单项选择题
A. performing inter - VLAN routing
B. performing 802.1Q trunking
C. performi ng ISL trunking
D. Ethernet Switch Module installed
E. ADSL WIC installed
F. running Call Manager Express
单项选择题 What is the international standard for transmitting data over a cable sys tem?（）
单项选择题 What is the purpose of configuring the router as a PPPoE client?（）
单项选择题 Which DSL encapsulation method requires client software running on the end - user PC that is directly connected to a DSL modem?（）