In my previous mails, I used the term "persistent state desynchronisation".
Since this apparently worried some people, so I guess I'll explain.

DNCP uses dynamic timers (Trickle) to flood a hash of the global state and
separate unicast request/response pairs to propagate actual data.  Bad
things will happen if the hash is successfully flooded but the data cannot
be propagated, for example because it doesn't fit in the maximum packet
size, because a node is not publishing enough NEIGHBOR TLVs, or because of
implementation bugs.

More precisely, under such circumstances each attempt to flood the
inconsistent network hash is followed with a flurry of request/response
pairs and a reset of the Trickle timers to their minimal value (200ms).
The result is persistent spam.

Therefore, (1) we must make sure that a compliant implementation does not
cause state to become persistently inconsistent, and (2) we should develop
some mechanism that detects persistently desynchronised neighbours and
rate-limits them.  (1) needs to go in the spec, while (2) is a "mere"
implementation detail.

-- Juilusz

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