  Dynamic network reconfiguration is described as the process of replacing one
routing function with another while the network keeps running. The main
challenge is avoiding deadlock anomalies while keeping limitations on message
injection and forwarding minimal. Current approaches, whose complexity is so
high that their practical applicability is limited, either require the
existence of extra network resources like virtual channels, or they affect the
performance of the network during the reconfiguration process. In this paper we
present a simple, fast and efficient mechanism for dynamic network
reconfiguration which is based on regressive deadlock recoveries instead of
avoiding deadlocks. The mechanism which is referred to as DBR guarantees a
deadlock-free reconfiguration based on wormhole switching (WS) and it does not
require additional resources. In this approach, the need for a reliable message
transmission has led to a modified WS mechanism which includes additional flits
or control signals. DBR allows cycles to be formed and in such conditions when
a deadlock occurs, the messages suffer from time-out. Then, this method
releases the buffers and channels from the current node and thus the source
retransmits the message after a random time gap. Evaluating results reveal that
the mechanism shows substantial performance improvements over the other methods
and it works efficiently in different topologies with various routing
algorithms.
