Outbound Connections

Connection Type	Direction	Description
upstreamHubs	Bidirectional	Used for non-core servers for connection to a higher tier server. Only one upstreamHubs connection is active at a time. Only packets received from inbound ports are sent to the upstream server. upstreamHubs is mutually exclusive with upstreamHubsRO and hubs.
upstreamHubsRO	Receive Only	Used for non-core servers for connection to a higher tier server. Only one upstreamHubsRO connection is active at a time.
hubs	Receive Only	Used for non-core servers for connection to a higher tier servers.
srvrToSrvrPorts	UDP Only	Used by core servers to exchange packets.