[RPRWG] Unclear from D2.0 what Protection messages are transmitted on each ringlet.

["Michael Allen" <michael_allen@xxxxxxxxxxxxxxx>]

I am currently trying to implement the Protection algorithms from D2.0 and
am finding some ambiguities/missing detail.

The spec discusses a "Long" and "Short" protection message and describes
what each message indicates. What the spec does not indicate is what
messages are actually transmitted in IDLE/WRAPPED/PROTECTION conditions.

I.e. Is a short AND long message sent on each ringlet in each periodic
interval? This way both interfaces are described in both directions on the
ring. This would mean each station originates 4 messages per interval.

If only a single message is sent on each ringlet, which interface is the
fail_status reporting and is it different for IDLE/WRAPPED/PROTECTION
states?

In 11.8.3 c), allowNonCoexistingProtection...
I find the statement "all link availability values in topology database not
corresponding to sideProtectionState and neighborProtectionState" quite
ambiguous.

1) For the comparison, is this all fail_status values on both ringlets
(except those noted)?
2) Is neighborProtectionState to exclude the one for the neighbor state
received on the ringlet being processed, or for both the ringlet
neighborProtectionStates on neighbor?
3) Is sideProtectionState to excluded just that for the ringlet being
processed.

Hope these questions are clear,

Regards,

Michael Allen
Chip Engines, Inc.