In the following essay,each blank has four choices.Choose
the most suitable onefrom the follow choices and write down in the answer
sheet. Open Shorest Path First(OSPF)is a
25 routing algorithm that 26
work doneon the OSI IS.IS intradomain routing protocol.This
routing, as compared to distance-vectorrouting,requires
27 processing power.The 28
algorithm is used to calculate routes.OSPF routing table updates
only take place when necessary, 29 at
regular intervals. 供选择的答案网络中某用户只能接收但不能发送Email,此时管理员应检查。