1. [单选题]TELNET工作在OSI哪一层（）
A. 会话层(session layer)
B. 表示层
C. 传输层
D. 应用层
2. [单选题]对于路由表，下列说法中正确的是：（）
A. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示RIP发现的路由，因为RIP协议的优先级更高
B. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示OSPF发现的路由，因为OSPF协议的优先级更高
C. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示RIP发现的路由，因为RIP协议的花费值（metric）更小
D. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示OSPF发现的路由，因为OSPF协议的花费值（metric）更小
3. [单选题]为了连接“帧中继(frame relay)”线路，网络中的路由器需要提供的端口类型为（）
A. FastEthernet
B. Serial
C. BRI
D. Ethernet
4. [多选题]Which of the following statements correctly describe the differences between half-duplex and full-duplex Ethernet? (Select two answer choices.)
A. Full-duplex Ethernet uses CSMA/CD to prevent collisions.
B. Half-duplex Ethernet uses a loopback circuit to detect collisions.
C. A full-duplex Ethernet card allows 20Mbps for data transmission.
D. Full-duplex Ethernet makes use of two pairs of wires for data.
E. An Ethernet hub can operate both half and full duplex simultaneously.
5. [单选题]You need to decide on which trunking method to implement in the Ezonexam network. What is a characteristic of ISL and 802.1q frame. tagging in a switched LAN environment?
A. They are used to find the best path through a network.
B. They allow the exchange of filtering tables.
C. They specify different implementations of the Spanning-Tree Protocol.
D. They allow the exchange of routing tables
E. They provide inter-switch VLAN communication.
