Originating peer identifier. Combined with id to form the compound key
the reconciler uses to locate prior entries on transient/cancel/commit.
Two peers can each maintain their own per-session id counter without
collision provided each peer's userId is unique.
Originating peer identifier. Combined with
idto form the compound key the reconciler uses to locate prior entries on transient/cancel/commit. Two peers can each maintain their own per-session id counter without collision provided each peer'suserIdis unique.