A major concern in modern explosive development of information and communication technology, especially in wired networking is to reduce of unnecessary energy consumption. It is needed because of expected environmental impact and potential economic benefits. These issues are usually referred as “Green networking”. It is related to increase the awareness of energy consuming in routing protocols, in the devices, including the structure of the whole networking system. Here different issues will be described which is topically related and the possible impact in green networking field. Also, special attention will be monitored in the routing protocol and algorithm especially link state routing protocol which is generally used for calculating the shortest path. This research paper tries to find out a new technique or modified routing technique that will be more effective for every router in terms of energy efficiency.

Data transmission is one of the most important term used in our day to day activities in the fast-growing world. Li-Fi opens a new era to that. Li-Fi is known as Light Fidelity. Simply it transmits data by visible light. According to recent research Li-Fi has a range of approximately 10 meters. Also, it cannot pass through wall or any solid object. So, this research focuses mainly to increase the 10-meter range. For a regular sized room this range is enough. But if anyone wants to provide data inside a big hall or in any large room, it is not possible by only this range. He must provide more LED that is connected to the Li-Fi router. This research focuses to optimize the number of LED and to minimize the cost. To increase the range of LED two methods are proposed here. One of the method deals with the positioning of the LEDs and another method is to use concave mirror. Smarter way of positioning of light gives better coverage of light that increases the range of LED. As concave mirror gives real and increased mirror for a particular positioning of an object, which is proved both theoretically and mathematically.