预约成功后，不错过重要时期

2018上半年网络工程师英语真题

责编：胡媛 2018-09-01

With circuit switching a __(1)__path is established between two stations for communication . Switching and transmission resources within the network are __(2)__for the exclusive use of the circuit for the duration of the connection . The connection is__(3)__：Once it is established ，It appears to attached devises as if there were a direct connection. Packet switching was designed to provide a more efficient faciltiy than circult switching for ( ) data tratffic. Each packet contains some portion of the user data plus control information needed for proper functioning of the network. A key distinguishing element of packet_switching networks is whether the internal operation is datagram or virtual circuit . With internal virtual circuits,a route is defined between two endpoints and all packets for that virtual circuit follow the__(4)__ route, With internal datagrams,each packet is treated independently,and packets intended for the same destination may follow different routes.

（1）A．unique

B. dedicated

C. nondedicated

D.independent

（2）A．discarded

B. abandoned

C. reserved

D. broken

（3）A． indistinct

B.direct

C.indirect

D. transparent