Ccna certification Practice Tests

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 40.  B.  Access layer switches connect to users and are edge network devices. The distribution 

layer connects other switches for redundancy. The core layer connects campuses together. 

Both the distribution layer and the core layer can connect the Internet to the network.

 41.  A.  Distribution layer switches connect to access layer switches and core switches to 

provide redundancy. Access layer switches connect to users and are edge network devices. 

The core layer connects campuses together. Both the distribution layer and the core layer 

can connect the Internet to the network.

 42.  C.  Core layer switches connect campuses together via the distribution layer switches. 

Distribution layer switches connect to access layer switches and core switches to provide 

redundancy. Access layer switches connect to users and are edge network devices. Both the 

distribution layer and the core layer can connect the Internet to the network.

 43.  B.  Based on the layout of your network, the three-tier model is the most appropriate 

model to design. Since there are four campuses, the core layer is recommended for 

connectivity between the campuses. The collapsed core model is best suited to a single 

campus. DoD model is a term used when referring to the layers of the OSI model in a 

macro model. Access model is not a term used with switching and routing design.

 44.  B.  The distribution layer is where redistribution of routing protocols should be performed. 

It should never be performed at the core or access layer. The core layer is where 

basic routing and switching is performed without slowing down any of the backbone 

communications. The access layer is where clients and end-user devices are supplied 

with network connectivity, allowing them to “access” the network. Routing layer is not 

terminology used to describe one of the three layers in the Cisco three-tier design model.

 45.  C.  The access layer is where collision domains should be created. This is called network 

segmentation. The core layer is where basic routing and switching is performed without 

slowing down any of the backbone communications. The distribution layer is where 

redistribution of routing protocols should be performed. Routing layer is not terminology 

used to describe one of the three layers in the Cisco three-tier design model.

 46.  B.  The distribution layer is a partial mesh topology. Links between the distribution 

switches and core switches are multi-homed to each device for redundancy. Also, the links 

between the distribution switches and access switches are multi-homed to each device 

for redundancy. Although this might seems to be a full mesh topology, the distribution 

switches are not connected to each other. A full mesh topology can often be found 

between the distribution and core layers. The core layer uses a star topology in a collapsed 

core design to connect lower layer switches. The ring topology is a legacy LAN topology 

and is often used in WAN communications.

 47.  A.  The E-Tree services of Metro Ethernet allow for a root to be established to serve 

the remote sites or leaf endpoints. The root can communicate to the leaf endpoints and 

the leaf endpoints can communicate to the root. However, the leaf endpoints cannot 

communicate with each other. Wireless WAN provides connectivity by using a star 

topology. E-Line and E-LAN services provide services in a point-to-point or point-to-

multipoint topology.

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