OSPF is a link-state routing protocol。It is designed to be run internal to a single __（71__system。Each OSPF router maintains an identical __（72）__ describing the autonomous system’s topology。From this database，a routing table is calculated by constructing a shortest-path __（73）__。OSPF recalculates routes quickly in the face of topological changes，utilizing a minimum of routing __（74）__ traffic。OSPF provides support for equal-cost multipath。An area routing capability is provided，enabling an additional level of routing protection and a reduction in routing protocol __（75）__。

（73）

（74）

（75）

OSPF is a link-state routing protocol。It is designed to be run internal to a single __（71__system。Each OSPF router maintains an identical __（72）__ describing the autonomous system’s topology。From this database，a routing table is calculated by constructing a shortest-path __（73）__。OSPF recalculates routes quickly in the face of topological changes，utilizing a minimum of routing __（74）__ traffic。OSPF provides support for equal-cost multipath。An area routing capability is provided，enabling an additional level of routing protection and a reduction in routing protocol __（75）__。

（72）

SNMP协议使用的协议和默认端口为__（68）__。

在Windows操作系统中，某主机运行rout print命令后路由记录如下图所示，则主 机的默认网关为__（69）__；与rout print具有同等功能的命令是__（70）__。

（70）

以下关于DHCP协议的描述中，错误的是__（66）__。

某主机要访问www.bbb.com，主域名服务器为202.117.112.5，辅助域名服务器为 202.117.112.6，域名www.bbb.com的授权域名服务器为102.117.112.3，则这台主机进行该域名解析时最先查询的是__（67）__。