If nullptr, the node creates its own communicator.
Remarks
A DataStorm node requires the requests it receives on a connection to be dispatched in the order they were sent; a partial update is applied to the value left by the preceding sample. A node configures the communicators it creates accordingly, but it does not change the configuration of a communicator supplied here. Such a communicator must set Ice.ThreadPool.Client.Serialize to 1 before it is created. An executor set through Ice::InitializationData must likewise preserve the dispatch order.
1.17.0 