“我是天空里的一片云,偶尔投影在你的波心”出自于哪位诗人之手?()
A、戴望舒
B、闻一多
C、李金发
D、徐志摩
参考答案:D
Networks can be interconnected by different devices. In the physical layer, networks can be connected by (11) or hubs, which just move the bits from one network to an identical network. One layer up we find bridges and switches, which operate at data link layer. They can accept (12) ,examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two networks. If two networks have (13) network layer, the router may be able to translate between the packer formats. In the transport layer we find transport gateway, which can interface between two transport connections. Finally, in the application layer, application gateways translate message (14) . As an example, gateways between Internet e-mail and X.400 e-mail must (15) the e-mail message and change various header fields.
A. repeaters B. relays C. packages D. modems
汽包壁温的测点是如何分布的?