Subject: [P2PSIP] Spencer Dawkins' Yes on draft-ietf-p2psip-sip-19: (with COMMENT)

From: "Spencer Dawkins" <[email-masked]>
Date: Tue, 19 Apr 2016 07:03:14 -0700

Spencer Dawkins has entered the following ballot position for
draft-ietf-p2psip-sip-19: Yes

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COMMENT:
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This was a bit confusing to me.

   AOR domain not supported by overlay?  If the domain part of the AOR
      is not supported in the current overlay, the user SHOULD query the
      DNS (or other discovery services at hand) to search for an
      alternative overlay that services the AOR under request.
      Alternatively, standard SIP procedures for contacting the callee
      SHOULD be used.
      
If you don't query the DNS (or other discovery services), and you don't
use standard SIP procedures, are there any other choices? With both of
these being SHOULDs, a conformant implementation might not do either of
them. Is that expected?

If you need this to be RFC 2119 language, I'm guessing this would be
"MUST either do X or Y", but I'm not sure it needs to be RFC 2119.

If you really do need two alternative SHOULDs, it's not required to
explain why a SHOULD is not a MUST, but since the goal is that an
implementer is making an informed choice, helping the implementer
understand why one might not want to do what one SHOULD do is usually
helpful.

I think that 

   A callee MAY choose to listen on both
   SIP and SIPS ports and accept calls from either SIP schemes, or
   select a single one. 
   
is using "SIP schemes" generically, but this might be clearer if you just
said "either scheme".

I'm not on top of SIPS these days, but I didn't think

   SIPS requires end-to-end protection that may include client links and
   endpoint certificates.
   
was "end-to-end protection". Is it? I thought that it was
protected-hop-by-protected-hop. Or maybe you only mean SIPS in P2PSIP? 

Sorry if I'm confused (and the SIP Forum will be thrilled to hear this,
if I'm just confused).

I can figure out what "fork explosion" and "fork bomb" are, but are these
terms in common usage in the SIP community? Is there a definition or
reference for them?