1. [多选题]What are two characteristics of "store and forward" switching? (Select two answer choices)
A. Latency fluctuates regardless of frame. size.
B. The switch receives the complete frame. before beginning to forward it.
C. Latency through the switch varies with frame. length.
D. The switch checks the destination address upon receipt of headers.
2. [单选题]介质工作在OSI的哪一层（）
A. 物理层
B. 数据链路层(data link layer)
C. 网络层
D. 传输层
3. [单选题]把访问权限表应用到路由器端口的命令是：()
A. permit access-list 101 out
B. ip access-group 101 out
C. apply access-list 101 out
D. access-class 101 out
4. [单选题]在OSPF的完全存根区域中，使用以下哪种LSAType报文或其它方式与区域间通信：（）
A. LSAType1.2
B. LSAType3
C. LSAType4
D. 默认路由：0.0.0.0
5. [单选题]在OSI七层模型中，介质工作在哪一层()
A. 传输层
B. 会话层(session layer)
C. 物理层
D. 应用层
