OSPF notes [multiple access, two multicast addresses with OSPF]

MA The Internet ： Also called multi access network , The so-called multi access network means that a piece of physical information can be sent to other routers on the same network . A typical example is ： A layer-2 switch is connected to multiple routers , At this time, every two routers can communicate with each other . We do this MA【 Multiple access to the network 】

MA There are two types of networks ： One is BMA Broadcast multiple access network [ for example ： The layer-2 switch mentioned above is connected to the router ], The other is NBMA Non broadcast multiple access network [ for example ： Frame relay ].

OSPF The multicast address of :OSPF There are two multicast addresses. One is 224.0.0.5[ Occurs to be-all OSPF Router ];224.0.0.6[ Occurs to be-all OSPF DR Router { About DR, link ：DR And BDR}]