In large service provider and Enterprise networks, some distribution-layer routers often have a large number of interfaces, for example, at the WAN edge. A common practice to facilitate the configuration of a routing protocol on such routers is to en...
http://www.ebrahma.com/2013/10/how-to-configure-ospf-passive-interface/Labels: confiure-passive-interace, neighbor-relationships, OSPF-Passive-Interface, OSPF-routin, OSPF-updates, passive