RE: [tcpm] tcpsecure: how strong to recommend?

"Anantha Ramaiah \(ananth\)" <> Sat, 29 September 2007 04:44 UTC

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Subject: RE: [tcpm] tcpsecure: how strong to recommend?
Date: Fri, 28 Sep 2007 21:44:01 -0700
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From: "Anantha Ramaiah \(ananth\)" <>
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> (FWIW, I still don't get it.  If SHOULD gives the leeway not 
> to do something for whatever reason you can come up with then 
> how is it really different from MAY?  I don't know .... I 
> think there might be a distinction in your head, but I can't 
> understand it.)

Ok, I can try a brain dump :-)

Per RFC 2119

Should is defined as :

3. SHOULD   This word, or the adjective "RECOMMENDED", mean that there
   may exist valid reasons in particular circumstances to ignore a
   particular item, but the full implications must be understood and
   carefully weighed before choosing a different course.

So, the mitigations suggested in TCP secure is RECOMMENDED to have, but
valid reasons like the ones which I pointed out may exist which can
preclude it's implementation in a particular stack. Also implications of
not adopting TCP secure is well understood since one may chose to "live"
with less robustness. Also the general feeling is that post 9/11
security has increasingly becoming important in all walks of life,
increasing robustness of a widely used protocol like TCP is not a bad
idea, so making these mitigations a SHOULD is not a big deal, IMO.

MAY is defined as :

5. MAY   This word, or the adjective "OPTIONAL", mean that an item is
   truly optional.  One vendor may choose to include the item because a
   particular marketplace requires it or because the vendor feels that
   it enhances the product while another vendor may omit the same item.

Well if we view TCP secure as a optional thing, yes it makes sense to
use MAY. I think TCP secure falls in a category above "optional" and
below MUST and hence a SHOULD.

Well, this is my thinking and I am not opposed to other's thinking, but
saying that "SHOULD doesn't give leeway not to do something", is
something which I would want to dis-agree.

Hope I am clear. Again this is purely my opinion.


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