public PduHandle sendPdu(
     Address transportAddress,
     int messageProcessingModel,
     int securityModel,
     byte[] securityName,
     int securityLevel,
     PDU pdu,
     boolean expectResponse)
     throws MessageException {
   return dispatcher.sendPdu(
       transportAddress,
       messageProcessingModel,
       securityModel,
       securityName,
       securityLevel,
       pdu,
       expectResponse);
 }
 @Override
 public PduHandle sendPdu(
     TransportMapping transportMapping,
     Address transportAddress,
     int messageProcessingModel,
     int securityModel,
     byte[] securityName,
     int securityLevel,
     PDU pdu,
     boolean expectResponse,
     PduHandleCallback callback)
     throws MessageException {
   return dispatcher.sendPdu(
       transportMapping,
       transportAddress,
       messageProcessingModel,
       securityModel,
       securityName,
       securityLevel,
       pdu,
       expectResponse,
       callback);
 }