Hi Julien You are right, but it is *really easy* for the reader to confuse "stateful capability" with "update capability" and "active stateful capability". Case in point: I just confused them in my reply to Lionel.
We should fix each of the three points below to make this clearer. Cheers Jon -----Original Message----- From: Julien Meuric [mailto:julien.meu...@orange.com] Sent: 11 April 2017 16:00 To: Jonathan Hardwick <jonathan.hardw...@metaswitch.com>; Lionel Morand <lionel.mor...@orange.com>; ops-...@ietf.org Cc: draft-ietf-pce-stateful-pce....@ietf.org; pce@ietf.org; i...@ietf.org Subject: Re: [Pce] Review of draft-ietf-pce-stateful-pce-18 Jon, Lionel, I believe Lionel got confused by the wording introduced in RFC 8051: - no report, no update means stateless PCE; - report, no update means passive stateful PCE; - report and update means active (stateful) PCE. More details below, [JM]. Thanks for the work, Julien Apr. 11, 2017 - jonathan.hardw...@metaswitch.com: > ===== > > [LM] active/passive mode are not advertized in PCEP. s/if active > stateful PCE capability was not advertised/if stateful PCE capability > was not advertised > > Jon> ACK > > ===== [JM] NACK! ;-) Actually, the passive mode is advertised using the Stateful-capability-object TLV with the U bit unset, the active mode by setting the U bit. > ===== > > Note that even if the update capability has not been advertised, a PCE > can still accept LSP Status Reports from a PCC and build and maintain > an up to date view of the state of the PCC's LSPs. > > [LM] I don't undersand. Is it not in contradiction with > > "If the PCEP Speaker on the PCE supports the extensions of this draft > but did not advertise this capability, then upon receipt of a PCRpt > message from the PCC, it MUST generate a PCErr with error- type > 19 (Invalid Operation), error-value 5 (Attempted LSP State Report if > active stateful PCE capability was not advertised) (see Section > 8.5) and it SHOULD terminate the PCEP session." > > Or does it mean that there is another way than PCRpt message for the > PCC to send LSP status reports to the PCE? > > Jon> ACK. I think that the statement in the draft is bogus and I > propose to delete this sentence from it. > > ===== [JM] I do not think that the text is bogus: - case 1: no advertised capability on update but advertised on report (i.e. passive stateful) => no error message; - case 2: no advertised capability on update nor report (i.e. stateless) => error. > ===== > > [LM] Would it be useful to discover (using another TLV) whether the > PCE is an active/passive stateful PCE, as in IGP-based capabilities > discovery mechanism? > > Jon> This can be inferred immediately from the U flag in the > STATEFUL-PCE-CAPABILITY TLV. Passive mode is synonymous with not > sending / handling PCUpd messages. > > ===== [JM] The mechanism is there, but section 7.1.1 may deserve an explicit use of the "passive/active" terms, to make sure the capability terminology is aligned with the vocabulary in the IGP section. _______________________________________________ Pce mailing list Pce@ietf.org https://www.ietf.org/mailman/listinfo/pce
