System.Web.UI.WebControls.WebParts.ProviderConnectionPoint objects have their ConnectionPoint.AllowsMultipleConnections property value set to true (by the System.Web.UI.WebControls.WebParts.ConnectionProviderAttribute class), because the Web Parts control set by default enables provider connection points to form connections to multiple consumers.

In contrast, System.Web.UI.WebControls.WebParts.ConsumerConnectionPoint objects have their ConnectionPoint.AllowsMultipleConnections property value set to false (by the System.Web.UI.WebControls.WebParts.ConnectionConsumerAttribute class) because the Web Parts control set by default allows consumer connection points to establish a connection to only one provider at a time.

You can change the default behavior concerning multiple connections by assigning different values to the ConnectionProviderAttribute.AllowsMultipleConnections property (for providers) or the ConnectionConsumerAttribute.AllowsMultipleConnections property (for consumers) on the two Attribute classes used for connection attributes. If you enable consumer connection points to connect to multiple providers at the same time, your code must deal with any resulting synchronization issues.