Ccna certification Practice Tests

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Appendix 

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  Answers to Practice Test Questions

 43.  D.  The underlay is where you will set the maximum transmission unit (MTU). The 

overlay is where the tunnel or virtual circuit is built using the underlay as the transport. A 

Leaf switch is a part of the software-defined network (SDN), along with the Spine switch; 

both need to have the same MTU set.

 44.  D.  When you configure access control lists (ACLs) through any interface, you are 

affecting the control plane. This is because you are controlling the flow of data with 

the ACL. You are accessing the router through the management plane when you are 

connected to either the web interface or the command-line interface (CLI). The data plane 

is what you are controlling with the control plane. The data plane is the actual flow of 

information.

 45.  A.  Dynamic Multipoint Virtual Private Network (DMVPN) is a wide area network 

(WAN) technology that allows for virtual private networks (VPNs) to be created using the 

overlay of software-defined networking (SDN). Virtual Extensible LAN (VXLAN) is used 

to transport virtual local area network (VLAN) traffic over routed connections. Equal-

cost multi-path routing (ECMP) is used by Leaf and Spine switches to provide a next-hop 

packet forwarding decision.

 46.  C.  The Virtual Extensible LAN (VXLAN) protocol is used to create layer 2 tunnels over 

a layer 3 network. The VXLAN protocol functions by encapsulating layer 2 traffic inside 

of a layer 3 packet. The Equal Cost Load Balancing Protocol (ECMP) is used by Leaf and 

Spine switches to provide next-hop packet forwarding decisions. Dynamic Multipoint 

Virtual Private Network (DMVPN) is a point-to-multipoint VPN technology used for 

layer 3 connectivity over a wide area network (WAN) connection. The Enhanced Interior 

Gateway Routing Protocol (EIGRP) is a Cisco proprietary layer 3 routing protocol.

 47.  A.  The Simple Network Management Protocol (SNMP) is a protocol used on the 

management plane. SNMP is used for the management of routers and switches because 

it can be writeable and allow for configuration. The Cisco Discovery Protocol (CDP) is 

a control protocol because it communicates port properties via layer 2 frames, such as 

power requirements. The Internet Control Message Protocol (ICMP) is a control protocol, 

because it is used to send control messages back to the originating device. The VLAN 

Trunking Protocol (VTP) is used to communicate the control information of VLANs to 

other participating switches.

 48.  A.  The equal-cost multi-path routing (ECMP) packet forwarding protocol is used to 

calculate next-hop forwarding with SDN switching networks. The Open Shortest Path 

First (OSPF) protocol is a layer 3 routing protocol and not used with SDN switching 

networks. The Multiprotocol Label Switching Protocol (MPLS) is a protocol used with 

MPLS wide area network (WAN) providers and not used with SDN switching networks. 

The CLOS network is also known as a Leaf/Spine network, but it is the topology and not 

a next-hop packet forwarding protocol.

 49.  C.  The Cisco DNA Center is Cisco’s next-generation software-defined network (SDN) 

controller; it replaces Cisco’s Application Policy Infrastructure Controller - Enterprise 

Module (APIC-EM) platform. OpenFlow is a protocol used to configure software-defined 

networks. Cisco Prime Infrastructure (CPI) is a network management software suite, 

but it does not provide SDN functionality. Cisco Software Defined - Wide Area Network 

(SD-WAN) is an SDN controller for building WAN connections.

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Chapter 6: Automation and Programmability (Domain 6)