Subject: [CCAMP] Addressed comments on draft-takacs-ccamp-revertive-ps-07 from last IETF

From: "Zafar Ali (zali)" <[email-masked]>
Date: Tue, 26 Feb 2013 07:07:28 +0000

Hi Lou and all:

Lou, et al made a comment that it has been quite a few IETF-s since the draft was presented and may be there are some other mechanisms deviced by now (e.g., via OAM work).

Authors of draft-takacs-ccamp-revertive-ps-07 followed up on this Action Item but did not find much that exists or is applicable to the requirement addressed by draft-takacs-ccamp-revertive-ps-07. Details are in the following.

In the light of this we believe draft-takacs-ccamp-revertive-ps-07 solves a real problem of signaling protection switching characteristics (hold-off, wtr, snc-mode). We will be happy to address any comments from the WG but believe that this draft should be adapted by the WG.

Thanks

Regards … Zafar (on behalf of my co-authors).

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Details
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This is based on an email thread among co-authors. Much of the following is quoting Francesco Fondelli' response.

The only thing we found was the Revert field in https://tools.ietf.org/html/rfc6378#page-18. But Protection State Coordination Protocol (PSC) is orthogonal to takacs-ccamp-revertive-ps.

In SDH or OTN or any other GMPLS-controlled technology that support proper protection switching we have an indication in the "horizontal OAM protocols" about revertive/no-revertive nature of the protection switching in use.

These "horizontal OAM protocols" (i.e. PSC for MPLS-TP, APS for SDH, another-form-of-APS for OTN, proprietary-APS for WDM) are used to coordinate between both ends of the protection domain in order to select the proper traffic flow (i.e. the providing service path).

takacs-ccamp-revertive-ps is not about that, is about *signaling and appropriately establish* these flows (LSPs).  Both mechanisms might live together.