Does the propagation implementation support sharing client and server span IDs. For example,
should an RPC server span share the same identifiers extracted from an incoming request?
In usual
B3 Propagation, the
parent span ID is sent across the wire so that the client and server can share the same
identifiers. Other propagation formats, like
trace-context
only propagate the calling trace and span ID, with an assumption that the receiver always
starts a new child span. When join is supported, you can assume that when
TraceContext#parentId() is null, you've been propagated a root span. When
join is not supported, you must always fork a new child.