NetData is a String property that represents the storage used for data passed between the local client Connection and the OutboundClient connection for the proxied client session. 

NetData is updated and used during execution of the task when TIdMappedPortTCP triggers execution of the client context. Socket handles in DataAvailList are used to determine when values are available from the local client Connection or the OutboundClient connection for the proxied session. 

During execution, values available from the local client Connection is read and stored in NetData for subsequent use in the OnExecute event handler for the server. Non-blank values in NetData are written to the OutboundClient connection following execution of the event handler. 

Values available from the OutboundClient connection is also read and stored in NetData for subsequent use in the OnOutboundClientData event handler for the server. Non-blank values in NetData are written to the local client connection following execution of the event handler. 

Values in NetData can be modified or removed in either event handler prior to transmission to its ultimate destination.

DataAvailList Connection OutboundClient TIdMappedPortTCP.OnExecute TIdMappedPortTCP.OnOnOutboundClientData