A conflict resolution technique provides consistency such that all
conflicts can be detected by at least one of the conflicting requestors
if each node monitors all requests after that node has made its own
request. If a line is in the Exclusive, Modified or Forward state,
conflicts are resolved at the node holding the unique copy. The winner of
the conflict resolution, and possibly the losers, report the conflict to
the home node, which pairs conflict reports and issues forwarding
instructions to assure that all requesting nodes eventually receive the
requested data. If a requested cache line is either uncached or present
only in the Shared state, the home node provides a copy of the cache node
and resolves conflicts. In one embodiment, a blackout period after all
responses until an acknowledgement message has been received allows all
conflicting nodes to be aware of conflicts in which they are involved.