Path Computation Element Communication Protocol (PCEP) Extensions for MPLS-TE Label Switched Path (LSP) Auto-Bandwidth Adjustment with Stateful PCE
Note: This ballot was opened for revision 11 and is now closed.
Deborah Brungard Yes
Alissa Cooper No Objection
Roman Danyliw No Objection
Comment (2019-09-18 for -11)
** I support Ben Kaduk’s DISCUSS position on the need for clarity in the definition of Overflow-Count and Overflow-Threshold ** Section 5.2.x. Error handling: -- A number of the sub-TLVs define ranges smaller than would be possible given the number of bit (e.g., 1..604800 in a 32-bit field; 1.100), how would an error be signaled for values used outside that range? -- For values that are [IEEE.754.1985]), how should negative value be processed? ** Nits: -- Section 1. Typo. s/a Active stateful/an Active stateful/ -- Section 184.108.40.206. For consistency with the other sections s/1 to 604800/1 to 604800 (7 days)/ -- Section 6.6. Typo. s/signalling/signaling/
Benjamin Kaduk (was Discuss) No Objection
Thanks you for addressing my Discuss (and Comment) points!
(Suresh Krishnan) No Objection
(Mirja Kühlewind) No Objection
Comment (2019-09-09 for -11)
Thanks for quickly addressing the TSV-ART review (and thanks to David for this very clear and well explained review)! I would have preferred to actually see a normative requirement as original proposed by David ("sample interval SHOULD NOT be less than 1 minute") in section 5.2.1. Also I would have expected the proposed new text to show up somewhere in section 4 (maybe even as a new subsection).
Barry Leiba (was Discuss) No Objection
Comment (2019-09-16 for -11)
[Updates have been made; thanks, everyone, for the discussion and for considering my comments.] Thanks for another clear document. There are some "SHOULD" key words in one section that I would like to discuss, and that I think we ought to be able to resolve without much difficulty: — Section 5.7 — There are various “SHOULD”s in this section, and I have the same comment about all of them: BCP 14 says, about “SHOULD”, 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.” I see no guidance here to help the reader understand what such circumstances and implications are, so I can’t see how an implementer can evaluate the situation. Can you provide any help here? And these below are purely editorial comments, which need no detailed response; please just consider them. — Section 1 — Over time, based on the varying traffic pattern, an LSP established with a certain bandwidth may require to adjust the bandwidth reserved in the network dynamically. “may require adjustment of the bandwidth” This is similar to the Passive stateful PCE model, while the Passive stateful PCE uses path request/reply mechanism, the Active stateful PCE uses report/update mechanism. NEW This is similar to the Passive stateful PCE model: while the Passive stateful PCE uses a path request/reply mechanism, the Active stateful PCE uses a report/update mechanism. END This document defines the PCEP extensions needed to support Auto- Bandwidth feature in a Active stateful PCE model NEW This document defines the PCEP extensions needed to support an Auto- Bandwidth feature in an Active stateful PCE model END — Section 2.3 — This value indicates how many times consecutively, the percentage or absolute difference Add a comma after “times”. — Section 3 — The PCEP speaker supporting this document must have a mechanism “A PCEP speaker”. o It is required to identify and inform the PCC, which LSPs are enabled with Auto-Bandwidth feature. Not all LSPs in some deployments would like their bandwidth to be dependent on the real-time bandwidth usage but be constant as set by the operator. NEW o It is necessary to identify and inform the PCC which LSPs have the Auto-Bandwidth feature enabled. In some deployments, not all LSPs would like their bandwidth to be dependent on the real-time bandwidth usage, but would rather be constant as set by the operator. END — Section 4.1 — The initial LSP bandwidth can be set to an arbitrary value (including zero), in practice, it can be operator expected value based on design and planning. NEW The initial LSP bandwidth can be set to an arbitrary value (including zero). In practice, it can be set to an expected value based on design and planning. END — Section 4.2 — When the Auto-Bandwidth feature is enabled, the measured traffic rate is periodically sampled at each Sample-Interval (which can be configured by an operator and the default value as 5 minutes) by the PCC, when the PCC is the head-end node of the LSP. The traffic rate samples are accumulated over the Adjustment-Interval period (in the Up or Down direction) (which can be configured by an operator and the default value as 24 hours). NEW When the Auto-Bandwidth feature is enabled, the measured traffic rate is periodically sampled at each Sample-Interval by the PCC, when the PCC is the head-end node of the LSP. The sample interval can be configured by an operator, with a default value of 5 minutes. The traffic rate samples are accumulated over the Adjustment-Interval period (in the Up or Down direction). The period can be configured by an operator, with a default value of 24 hours. END The PCC, in-charge of calculating the bandwidth to be adjusted, can decide to adjust the bandwidth Remove both commas. Only if the difference between the current bandwidth demand (MaxAvgBw) and the current bandwidth reservation is greater than or equal to the Adjustment-Threshold (percentage or absolute value) (which can be configured by an operator and the default as 5 percentage), the LSP bandwidth is adjusted (upsized) to the current bandwidth demand (MaxAvgBw). I’m sorry: I can’t made any sense out of this text and, thus, can’t suggest a fix. Please try rephrasing this. When you do, please make it more than one sentence, and please avoid consecutive parenthesized phrases, which are awkward. However, longer adjustment-interval can result in an undesirable effect “a longer” To avoid this, the Auto-Bandwidth feature may pre-maturely expire the adjustment- interval and adjust the LSP bandwidth “prematurely”, with no hyphen. “adjustment interval”, with no hyphen. — Section 5.1 — o The PCEP speaker that does not recognize the extensions defined in “A PCEP speaker” o If the PCEP speaker that supports the extensions defined in this “If a PCEP speaker supports” — Section 5.2 — Future specification can define additional sub-TLVs. “specifications” If sub-TLVs are not present, the default values as specified in this document are used or otherwise based on the local policy are assumed. I can’t make sense of that sentence; please re-phrase it. — Section 220.127.116.11 — o Reserved: SHOULD be set to zero on transmission and MUST be ignored on receipt. Why is this “SHOULD”, when other reserved values have been “MUST”? (Same comment in 18.104.22.168, 22.214.171.124, 126.96.36.199, 188.8.131.52, and 184.108.40.206.)