Re: [PCN] I-D Action: draft-ietf-pcn-sm-edge-behaviour-11.txt

[Tom Taylor <[e-mail]>]

Changes listed below were as agreed at the meeting (use 3-in-1 rather 
than RFC5696, recognize possible use of MPLS, correct error). I found a 
few additional points that also needed fixing, as noted below.

Section 1, description of experiment, bullets
---------------------------------------------
Changed "CL" to "SM" (cut-and-paste error).

Section 1.1, codepoint terminology
----------------------------------
Changed reference and terminology to 3-in-1.

Section 2 second bullet
-----------------------

OLD

  o excess-traffic-marking of PCN-packets uses the PCN-Marked (PM) 
codepoint defined in [RFC5696];

NEW

  o for IP transport, excess-traffic-marking of PCN-packets uses the 
excess-traffic-marked (ETM) codepoint defined in [ID.pcn-3-in-1]; for 
MPLS transport, an equivalent marking is used as discussed in 
[ID.pcn-3-in-1] Appendix C;	

Section 2 last bullet
---------------------

OLD

  o the set of valid codepoint transitions is as shown in Section 4.2 
of [RFC5696].		

NEW

  o the set of valid codepoint transitions is as shown in Sections 5.2.1 
and 5.2.3.1 of [ID.pcn-3-in-1].	

Section 3.2.1, definition of ETM-rate
-------------------------------------
Changed "PM codepoint" to "ETM codepoint".

Section 3.3, second sentence
----------------------------
Restored the "Decision Points MUST implement both" as agreed at the meeting.

Section 3.3.2, end
------------------
Added the following to tie things together:

    The Decision Point SHOULD log each round of termination as described	
    in Section 5.2.1.2.
	
Section 3.3.3, action on missing response from ingress node
-----------------------------------------------------------
(Identified error) Deleted the workaround procedure, which was suitable 
only for CL. Text now reads:

[SM-specific] If the second request to the PCN-ingress-node also fails, 
the Decision Point SHOULD notify management. The log format defined in 
Section 5.2.1.1 is also suitable for this case.

Section 3.5, action on expiry of t_meas
---------------------------------------
Deleted CL-specific text (cut-and-paste error).

Section 4.2.1
-------------
Replaced first two paragraphs with reference to relevant section of 3-in-1.

Section 4.2.2
-------------
Changed reference from RFC5696 to 3-in-1.

Section 4.6
-----------
Changed "MAY" to "may" for example uses.

Section 4.7
-----------
Replaced existing text.

OLD

The PCN CL per-domain behaviour could theoretically interfere with the 
use of end-to-end ECN due to reuse of ECN bits for PCN marking.		
However, this is not a problem in practice because of the need to tunnel 
PCN-packets from ingress to egress (see Section 5.1.2). The encapsulated 
header can retain the original ECN markings as received at the 
PCN-ingress-node, leaving the ECN bits in the encapsulating header fully 
available for use by PCN.

NEW

    The PCN SM per-domain behaviour could theoretically interfere with
    the use of end-to-end ECN due to reuse of ECN bits for PCN marking.
    Section 5.1 of [ID.pcn-3-in-1] describes the actions that can be
    taken to protect ECN signalling.  Appendix B of that document
    provides further discussion of how ECN and PCN can co-exist.

Section 5.1.1 second bullet
---------------------------
Changed reference to 3-in-1 Appendix A.

Section 5.1.2, second paragraph, last sentence
----------------------------------------------

OLD

Since all PCN packets will be tunneled, the PCN-ingress-node also needs 
to know the address of the peer PCN-egress-node associated with each filter.

NEW

The PCN-ingress-node also needs to know the address of the next-hop 
PCN-node associated with each filter.

*Comment*: I think I should have added: "If tunneling is used, the 
next-hop PCN-node will be the peer PCN-egress-node."

*Further comment*: how should this read for MPLS?

Section 5.1.2, fourth paragraph, saecond sentence
-------------------------------------------------
Added "If tunneling is used ...", so the sentence now reads:

If tunneling is used, these filters are
    constructed on the basis of the identifier of the tunnel from which
    the incoming packet has emerged (e.g. the source address in the outer
    header if IP encapsulation is used).

Section 5.1.3, first paragraph, last sentence
---------------------------------------------
Revised to drop CL-specific stuff and correct misleading text. New text 
reads:

    "Finally, a new object may need to be defined at the PCN-
    interior-nodes to represent the packet-size-independent excess-
    traffic-marking metering algorithm."

Section 5.2.1.1, second paragraph
---------------------------------
Added "PCN-ingress-node or ..." to make it clear the log could be used 
for missing reports at both ingress and egress.

Section 5.2.1.2, description of "TermRate" parameter
----------------------------------------------------
Units changed from millions of octets per second to thousands of octets 
per second -- seemed more reasonable on reflection.

Normative References
--------------------
Deleted RFC5696, added 3-in-1.

Authors
-------
Restored Joy Zhang's missing E-mail address.