1. [单选题]On a half-duplex Ethernet LAN, two hosts attempt to send data simultaneously, resulting in a collision. Following this collision, what will the hosts do? (Select all valid answers)
A. The destination host sends a request to the source for retransmission.
B. The jam signal indicates that the collision has been cleared.
C. The hosts will attempt to resume transmission after a time delay has expired.
D. An electrical pulse indicates that the collision has cleared.
E. The router on the segment will signal that the collision has cleared.
F. F. The hosts will do nothing, as the higher layers are responsible for data error correction and re-transmission.
2. [单选题]RIP路由协议认为“网络不可到达”的跳数是：()
A. 8
B. 16
C. 24
D. 100
3. [单选题]交换机转发数据到目的地依靠()
A. 路由表
B. MAC地址表
C. 访问权限表
D. 静态列表
4. [单选题]能够分配给设备的IP，应该是（）
A. 网络有效IP
B. 网络号
C. 网络广播地址
D. 任意IP
5. [单选题]帧中继(frame relay)环境中，在物理端口上，建立子接口的命令是（）
A. create
B. interface
C. encapsulation
D. ip address
