Most routing protocols have metric structures and algorithms that are not compatible with other protocols. In a network with multiple routing protocols, the exchange of route information and the capability to select the best path across the multiple protocols are critical.elect the Best Path. Administrative distance is the first criterion that a router uses to determine which routing protocol to use if two protocols provide route information for the same destination. Administrative distance is a measure of the trustworthiness of the source of the routing information.
In July 2013, China heralded the opening of the New Century Global Center, an immense 18.9-million-square-foot (1.75 million square meters) structure that many are calling the largest building in the world.
1. Ping An Finance Center, China, by Kohn Pedersen Fox. The tallest building completing in 2016 is a 599-metre tower in Shenzhen by US firm Kohn Pedersen Fox (KPF). Once complete, it will steal the title of world's tallest office building from One World Trade Center in New York. It will also be the fourth tallest building on earth.