A lot of work has been done in developing energy efficient network and user devices to reduce the power consumption of nodes and devices in networks. This thesis proposes an innovative approach using fuzzy logic for power saving and extending the life time of network nodes and user devices. Using the concept of silent networking we will define an actionable silent period-this is the period during which the network node or the user device does not expect to originate, receive or relay any traffic. The decision of switching the network interface or user device in the silent mode depends on the history of the network activity. Secondly, if the actionable silent period is high enough, then we can switch the entire interface in power down mode leaving just the timer ON to wake up the interface at the end of silent period. Fuzzy logic is used in mapping the history of the network interface and based on the fuzzy rules that we define, the actionable silent period for interfaces is formulated. Experimental analysis using simulations has been done to view the power saving that can be achieved using this method. Furthermore, a methodology for extending the lifetime of the networked devices is formulated. Using this innovative approach we can save a considerable amount of energy and proportionally increase the lifetime of the networked devices.