Which two of these are recommended practices with trunks？（）

多项选择题Whichtwodesignconcernsmustbeaddressedwhendesigningamulticastimplementation？（）

A.only the low-order 23 bits of the MAC address are used to map IP addresses
B.only the low-order 24 bits of the MAC address are used to map IP addresses
C.only the high-order 23 bits of the MAC address are used to map IP addresses
D.only the low-order 23 bits of the IP address are used to map MAC addresses
E.the 0x01004f MAC address prefix is used for mapping IP addresses to MAC addresses
F.the 0x01005e MAC address prefix is used for mapping IP addresses to MAC addresses

单项选择题Lafeyette Productions is looking for a new ISP that has improved availability, load balancing, and catastrophe protection. Which type of ISP connectivity solution would be best?（）

A. single run
B. multi-homed
C. stub domain EBGP
D. direct BGP peering

单项选择题You are the Cisco Network Designer in Cisco.com. Which statement is correct regarding NBAR and NetFlow?（）

A. NBAR examines data in Layers 1 and 4.
B. NBAR examines data in Layers 3 and 4.
C. NetFlow examines data in Layers 3 and 4.
D. NBAR examines data in Layers 2 through 4.

单项选择题Whichsite-to-siteVPNsolutionallowsCiscorouters，PIXFirewalls，andCiscohardwareclientstoactasremoteVPNclientsinordertoreceivepredefinedsecuritypoliciesandconfigurationparametersfromtheVPNheadendatthecentralsite？（）

A.Easy VPN
B.GRE tunneling
C.Virtual Tunnel Interfaces
D.Dynamic Multipoint VPN
E.Group Encrypted Transport VPN

单项选择题WhyisSTPrequiredwhenVLANsspanaccesslayerswitches？（）

A.to ensure a loop-free topology
B.to protect against user-side loops
C.in order to support business applications
D.because of the risk of lost connectivity without STP
E.for the most deterministic and highly available network topology