Although many approaches to dynamic reconfiguration have been proposed, how the impact of reconfiguration on system QoS can be controlled has not been addressed adequately so far. In this paper, we propose an approach to dynamic reconfiguration of distributed data flow systems. It is an improvement of our previous work for dynamic reconfiguration with QoS management into distributed environment. Our approach has three features. First, it uses version control, flow trace, and reconfiguration scheduling to avoid logical and physical impact on system QoS. Second, it plans a reconfiguration in a totally automatic way. Third, it executes a reconfiguration by a decentralized protocol to reduce reconfiguration time in distributed environment. We adopt our approach to the reconfiguration of a real world application, the Data Encryption and Digital Signature System. Experimental results show that our approach has significant advantages in impact control comparing with other existing approaches.