Methods and systems are described for disabling an operative coupling to a network. In an aspect, first data received for forwarding is forwarded between a first node in a first network and a second node in a second network by a network relay via a first operative coupling to the first network of a first network interface hardware component in the network relay and via a second operative coupling to the second network of a second network interface hardware component in the network relay. A determination is made that a specified decoupling condition is met. The second operative coupling is disabled subsequent to the forwarding and in response to the determination while the first operative coupling remains enabled for receiving second data for forwarding.