Subject: [mpls-tp] MPLS-TP OAM framework - editorial comments

From: "Rolf Winter" <[email-masked]>
Date: Wed, 28 Apr 2010 14:21:30 +0200

Hi,

Some editorial comments to the draft. More technical comments will follow in a separate Email.

General comments:
I think some of the references are wrong. E.g. page 12. " Path segment tunnels (PSTs), as defined in [5], are". [5] points to the requirements which does not define the PST.

There is a HUGE amount of repetition in the text. Reads like a Mantra at times. E.g. page 14, in two paragraphs you explain what performance degradation could mean, twice the same thing. Even worse in section 4 where in every subsection you repeat that the OAM packets need to fate share while you already have mentioned that for the generic case.

You might want to define 'adaptation function' at the top or reference it properly (some other terms might benefit from references too, e.g. the "uniform model of TC code point copying").

Smaller comments:
Section 2.2, page 7: s/loopback: it is an/loopback: an/ Section 2.2: Capitalize constistently after the ':'
Section 3.1: You write at the beginning "Maintenance Entities are a relationship", sounds odd to be, maybe "Maintenance Entities define a relationship" or "are characterized by the relationship"...
Page 13: s/MPLS-TP section/MPLS-TE Section/ (to be consistent) Page 13, Section 3.3 first paragraph: s/Regarding MPLS-TP PW/Regarding MPLS-TP PWs/; s/In the context of MPLS-TP Section/ In the context of a MPLS-TP Section/ Page 13: "The MEG the OAM packet belongs to is inferred from the MPLS or PW label or, in case of MPLS-TP section, the MPLS-TP port the OAM packet has been received with the GAL at the top of the label stack." (This does not parse for me, I would add an 'a' before MPLS-TP Section and I think you might want to add an 'an' between 'with' and 'the GAL') Page 14: " Each OAM solution will further detail its applicability as a pro-active or on-demand measurement" I don't think 'measurement' is quite the right word here but 'mechanism' or similar. 
Section 3.6.: The paragraph starting with "Local policy...". Remove the "...triggering the request." Part at the end as is starts to repeat itself and makes the sentence hard to parse. Same paragraph s/irrespectively on/irrespective of/. Same section, remove the '(e.g. PST)', it seems redundant at best. s/Sometimes PST/ Sometimes a PST/ Section 3.7, page 19:  Isn't the part about: "The source MEP should also include Target MIP information in the OAM packet to allow proper identification of the node and the MIP the OAM packet is addressed to." identical with the previous sentence in terms of what needs to be in the OAM packet. I cannot see the difference easily.
Page 19: You say "Better mechanisms" I'd say "Other mechanisms" or explain why you specify something that is "bad".
Page 19: s/exhaust/exhaustion/
Page 23: s/LPSTMEE/LPSTME/
Page 26: s/ These techniques share in common the characteristic that/ These techniques share the characteristic that Page 27: Point 5. I do not think this is an implication, is it? Somehow doesn't fit the list.
Page 28: "In order to perform pro-active Connectivity Verification function" either leave out the 'function' or add an article. Same in the following sentence.
Page 28: s/MPLS TP is deployed in IP-based environment/MPLS TP is deployed in IP-based environment/ Page 33: s/CC-V defect entry criteria resolves is longer/CC-V defect entry criteria is reached later/ Page 33: I thought there is no plural of 'information'. I'd anyway rather use 'parameters' here.
Page 33: Last sentence in 5.1.3: Either remove 'some' or specify which.
Page 34: last paragraph s/however in transport network/however in a transport network/; s/the alarm associate/the alarm associated/; s/ to NMS/ to a NMS/; remove 'these' from 'all these secondary'
Page 36: "transactionally correlated" sounds strange to me, why not just use 'correlated' as you in the On demand section later Section 5.5.1: You have the exact same text already in section 5.5. I'd suggest to remove it in 5.5.
Page 39: the term 'craftsperson' sounds strange to me, more like a plumber or something. Would 'maintenance personnel' be a better fit, or just 'initiated manually'? Same paragraph s/that that/than/ Page 41: s/ correlated evaluate/ correlated to evaluate/ Page 43: first paragraph change to "For a one way test, the remote MEP sink receives the OAM test packets and calculates the packet loss. For a two way test"
Section 6.3.1.1. s/NMS/a NMS/ same in section 7.1.1 Page 43: s/throught/throughput/; also delete everything after 'provisioning'
Page 44: Route tracing, first paragraph: remove the 'it' at the end of the paragraph Page 46: s/into a locked and notify/into a locked state and notifies/ Section 7.1.2 multiple times s/notify/notifies/ Search/replace 'out of band' with 'out-of-band'; 'on demand' 'on-demand'; more hyphens missing is 'fault free', 'layer originated' 'man in the middle' and others.

Hope these are helpful.

Best,
	Rolf

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