Ccna certification Practice Tests

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 69.  C.  Routing Information Protocol (RIP) has the lowest overhead of all of the routing 

protocols. However, it is not very scalable; the maximum number of hops is 15. BGP has 

tremendous overhead because of the storage and calculations on best path. OSPF has a 

large overhead as well because of storage and calculations to the shortest path. EIGRP is 

similar to OSPF in regard to storage and calculations for the next hop.

 70.  A.  The benefit of a dynamic routing protocol is that it creates resiliency when routes 

become unavailable. It does this by recalculating the best route in the network around 

the outage. When using dynamic routing protocols there is a higher RAM usage because 

of the route tables collected. CPU usage is also higher with dynamic routing protocols 

because of calculations. Bandwidth usage is also higher with dynamic routing protocols 

because of the traffic involved learning the various routes.

 71.  A.  The Routing Information Protocol version 1 (RIPv1) broadcasts updates for routing 

tables. OSPF exclusively uses multicast to send updates. EIGRP uses multicast to send 

updates as well and has a backup of direct unicast. BGP uses unicast to retrieve updates 

on network paths.

 72.  B.  Optimized route selection is a direct advantage of using dynamic routing protocols. A 

protocol such as OSPF uses the shortest path first algorithm for route selection. Routing 

tables will not be centralized since all routers participating in dynamic routing will 

contain their own routing tables. Dynamic routing is not easier to configure due to the 

upfront planning and configuration. A portion of the available bandwidth will also be 

consumed for the dynamic routing protocol.

 73.  A.  The Routing Information Protocol (RIP) is a distance-vector routing protocol that has 

a maximum of 15 hops. OSPF is an extremely scalable routing protocol, and therefore, 

OSPF isn’t limited to a hop count. EIGRP has a default hop count of 100 and can be 

configured for up to 255 hops. BGP is the routing protocol that routes the Internet; it 

does, however, have a maximum hop count of 255.

 74.  C.  The Enhanced Interior Gateway Routing Protocol (EIGRP) is a hybrid protocol. It 

has features of a vector-based protocol and a link-state protocol; hence it is considered a 

hybrid protocol. RIP is a distance-vector routing protocol that is used for small networks. 

OSPF is an extremely scalable link-state protocol. BGP is the routing protocol that is used 

to route packets on the Internet, and it is considered a path-vector protocol.

 75.  B.  Protocols such as RIP re-advertise routes learned. This can be problematic since it 

is the equivalent of gossiping about what they have heard. Routes learned through this 

method are never tracked for status or double-checked for validity. Distance-vector 

protocols do not keep a topology database; they just feed routes to the route table. 

Distance-vector protocols never check the routes they learn because of the method of 

routing through rumor.

 76.  B.  RIP, which is a distance-vector protocol, is best suited for networks containing fewer 

than 15 routers. This is because RIP is limited to a 15 hop count. Any route that is more 

than 15 hops away is considered unreachable. All other answers are incorrect and describe 

networks that are best suited for a hybrid, link-state, or path-vector protocol.

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