Ccna certification Practice Tests

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 167.  B.  The 2.4 GHz frequency spectrum is where Bluetooth operates, and the frequency is 

also shared with 802.11. 900 MHz is used by Zigbee, which is an Internet of Things (IoT) 

communication technology. 5 GHz is shared with some radar systems, mainly on the 

upper channels of the frequency spectrum.

 168.  A.  The 802.11g wireless standard operates strictly on 2.4 GHz. The 802.11n wireless 

standard operates on both 2.4 GHz and 5 GHz. Both the 802.11a and 802.11ac wireless 

standards operate on 5 GHz.

 169.  B.  The hypervisor allows for multiple operating systems to share CPUs, RAM, network, 

and storage of a physical server. A physical server alone will not distribute resources  

over several operating systems. A virtual machine (VM) is what runs on top of the 

hypervisor. A virtual network is a resource that is shared on a hypervisor to the 

running virtual machines.

 170.  D.  A virtual machine, or VM, is an operating system that is running on hardware but is 

not directly attached to the hardware. It is decoupled from the hardware through the use 

of a hypervisor. The hypervisor creates an abstraction layer between the hardware and the 

operating system. An operating system that runs directly on hardware is not classified as 

a virtual machine since it monopolizes the hardware. An operating system that is running 

with dedicated hardware is not classified as a virtual machine because it has dedicated 

hardware. An operating system that is running on reduced hardware features is not 

classified as a virtual machine because it still runs directly on the hardware.

 171.  A.  The physical hardware (such as a server) used in virtualization is the host. The virtual 

machine (VM) runs on top of the hypervisor and allows for an operating system to 

be virtually installed. The hypervisor is installed on the host to allow multiple VMs to 

share the physical hardware. The guest is another name for virtual machines, since they 

are guests to the hardware via the hypervisor.

 172.  C.  A virtual switch connects the virtual machine NIC to the physical network. The 

virtual network interface card (vNIC) is the virtualized network card presented to the 

virtual machine. A trunk is a mode for a switchport or virtual switch that allows multiple 

VLANs to be tagged over a single virtual or physical link. NX-OS is a Cisco operating 

system that runs on the line of Nexus data center switches.

 173.  B.  A virtual firewall or virtual router is an example of a VNF. These devices are typically 

network functions that are found in internal networks such as firewalls and routers. 

These devices perform basic network functionality and run as virtual machines or virtual 

instances. A virtual switch is not considered a VNF because it is an elemental part of the 

hypervisor, used for communications. A database server and file server are not functions 

of a network; they are roles found on servers.

 174.  D.  If you wanted to scale a web server out to several other web servers, you would use 

Server Load Balancing as a Server (SLBaaS) from your cloud provider. Adding resources 

such as vCPUs and vRAM is an example of scaling a server up, not out. Adding DNS will 

not offset or accommodate the additional load on the web servers.

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