A. 分组交换数据网X.25
B. DDN数字数据网(Digital Data Network)
C. 祯中继网(Frame Relay)
D. ISDN(Integrated Service Digital Network)
(责任编辑:admin) |
A. 分组交换数据网X.25
B. DDN数字数据网(Digital Data Network)
C. 祯中继网(Frame Relay)
D. ISDN(Integrated Service Digital Network)
(责任编辑:admin) |