Ccna certification Practice Tests

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 68.  C.  You will need a virtual router running static NAT to translate the two different IP 

networks. This type of service is called a virtual network function, or VNF. A virtual 

switch is built into just about every virtualization platform, since layer 2 communications 

are normally required. A virtual firewall is a piece of software that allows you to protect 

your virtualization infrastructure, just like their hardware counterparts. Another IP 

scheme at the provider could help, but a router would still be required for connectivity.

 69.  C.  Network Time Protocol (NTP) is a standardized protocol for network time 

synchronization. Domain Name System (DNS) is a service that is used to translate a qualified 

domain name (FQDN) to an IP address. The rsync utility is a Linux/Unix utility used to 

synchronize (copy) a number of files to a remote system. A virtual private network (VPN) is a 

private encrypted tunnel that is normally created over a public Internet connection.

 70.  B.  You would use a crossover cable because a switch is a data communications equipment 

(DCE) Ethernet device. When connecting a DCE Ethernet device to another DCE Ethernet 

device, you would need to cross the connection with a crossover cable. Newer switches 

have medium dependent interface-crossover (MDI-X) capabilities to detect the need 

for a crossover cable and will automatically switch the cable over if a straight-through 

cable is used. A straight-through cable is used to connect a DCE Ethernet device such 

as a switch to data terminal equipment (DTE) such as a host. A rolled cable is used for 

serial communication between a router or switch and a modem or serial adapter for 

configuration. A shielded cable has either a metal webbed shield or foil shield to filter out 

electrical magnetic interference (EMI).

 71.  B.  Multi-mode fiber can be either 50 microns or 62.5 microns at its core. The maximum 

distance for a 50-micron fiber is 550 meters utilizing the 1000Base-LX specification. 

Unshielded twisted pair (UTP) is used in copper Ethernet cabling of hosts and network 

equipment. Single-mode fiber-optic cable is around 7 microns thick and is used for long-

distance communications. Shielded twisted pair (STP) is used in industrial settings when 

there is the potential for electrical magnetic interference (EMI).

 72.  C.  Although operation of computers connected to a switch uses a straight-through cable, 

management via the console port requires a rolled cable and an EIA/TIA 232 adapter. 

A straight-through cable is used to connect a data communications equipment (DCE) 

Ethernet device such as a switch to data terminal equipment (DTE) such as a host. You 

would use a crossover cable when connecting a DCE Ethernet device to another DCE 

Ethernet device; you would need to cross the connection with a crossover cable. Newer 

switches have medium dependent interface-crossover (MDI-X) capabilities to detect 

the need for a crossover cable and will automatically switch the cable over if a straight-

through cable is used. A shielded cable has either a metal webbed shield or foil shield to 

filter out electrical magnetic interference (EMI).

 73.  C.  10GBase-CX is commonly used in data centers. It is referred to by its nickname of 

Twinax. It is a fixed, balanced coaxial pair that can be run up to 25 meters. 10GBase-T 

is usually category 6 cable that is nominally run up to 55 meters in length to achieve 

10 Gb/s speeds. 40GBase-T is usually category 8 cable that is nominally run up to 30 

meters to provide 40 Gb/s speeds. 100GBase-TX is not a valid specification for Ethernet 

connectivity. 100Base-TX is standard 100 Mb/s connectivity that supports full-duplex 

communications.

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