多项选择题
A. supports multiple protocols
B. works only in a shared or loop environment
C. allows addressing for up to 4 million nodes
D. provides a high speed transport for SCSI payloads
单项选择题 What is one of the reasons that custom QoS ACLs are recommended over automatic QoS when configuring ports on a Catalyst 6500 for use with IP phones?（）
单项选择题 VLAN Tagging, also known as Frame Tagging, is a method developed by Cisco to help identify packets travelling through trunk links. When an Ethernet frame traverses a trunk link, a special VLAN tag is added to the frame and sent across the trunk link .How does ERS use the VLAN tag?（）
单项选择题 When is the site-to-site remote access model appropriate? （）