【名词&注释】
校验位(parity bit)、防火墙、数据通信(data communication)、主存储器(main memory)、无线电通信(radio communication)、绝对值(absolute value)、错误码、奇偶校验(parity check)、低分辨率(low resolution)、发生变化
[单选题]A ______ system placed between the company network and the outside world may limit outside access to the internal network.
A. firewall
B. modem
C. gateway
D. key
B. ping-s 202.38.75.14 C. ping boozhang@sdb.ac.cm D. ping http://www.zsu.edu.cn
B. 场 C. 矢量 D. 低分辨率(low resolution)