Which of these is a Layer 2 transport architecture that provides packet-based transmission optimized for data based on a dual （counter-rotating） ring topology？（）

单项选择题OneofyourcustomerswishestousetheNAStoperformDHCPfunctionsanddoesnotcurrently haveaLayer3gatewayinitsproductionnetwork.Whichgatewaymodeisappropriateforthis customer？（）

A. Virtual Gateway
B. Real-IP Gateway
C. NAT Gateway
D. IP-IP Gateway

单项选择题YourMPLSimplementationiscurrentlyusinginternalbackdoorlinks.Whatcanyoudotominimize theimpactofhavingtheselinks？（）

A. use BGP as the CE-PE routing protocol
B. use OSPF as the CE-PE routing protocol
C. use EIGRP as the CE-PE routing protocol
D. use the SP to redistribute routes as external routes for OSPF and EIGRP
E. use route redistribution at each location to ensure external routes are imported into the IGP

单项选择题WhichoftheseistrueofaLayer3out-of-bandNASdeployment？（）

A. The NAS acts as a gateway for all Layer 3 traffic.
B. Only the MAC address is used to identify the client device.
C. User traffic remains on the same VLAN for the duration of the connection.
D. After authentication and posture assessment， client traffic no longer passes through the NAS.

多项选择题WhichthreeoftheseareimportantwhendeterminingNASServerscaling？（）

A. interface bandwidth
B. rescan timer interval
C. total number of network devices
D. number of new user authentications per second
E. which operating system is loaded on the client
F. number of checks performed in a posture assessment

多项选择题WhichtwoofthesearecharacteristicsofMetroEthernet？（）

A. class of service
B. bandwidth profiles
C. user-network interface
D. Ethernet LAN circuit attributes
E. Ethernet virtual circuit attributes