A Cisco Aironet Wireless LAN Adapter CB21AG is inserted into a user’s PC cardbus slot. Both the green status LED and the amber activity LED are blinking slowly. 
What is the condition of the adapter？ （）

单项选择题You suspect that a hacker may be performing a MAC address flooding attack somewhere within the    network.  Which description correctly describes a MAC address flooding attack？（）

A.The attacking device spoofs a source MAC address of a valid host currently in the CAM table. The switch then forwards frames destined for the valid host to the attacking device.
B.Frames with unique， invalid destination MAC addresses flood the switch and exhaust CAM table space. The result is that new entries cannot be inserted because of the exhausted CAM table space， and traffic is subsequently flooded out all ports.
C.The attacking device crafts ARP replies intended for valid hosts. The MAC address of the attacking device then becomes the destination address found in the Layer 2 frames sent by the valid network device.
D.The attacking device crafts ARP replies intended for valid hosts. The MAC address of the attacking device then becomes the source address found in the Layer 2 frames sent by the valid network device.
E.The attacking device spoofs a destination MAC address of a valid host currently in the CAM table. The switch then forwards frames destined for the valid host to the attacking device.
F.Frames with unique， invalid source MAC addresses flood the switch and exhaust CAM table space. The result is that new entries cannot be inserted because of the exhausted CAM table space， and traffic is subsequently flooded out all ports.
G.None of the other alternatives apply

单项选择题Study the exhibit shown below carefully. In this scenario the service provider wants to ensure that switch S1 is the root switch for its own network and the network of .  On which interfaces should root guard be configured to ensure that this happens？（）

A.Interfaces 11 and 12
B.Interfaces 1， 2， 3， and 4
C.Interfaces 5 and 6
D.Interfaces 5， 6， 7， and 8
E.Interfaces 1 and 2
F.Interfaces 1， 3， 5， and 6

多项选择题In order to enhance worker productivity， a Cisco wireless network has been implemented at all    locations.  Which three statements regarding WLAN are true？（）

A.A WLAN client will operate in half-duplex mode.
B.The Aironet 1230 access point is an example of an access point that operates solely as a lightweight access point.
C.Ad hoc mode allows mobile clients to connect directly without an intermediate AP.
D.WLANs are designed to share the medium and can easily handle an increased demand of channel contention.
E.A lightweight AP receives control and configuration from a WLAN controller to which it is associated.
F.Another term for infrastructure mode is independent service set （IBSS）.

单项选择题Switch 1 was configured as shown below： Based on the output shown above，  which statement is true？ （）

A.IP traffic matching access list    is forwarded through VLANs 5-10.
B.All VLAN traffic in VLANs 5-10 that match access list    will be forwarded， and all else will be dropped.
C.IP traffic matching VLAN list 5-10 will be forwarded， and all other traffic will be dropped.
D.All VLAN traffic matching VLAN list 5-10 will be forwarded， and all traffic matching access list    is dropped.
E.None of the other alternatives apply

多项选择题WhichofthefollowingarefunctionsthatareoftenprovidedbyanITSPbutarenottypicallyprovidedbythePSTN？（）

A. QoS
B. call setup and teardown
C. call routing
D. call supervision
E. audio signal compression