多项选择题 You are about to configure PPP n the interface of a Cisco router. Which authentication methods could you use?（）

单项选择题 Which of the following Frame-Relay encapsulation commands would you use, if you had to connect your Cisco router to a non-Cisco router?（）

单项选择题 A new frame-relay network is being implemented and inverse ARP does not appear to be operating correctly. Which alternative command can be used to provide connectivity?（）