l...@ietf.org>" <l...@ietf.org<mailto:l...@ietf.org>>
Cc: 
"draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>"
 
<draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>>,
 "pce@ietf.org<mailto:pce@ietf.org>" <pce@ietf.org<mailto:pce@ietf.org>>
Subject: RE: WG Last Call for IGP extension for PCEP security capability 
support in the PCE discovery - draft-ietf-lsr-pce-discovery-security-support-05

Hi Acee,

Agree about the keychain provisioning part.

The distribution via IGP for the key selections and the handling  of the same 
in PCEP sounded new to me. Is there any precedent for this? How does it all 
work actually and what is needed on the PCE and PCC to handle the 
change/transitions – this is all missing – probably needs a PCEP spec? This is 
many PCCs trying to connect to a PCE. I was trying to understand this better 
and how all that weighs against a potential for attack/disruption by someone 
doing a M-i-M or replay attack.

Roll-over of keys with key-chains is well-understood.

https://datatracker.ietf.org/doc/html/rfc8177#section-2.2

As is TCP-AO and TLS authentication. The only further specification required 
would the configuration in the PCE YANG model(s).

Thanks,
Acee

Just some questions … as this seemed something new to me and the spec does not 
provide any pointers.

Thanks,
Ketan

From: Acee Lindem (acee) 
<acee=40cisco....@dmarc.ietf.org<mailto:acee=40cisco....@dmarc.ietf.org>>
Sent: 23 July 2021 18:52
To: Ketan Talaulikar (ketant) <ket...@cisco.com<mailto:ket...@cisco.com>>; 
l...@ietf.org<mailto:l...@ietf.org>
Cc: 
draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>;
 pce@ietf.org<mailto:pce@ietf.org>
Subject: Re: WG Last Call for IGP extension for PCEP security capability 
support in the PCE discovery - draft-ietf-lsr-pce-discovery-security-support-05

Hi Ketan,

From: "Ketan Talaulikar (ketant)" 
<ketant=40cisco....@dmarc.ietf.org<mailto:ketant=40cisco....@dmarc.ietf.org>>
Date: Friday, July 23, 2021 at 9:10 AM
To: Acee Lindem <a...@cisco.com<mailto:a...@cisco.com>>, 
"l...@ietf.org<mailto:l...@ietf.org>" <l...@ietf.org<mailto:l...@ietf.org>>
Cc: 
"draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>"
 
<draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>>,
 "pce@ietf.org<mailto:pce@ietf.org>" <pce@ietf.org<mailto:pce@ietf.org>>
Subject: RE: WG Last Call for IGP extension for PCEP security capability 
support in the PCE discovery - draft-ietf-lsr-pce-discovery-security-support-05

Hello All,

I have reviewed this draft and have the following comments for the authors to 
address and the WG to consider:


1)     Is there any precedent for the advertisement of auth keychain info 
(ID/name) in such a manner that is flooded across the IGP domain? When the 
actual keychain anyway needs to be configured on all PCCs what is really the 
value in their advertisement other than possibly exposure to attack? I hope the 
security directorate reviewer looks at this closely and we get some early 
feedback specifically on this aspect.

The key-chain mechanism was standardized in RFC 8177 and is referenced by all 
the routing protocol YANG models. While key-chains, as well as, pre-shared keys 
need to be configured, having multiple configured key-chains that are 
selectable via discovery is obviously more operationally secure than having a 
single one.

Thanks,
Acee


2)     In sec 3.2 and 3.3, new sub-TLVs are being introduced. Their ASCII art 
pictures represent the OSPF TLVs. The ISIS TLV structure is different. While 
this will be obvious to most in this WG, I would request this to be clarified – 
perhaps by introducing separate diagrams for both protocols or skipping the art 
altogether.

3)     RFC5088 applies to both OSPFv2 and OSPFv3. This is however not clear in 
the text of this document.

4)     Looks like RFC5088 asked for the PCE Capabilities Flags registry to be 
created as a top-level IANA OSPF registry - 
https://datatracker.ietf.org/doc/html/rfc5088#section-7.2 – so it should have 
been placed here : 
https://www.iana.org/assignments/ospf-parameters/ospf-parameters.xhtml. What 
seems to have happened is that it got created under OSPFv2 which is wrong - 
https://www.iana.org/assignments/ospfv2-parameters/ospfv2-parameters.xml#ospfv2-parameters-14.
 Since this draft updates RFC5088, it is necessary for this document to fix 
this error. I would support Les in that perhaps all of this (i.e. everything 
under/related to PCED TLV) ought to be moved under the IANA Common IGP registry 
here : https://www.iana.org/assignments/igp-parameters/igp-parameters.xhtml

5)     The document needs to be more specific and clear about which IANA 
registries to be used to avoid errors that have happened in the past (see (3) 
above).

6)     Appendix A, I believe what the authors intended here was that whether to 
use MD5 auth or not was part of discovery but static configuration on the PCE 
and PCC? The keychain introduced in this document can also be used along with 
MD5. Honestly, I don’t see a strong reason to not include MD5 in the signalling 
except that it is deprecated (even if widely deployed). This document would not 
conflict or contradict with RFC5440 if it did include a bit for MD5 support as 
well. As  follow-on, perhaps this document should also update RFC5440 – 
specifically for the security section? I see RFC8253 introducing TLS that 
updates RFC5440 but nothing that introduces TCP-AO?. In any case, these are 
aspects for PCE WG so I will leave those to the experts there.

Thanks,
Ketan

From: Lsr <lsr-boun...@ietf.org<mailto:lsr-boun...@ietf.org>> On Behalf Of Acee 
Lindem (acee)
Sent: 21 July 2021 22:16
To: l...@ietf.org<mailto:l...@ietf.org>
Cc: 
draft-ietf-lsr-pce-discovery-security-supp...@ietf.org<mailto:draft-ietf-lsr-pce-discovery-security-supp...@ietf.org>
Subject: [Lsr] WG Last Call for IGP extension for PCEP security capability 
support in the PCE discovery - draft-ietf-lsr-pce-discovery-security-support-05

This begins a 3-week WG Last Call, ending on August 4th, 2021, for 
draft-ietf-lsr-pce-discovery-security-support. Please indicate your support or 
objection to this list before the end of the WG last call. The longer WG last 
call is to account for IETF week.

  
https://datatracker.ietf.org/doc/draft-ietf-lsr-pce-discovery-security-support/


Thanks,
Acee


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