单项选择题
A. show users
B. show connected
C. show subscribers
D. show ip subscribers
单项选择题 Which configuration command limits the number of connections supported on a single PPPoE major interface?（）
单项选择题 Which configuration command prevents a client from establishing multiple PPPoE connections from a single workstation?（）
单项选择题 A metro Ethernet user is connected using a PPP over Ethernet service.How many Layer 2 headers are attached to each IP datagram?（）