[bess] Benoit Claise's Discuss on draft-ietf-bess-mvpn-extranet-04: (with DISCUSS and COMMENT)

["Benoit Claise" <[e-mail]>]

Benoit Claise has entered the following ballot position for
draft-ietf-bess-mvpn-extranet-04: Discuss

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DISCUSS:
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As mentioned in Sue Hares' OPS DIR, 3 major concerns. The last one is
actually for the security ADs.

Status: Not ready,  three major concerns and two editorial nits:  

Major concerns:

1)      Specification of the Extranet Source Extended Community and Extra
Source extended Community

Please provide the type of detail as show in RFC 4360 sections 3.1, 3.2,
and 3.3.  

2)      Why is there no Deployment considerations section? 

The whole draft is a set of rules for handling policy, BGP A-D routes,
tunnel set-up, and PIM Join/leaves in the case of an intra net.  Unless
these rules are followed exactly, traffic may flow into a VPN it is not
suppose to.

If the customer and the SP must coordinate on setting up filters, the
procedure is outside the document.

An error in any of these set-ups is considered a “security violation”. 

Milo Medin stated “with enough trust” a rock can fly to the moon. 
However, the NASA flights were fragile and risky.  In the journey to the
moon, there was no other choice.  Instrumentation has 4-5 backups.

In this set-up, one has to ask “is there another choice” to this whole
design that seem fragile addition of extranets to an intra-AS multicast
design.  If the design is not fragile, then there should be a deployment
section indicating how to manage the RTs, RDs, and policy set-up. 
Perhaps experience with the Intra-As has shown deployment tips that would
make this less fragile.  If so,  it would be good to include an
operations consideration section.

If a new class of tools provides monitoring or provisioning, mentioning
these would be useful.  If yang modules are being developed, that would
be useful.

Places that indicate issues with violated constraint:

p. 11, 12, 19 (2.3.2 – a priori knowledge, inability to detect), , p. 25
last paragraph (violation of constraints will cause things to not work. 
However, only policy can control), p. 27 4.2.2 (1st paragraph, Route
Reflector must not change), p. 31 (5.1, first paragraph),

3)      Is security section really a security section? It seems more like
“do this policy” or this will fail.  It should get a stronger review from
the security directorate


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COMMENT:
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Editorial suggestions:

 

Summary: In general the authors provide dense English text to describe
this rules.   In general the English text contains valid complex
sentences.  However, a few things should be suggested:

 

1)      PTA – define it in a definition section or spell out the
abbreviation

2)      Phrases like  “the RT RT-R” become overly dense.  Use “Route
Target RT-R”.

3)      Breaking up section 6.2.1 – with subjection and subtitles would
make it more readable,

4)      P. 36 second paragraph.  The reason for the “MUST” in 1st full
paragraph is a bit vague.  It seems logical, but the reasoning is just
vague in the text.

5)      paragraph 2 in page 47 (section 7.3.1) is awkward, please reword.


6)      Paragraph 5 in page 47 (section 7.3.1) – does not explain why the
condition should hold.  The authors have done this in eac other case, so
it seems inconsistent.

7)      Page 53 – section 7.4.5 paragraph 3  “VRF route Import EC” –
please spell out first usage and give abbreviation (VRF Route Import
Extended Community (EC).