交换虚拟电路 meaning in Chinese

svc
switched virtual circuit

Svc switched virtual circuit
交换虚拟电路
However , the concern is that voice traffic in frame environments built with permanent virtual circuits ( pvc ) will not be as cost - effective as frame nets built with switched virtual circuits ( svc )
但问题是，用永久虚拟电路（ pvc ）建立起来的帧环境中的话音通信的性能价格比不如用交换虚拟电路（ svc ）建立起来的帧网络。