多项选择题
A. TCP-based hello packets
B. the impact of flapping links if timers are too low
C. a shared single interface
D. the ability to track serial interfaces
E. UDP-based hello packets
多项选择题 What are two characteristics of the relationship between the Cisco PIN architecture and CiscoValidated Designs? （）(Choose two.)
多项选择题 Which three of the following steps are mandatory when configuring MPLS on Cisco IOS?（）(Choose three.)
单项选择题 Which command retrieves and displays information about each Cisco product in the form of aUDI?（）