单项选择题 In comparison with traditional Layer 2 and Layer 3 system, Cisco Catalyst 6500 Virtual Switching System (VSS) 1440 simplifies a network by the means of:（）

单项选择题 You are working with a client to deploy QoS on their Frame Relay WAN. They would like to be able to allow packets to cross the Frame Relay WAN but have them marked as discard eligible if they exceed the QoS policy. How would you accomplish this task?（）

单项选择题 What is a new feature of the Cisco ISR router? （）